Pests and Diseases From Acer Gall Mites To Zucchini Yellow Mosiac Virus


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A
Common Name:- Acer Gall Mites
P_acerglmite Maple Bladdergall Mite (Vasates quadripedes).
There are many mites which causes galls on Maple(Acer species). These mites are not host specific and other trees are also attacked. The gall mites are microscpic and can only be seen under a mi...
Caused by:- Various Gall Mites
Control:- Light infestation can be controlled by picking off the individual l...

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Common Name:- Acorn Gall Wasp
P_acornglwsp The Acorn Gall wasp(Andricus quercuscalicis) causes Knopper Galls of Oak(Quercus) acorns. The wasp lays its egg on a developing acorn in early Summer. When the egg hatches the grub secretes chemicals which causes the acorn to develop into a gall. ...
Caused by:- The Wasp Andricus quercuscalicis
Control:- Unless the infection is great spraying is not necessary as most Oak...

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Common Name:- Adelgid
P_adelgids Adelgids are aphid-like insects in the family Adelgidae that primarily feeds on pines(Pinus), Spruce(Picea), Larch(Larix), DouglasFir(pseudotsuga menziesii) and Silver Fir(Abies). Adelgids feed by sucking their host plants sap. Infestations can ca...
Caused by:- Various Adelgid insects
Control:- Control measures depend on the kind of Adelgid and each type needs ...

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Common Name:- Alder Sucker
P_alderskr In Spring and Summer a fluffy white waxy substance covering a predominantly green, with dark markings aphids appears on the leaves and shoot tips of Alders. It is a sap-feeding insects 2-3 mm long. Nymphs have wide, flat bodies, large eyes and dar...
Caused by:- The Aphid Psylla alni
Control:- If necessary spray with an insecticide or wash them off with very s...

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Common Name:- Algae
P_algae1 Powdery green deposits on the leaves and trunk of plants, which can be wiped off leaving no discolouration. The plant growth is not impaired. In a forest the direction can be ascertain by looking at which side of the trunk the algae is on because ...
Caused by:- Single cellular plants
Control:- No control is necessary as the Algae is harmless. If it is unsightl...

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Common Name:- Alternaria Leaf Spot
P_alternaria Alternaria Leaf Spot is caused by several species of Alternaria fungus and attack many plants. Leaf spots vary in size from small dark circular spots up to 3 cm in diameter depending on the species and plant involved. They typically begin as small...
Caused by:- Several species of Alternaria fungus
Control:- Fungicidal applications applied as foliar sprays will control this ...

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Common Name:- American Gooseberry Mildew
P_amergoosemildew1 There are two mildew that affects gooseberries and related plants as well as Botritis fungi. One is the American(Sphaerotheca mors-uvae) and the other is the European(Microsphaera grossulariae). American Gooseberry Mildew is a much more vigorous f...
Caused by:- The Fungus Sphaerotheca mors-uvae
Control:- This fungus is encouraged by stagnant air around the branches and b...

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Common Name:- Anemone Rust
P_anemone1 The top of leaves become discoloured by yellow-orange spots found in mid-summer onwards. The underside of the leaf is covered with numerous brown/black markings. In extreme cases the whole plant will be affected and the leaves fall early. The fun...
Caused by:- The Fungus Tranzschelia pruni-spinosa
Control:- This disease is common and widespread. Consistent attacks may weake...

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Common Name:- Anemone Smut
P_anemonesmut There are many smut fungi that affect several plants including cereal crops like wheat. The main smut that affects Anemones is Urocystis anemones, but there are other smut fungi that can infect Anemones. The Smut spore masses develop beneath the s...
Caused by:- Mainly the Fungus Urocystis anemones
Control:- Remove and destroy, burn if possible, affected plants and leaves b...

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Common Name:- Anthranose
P_anthracnose Anthracnose is a term given to plant diseases caused by fungi in the genus Colletotrichum which attacks many plants from grass, vegetables, fruits, and trees. Symptoms include small, elliptical black abnormal injury, less than 5 mm in diameter tha...
Caused by:- Various Colletotrichum Fungi Species
Control:- The best way to prevent infection by anthracnose disease is approac...

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Common Name:- Antirrhinum Rust
P_antirrhinumrust1 There are several thousands species of rust, most are specific to a particular host and as with all rust the full life cycle requires an alternation between two unrelated plant hosts, but in the UK only the stages on antirrhinums usually occur. Th...
Caused by:- The Fungus Puccina antirrhini
Control:- Spray with any good fungicide especially those containing containi...

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Common Name:- Ants
P_ants Ants do not attack the plant as such but farm the aphids which suck sap from the plant and excrete sugary honeydew on which the ants feed. Ants often protect the aphids from attack. Several species of ants including the Yellow meadow ant, Lasius f...
Caused by:- Several species of ants
Control:- Nest can be treated with various dusts or there are jels which are ...

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Common Name:- Aphids
P_aphids1 This picture shows one of e winged aphid which will fly off to lay eggs on another plant.
Aphids suck the sap from leaves and stems and secrete honeydew which makes the leaves below sticky with honeydew which is the sugary sap of the plant....
Caused by:- Several species of aphids
Control:- As an emergency quick solution I squish them between the fingers or...

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Common Name:- Apple and pear Canker
P_nectriacanker2 Areas of the bark sinks inwards. It is most often associated with a wound or bud. The bark changes colour and shrinks and cracks forming concentric rings of bark which easily peels off. As the fungus grows around the stems the upper branches and l...
Caused by:- The Fungus Nectria galligena
Control:- This fungus spreads mainly by wind blowing the spores in spring. Th...

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Common Name:- Apple Bitter Pit
P_aplbtrpit Apple Bitter Pit is not a pest as such, but a physiological reaction to calcium deficiency. It often occurs when there is an irregular supply of water, which prevents calcium being taken up and circulated around the tree.
It may not be due ...
Caused by:- Calcium Deficiency
Control:- Some cultivars are more susceptible than others.<br /> Spraying wi...

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Common Name:- Apple Blossom Weevil
P_appbloswevil1 The apple flower buds start to develop but the petals fail to open and turn brown.If these buds are pulled apart a white larvae or pupa is found. These buds do not produce fruit. This weevil lays its egg in the unopened buds during mid to late ...
Caused by:- The Weevil Anthonomus pomorum
Control:- Usually it is only light infestation and the tree recovers well. If...

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Common Name:- Apple Capsid
P_appcapsid1 Ripe apples have of yellowish-brown corky bumps or scabby areas on the skin. Leaves at the shoot tips may be distorted with small holes. This bright green sap feeding insects approximately 7mm long injects toxic saliva into the plant as it feeds ...
Caused by:- The insect Plesiocoris rugicollis
Control:- Usually the infestation can be ignored as the damage is only skin d...

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Common Name:- Apple Leaf Miner
P_appleafminer1 Silvery white to brown tracks appear in the foliage of Prunus and Malus trees. These lavae of this small moth chews its way between the epidermis of the leaf. When they are pupating hammock like cocoons are attached to the bottom of the leaf.
Caused by:- The Larvae of the moth Lyonettia clerkella
Control:- Usually this pest attacks too late in the season to affect mature t...

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Common Name:- Apple Powdery Mildew
P_apppowmildew1 Powdery mildews are one of the most widespread plant diseases. They affect virtually all kinds of plants from cereals and grasses, to fruit trees, and broad-leaved shade trees.
With Apple Powdery Mildew, which also attacks Pears and other s...
Caused by:- The Fungus Podeosphaera leucotricha
Control:- Improve circulation by pruning and keep the tree growing healthily ...

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Common Name:- Apple Sawfly
P_appsawfly1 The young fruits fall in early to mid summer with a maggot hole in the side of the fruit. The hole is usually filled with excrement of the larvaeMature fruits may be misapprehended with a ribbon like scar from the bottom to the middle of the fruit...
Caused by:- The Sawfly Hoplocampa testudinea
Control:- Pick off and destroy fruits that are misshaped or show early damage...

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Common Name:- Apple Scab
P_appscab1 Apple scab is most prevalent in mild, damp seasons. It is caused by the fungus Ventura inaequalis which is closely related to the Pear scab fungus Venturia pirina. The fungus overwinters on fallen leaves in the form of spores, which can be splashe...
Caused by:- The Fungus Venturia inaequalis
Control:- Good husbandry is essential in preventing this disease. Therefore r...

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Common Name:- Apple Sooty Blotch
P_appsootblotch1 Sooty greenish-black spots develop on fruit skin of apples and plums. The blotches do not enter the fruit and can be scraped off and the fruit development is not affected. This fungus overwinters on the stems and is common on trees growing in shad...
Caused by:- The Fungus Gloeodes pomigena
Control:- It is rarely necessary to control this fungus, but a winter tar was...

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Common Name:- Apple Sucker
P_appsucker1 Flattened pale green insects, up to 2mm long, infests the blossom trusses in the spring. They kill the flowers and prevent fruit setting. These sap feeding insects overwinter as eggs and hatch at leaf break in the spring. The adult stages resemble...
Caused by:- The insect Psylla mali
Control:- A winter tar wash and spraying, at the bud stage of the flowers, wi...

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Common Name:- Apple Water Core
P_aplewtrcore The exact cause of Apple Water Core is not known for sure, but it is not a pest problem as such, but a physiological problem caused by growing conditions. It is especially a problem where the weather is very hot followed by rain and cold nights ar...
Caused by:- Physicological Causes
Control:- Planting apple trees on well-drained sites with irrigating during p...

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Common Name:- Aquilegia Sawfly
P_aquilsawfly1 Caterpillar larvae approximately 18mm long eat the leaf margins if Aquilegias. They are pale green. and several generations are produced in one year. Only the leaf stalk and flower stems are left, which leave the plant weakened. They lay their egg...
Caused by:- The Sawfly Pristiphora aquilegiae
Control:- Spraying with a suitable insecticide unless you can pick them off a...

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Common Name:- Asparagus Beetle
P_asparabeetle1 Asparagus plants loose their leaves as the larvae and adults feed on the leaves and outer bark of stems. The shoots above the bark damage slowly dies. The adult beetle is black with six yellow markings on their wing cases and have a reddish thorax...
Caused by:- The Beetle Crioceris asparagi
Control:- Removal of the beetle if seen and spraying with a suitable insectic...

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Common Name:- Aster Wilt
P_asterwilt1 There are many pathovar of Fusarium many of which attack specific plants, bulbs, fruits and leaves. With aster the plants wilt and fall over. The base of the stems are blackened and sunk inwards a furry whitish-pink fungal growth often occurs on t...
Caused by:- The Fungus Fusariom oxysporum
Control:- Remove and dispose of affected plants and soil around the plants. I...

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Common Name:- Azalea Bark Scale
P_azaleabarkscale Azalea Bark Scale Acanthococcus azaleae (Eriococcus azaleae) which belongs to the family Eriococcidae prefers azalea or rhododendron but can infest hawthorn, andromeda, maple, willow, poplar, willow and ornamental cherry trees and other plants. F...
Caused by:- The Scale insect Acanthococcus azaleae
Control:- There are biological predators that can be used to control this pes...

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Common Name:- Azalea Cottony Scale
P_azaleacottscale Azalea Cottony Scale can infest holly, yew, euonymus, maple, and other plants. Females are approximately 1/8-inch long with white felt-like sacs that are secreted in April/May which is where the eggs are laid in the spring and hatch from June to J...
Caused by:- The Scale Insect Pulvinaria floccifera
Control:- A wash with oily insecticides or a soap wash will kill pests and eg...

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Common Name:- Azalea Gall
P_azaleagall1 Azalea is caused by the fungus Exobasidium vaccinii. Pale green growths appear instead of leaves, petals, branch tips and seed pods on azaleas and Rhododendrums. Sometimes they are pinkish-red. The galls later turn powdery white as spores develop ...
Caused by:- The Fungus Exobasidium vaccinii
Control:- Remove galls before spores form and spray with a suitable insectici...

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Common Name:- Azalea Whitefly
P_azaleawhitefly1 Small white spots and small white flies on the underside of leaves is an indication of infestation of Azalea Whitefly (Pealius azaleae.) The white winged insects live on the underside of the leaves of azaleas. They suck the sap and extrude honeyde...
Caused by:- The insect Pealius azaleae
Control:- Spray with a suitable insecticide especially when the adults are pr...

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B
Common Name:- Bacteria
P_bacteria1 There are many different types of bacteria that affects plants or parts of plants. Leaves can become spotted with a yellowish halo around the affected spot or softer parts like tubers and roots may discolour and rot often becoming slimy and smelly...
Caused by:- Several Bacterial species
Control:- Usually bacteria enter plants by damage areas and usually only affe...

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Common Name:- Bacteria Wetwood
P_slimeflux Bacterial Wetwood is a bacterial disease called Slime Flux which attacks many trees such as apple, ash, aspen, beech, birch, cottonwood, elm, fir, hickory, maple, mulberry, oak, plum, ...
Caused by:- Various Bacteria, Fungi and Yeast
Control:- It can be difficult to prevent the stem damage that leads to the de...

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Common Name:- Bacterial Canker
P_bacterialcanker1 Areas of bark may flatten and sink inwards. The damage areas may ooze resin. Affected branches may not open buds or if they do they wither and die soon after opening. leaves may not develop properly due to lack of nutrients and may yellow prematur...
Caused by:- The Fungi Pseudomonas prunorum or syringae
Control:- Prune out damaged areas and spray with copper based fungicide like ...

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Common Name:- Bacterial Soft Rot
P_bacterialrot The bacteria Streptomyces ipomoeae on sweet potatoes.
Bacterial Soft Rot is also called Soft Rot Tubers, root and fruit are usually affected although on some plants stems are ...
Caused by:- Various Bacteria
Control:- Prune out affected areas as early as possible. Sterilize equipment ...

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Common Name:- Balsam Wooly Adelgid
P_blsmwlyadel Balsam Woolly Adelgids is known as the Silver Fir Adelgid, Adelges piceae and is a is a tiny, non-flying, sap sucking insect that attacks mainly Abies species of trees.
They are...
Caused by:- The Adelgid Adelges piceae
Control:- Spraying with insecticides is effective, but costly and is difficul...

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Common Name:- Bark Beatles
P_barkbeetles There are several beetles that eat the tree below the bark. Some carry diseases from one plant to the next. One of the most famous is Scolytus scolytus The elm Bark beetle. Many beetles eat channels below the bark where the xylem and phloem cells ...
Caused by:- Various Beatles
Control:- The best control is by pruning out and burning affected branches an...

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Common Name:- Bay Sucker
P_baysucker The edges of the leaves of the bay tree becomes thickened and curled over. Later the yellowish leaf edges becomes a reddish brown. It is caused by Trioza insect sucking the sap from the tree leaves which curves to protect the insect.
Caused by:- The Insect Trioza alacris
Control:- I find that it does not cause worrying infestations and pick off th...

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Common Name:- Bean Anthracnose
P_beananthracnose Seedlings grown from infected seeds often have dark brown to black sunken lesions on the cotyledons and stems Severely infected cotyledons die early, and growth of the plants is stunted. Diseased areas may girdle the stem and kill young plants. ...
Caused by:- The Fungus Colletotrichum lindemuthianum
Control:- Use certified seeds and bury plant remains. Rotation of crops will ...

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Common Name:- Bean Blight
P_beanblight Known as Common Blight the characteristic leaf symptoms consist of irregular areas of brown dry tissues surrounded by a narrow lemon yellow border. These lesions frequently occur at the leaf margins. Pods have sunken circular spots, at first water...
Caused by:- Xanthomonas phaseoli
Control:- Use certified seeds as the infection can be carried by the seeds. P...

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Common Name:- Bean Choclate Spot
P_beanchoclatespot Brown spots appear on the leaves of broad beans. Streaks may also appear on the stems, pods and flowers. Severely affected plants may die or at least yields will be reduced. Damp and wet conditions help the spread.
See these other Grey Moul...
Caused by:- The Fungus Botrytis fabae
Control:- Allow free air circulation as much as possible and grow on well dra...

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Common Name:- Bean Halo Blight
P_beanhaloblight Small spots appear on the leaves of French or Runner Beans. The spots appear at first jelly filled turning darker. Each spot is surrounded by a yellow halo. Later the leaves become chlorotic then die. The stems and pods can also be affected. Initi...
Caused by:- The Bacteria Pseudomonas phaseolica
Control:- Pick off infected leaves as soon as they appear and burn them. Some...

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Common Name:- Bean Rust
P_beanrust Rust on Phaseolus Genus of beans which include beans Bush bean, French bean, Kidney bean, Pinto bean, Pole bean, Runner bean, Snap bean is caused by the fungus Uromyces appendiculatus. This fungus is unrelated to Broad Bean rust which is caused by...
Caused by:- The Fungus Uromyces appendiculatus
Control:- As with any fungal disease one of the best ways of preventing it is...

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Common Name:- Bean Seed Beetles
P_beanseedbtle Although there are several beetles that attack bean seeds Broad beans are usually attacked by the beetle Bruchus rufimanus which lays eggs inside the bean pods and enter the seeds then emerge before the seeds are planted ready to infect the next y...
Caused by:- The Beetle Bruchus rufimanus
Control:- Very little can be done apart from spraying with a systematic insec...

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Common Name:- Bean Seed Fly
P_beanseedfly The germinating seeds of French and Runner beans are eaten by white fly larvae which are living in the soil. The seedlings are usually killed, but those that survive are often ragged or have multiple shoots as the growing tips are damaged.
Caused by:- The Maggot of Delta platura
Control:- Treating the seeds with Lindane dust or similar insecticides. Sowin...

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Common Name:- Beech Bark Desease
P_beechbarkdis Areas of the bark die and appear slightly sunken. These areas often extrude a tar like substance. The tree loses vigour and the leaves turn yellow. Tiny red fungal growths appear on the damaged bark. This disease often accompanies Beech Bark Scal...
Caused by:- The Fungus Nectria coccinea
Control:- As this disease enters via wounds it is best to protect any damaged...

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Common Name:- Beech Bark Scale
P_beechbarkscale A powdery white waxy covering appears in the crevices of the bark of beech trees, under which small sap feeding scale insects live. The trees are rarely killed by this, but it allows the Beech Bark disease to enter the wound and this then eventual...
Caused by:- The Scale Insect Cryptocococcus fagisuga
Control:- Spray with a winter tar wash or inecticidal or horticultural oil. W...

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Common Name:- Beech Gall Midge
P_beechgallmidge In Summer yellowish-brown tubular growths are seen on the upper parts of the leaves of Beech. These contain the larvae of the fly which lay their eggs on the leaves in mid-summer. There are other flies that cause this effect.
See also these...
Caused by:- The Insect Hartigiola annulipes
Control:- Spraying with a systemic insecticide if possible. The flies rarely ...

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Common Name:- Beech Leaf Mining Weevil
P_beechleafmin,jpg?1280881815 The leaves of Beech are eaten leaving round holes. They lay their eggs in the center of the leaf and the larvae mines its way to the tip of the leaf leaving straight tracks of dead leaf, which often merge to kill part of the leaf.
See these...
Caused by:- The Beetle Rhynchaenus fagi(Orchestes fagi)
Control:- As this usually happens in the spring clipping the Beech and destro...

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Common Name:- Beech Wooly Aphid
P_beechwoolyaphid Small yellow insects with a white waxy covering infests the young shoots of Beech in spring and summer. They often look like whiteflies. They suck the sap of the tree and weaken it. Their sugary secretions causes other moulds to develop on the lea...
Caused by:- The Aphid Phyllaphis fagi
Control:- Spray with insecticide if possible preferable systematic.

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Common Name:- Beefstake Fungus
P_beefstakefungus This fungus only seems to grow on mature trees that are several decades old. In England it is mainly seen on Oaks and Sweet Chestnuts in autumn, but other trees in other countries are affected. The fungus looks and taste a bit like beef. It bleeds...
Caused by:- The Fungus Fistulina hepatica
Control:- Apart from removing the fruiting brackets to limit the spread there...

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Common Name:- Bees
P_bees1 There are many types of bees that can cause problems in the garden. By far the most noticeable one is the Leaf Cutter Bees usually cause damage to leaves, but is seldom enough to worry about unless showing plants for exhibition. Most bees can be i...
Caused by:- A Few species of Bees
Control:- Call a beekeeper out to remove bumblebees if you cannot leave them ...

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Common Name:- Beet Leaf Miner
P_beetleafminer This picture was obtained from Wiki Commons and shows the adult fly Pegomya hyoscyami. The beet leaf-miner Pegomya hyoscyami is the same larvae as one of the spinach leafminer. It is a small anthomyiid fly whose larvae attack the leaves of spinac...
Caused by:- The Larvae of Pegomya hyoscyami
Control:- If the infestation is not large it is possible to remove the affect...

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Common Name:- Begonia powdery mildew
P_begoniapomild Powdery mildews are one of the most widespread plant diseases. They affect virtually all kinds of plants from cereals and grasses, to fruit trees, and broad-leaved shade trees.
Powdery mildews are usually host specific, which means they do ...
Caused by:- The Fungus Microsphaera
Control:- This fungus is accelerated by dry roots and damp leaves with poor a...

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Common Name:- Big Bud Mites
P_bigbudmites There are several trees, shrubs and climbers that are affected by different species of mites. The buds usually develop over the winter and can usually be seen easier as usually the leaves are absent. A microscope is usually needed to see the mites...
Caused by:- Several Gall Mites
Control:- On some species of plants they can be tolerated, but sometimes spra...

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Common Name:- Birch Witches Broom
P_birchwitchbroom Branched twigs which looks like a broom or birds nest. The leaves turn yellow and are covered with fungal spores.
Caused by:- The Fungus Tapbrina betulina
Control:- The broom like growths are susceptible to a heavy frost, but are be...

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Common Name:- Black Bean Aphid
P_blackbeanaphid The aphids attack the new tips of several plants, but spring sown Broad beans are particularly affected. The sap feeding aphids weaken the plant and reduce yields.
Caused by:- The Aphid Aphis fabae
Control:- Spray with a propriety insecticide as soon as seen. Removal of seve...

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Common Name:- Black Root Rot
P_blkrtrot Black root rot (BRR) is a common and destructive fungal disease caused by the fungus Thielaviopsis basicola which attacks a variety of greenhouse bedding and pot crops. It begins by attacking the middle of the root and forms small, black cankers t...
Caused by:- The Fungus Thielaviopsis basicola
Control:- Good husbandry is probably the best defence for avoiding this disea...

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Common Name:- Black Spot
P_blacksopt3 Rose black spot is specific to roses and all types are susceptible. It is caused by the fungus Diplocarpon rosae which kills the cells on the leaves of roses leaving brown to black spots on leaves. The spots may join together or remain separate.
Caused by:- The Fungus Diplocarpon rosae
Control:- Rake up and destroy fallen leaves in the autumn. Prune out all stem...

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Common Name:- Blackberry Cane Spot
P_bberrycsnespot Whitish-grey round shaped spots surounded with a purple margin appear on the canes. Small black fungal fruiting bodies appear in the center of the spots. The canes then die back.
Caused by:- The Fungus Elsinoe veneta
Control:- Cut out infected canes and spray with a propriety fungicide.

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Common Name:- Blackcurrant Gall Midge
P_bcurrantgallmidge Leaves of the Blackcurrant does not develop and remain small due to the larvae of Dasineura tetensi feeding on the shoot tips. The leaves and or tips often dry up and die.
See also these other Galls
Caused by:- The Insect Dasineura tetensi
Control:- Spraying with a propriety insecticide before the buds open in spring.

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Common Name:- Blackfly
P_blackfly There are many different species of blackflies, some of which attack specific plants. They all suck the sap from the plant they infest and weaken it.
They appear black compared with the common aphid which is green, but the effects are the s...
Caused by:- Several species of Aphids
Control:- As an emergency quick solution I squish them between the fingers or...

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Common Name:- Bleeding Canker
P_bleedingcanker A light brown substance ouze from the bark of mature trees. Patches of the bark may die and crack, which will allow other bacteria to enter and further affect the tree. Branches may die if the fungus totally ring the bark. Picture by Joseph O'Brie...
Caused by:- Fungus of the Phytophthora species
Control:- Cut out damage areas and protect with a pruning paint. A winter tar...

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Common Name:- Bloossom End Rot
P_blosssomrot Patches of the fruit at the end where the blossom was attached appear brown and leathery. Some of the fruit will rot and some fruit on the same bunch will appear healthy.
Caused by:- Dry Acidic soil
Control:- Some plants like Citrus and Rhododendron needs acidic soil, but mos...

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Common Name:- Blossom Wilt
P_blossomwilt Blossom Wilt is a fungal disease, which also affects apples, pears, plums, cherries and related ornamentals. It kills blossoms, spurs and small branches. The problem is caused by two Sclerotinia species of fungi S. laxa (Monilinia cinerea) and S. ...
Caused by:- The Fungus Sclerotinia
Control:- Spraying operations can only be effective when they kill the spores...

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Common Name:- Bluebell Rust
P_bluebellrust Dark brown fungal pustules appear on the leaves. These may be round or elliptical. Flower or leaves are also attacked. The leaves yellow and die. It weakens the bulbs and limit flowering the following year.
See also these other rusts
Caused by:- The Fungus Uromyces muscari
Control:- As with any fungal disease one of the best ways of preventing it is...

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Common Name:- Bolting
P_bolting Several plants, like onions, Cauliflower and cabbages, may send up flower spikes before it has properly matured. It is caused by many growing conditions, such as dryness, coldness, inappropriate use of fertilizers, loose or solid soils and other g...
Caused by:- Growing conditions
Control:- Choose the right varieties for the conditions or make the condition...

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Common Name:- Boron Deficiency
P_borondiff The symptoms vary with the plants or tree affected. On root vegetables the growth is inhibited and cracking of the root which leads to rotting. On trees the leaves may be distorted and smaller than usual. Heavy rainfall areas are prone to this def...
Caused by:- Excess Soil Lime
Control:- Applying Borax in quantities depending on rainfall as Boron is rapi...

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Common Name:- Botrytis
P_rosebotysis Botrytis cinerea(Botryotinia fuckeliana) has a very wide host range and produces white to gray to brown fungal growth on infected areas. The affected area eventually turns black and can resemble blackspot on roses.
It is usually always pres...
Caused by:- The Fungus Botritis cineria
Control:- Controlling this fungus is often difficult as it is so widespread s...

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Common Name:- Box Succker
P_boxsucker The young shoots are stunted closely spaced and cupped. The shoots looks like miniature cabbages. A whitish liquid can be emptied from the cupped leaves in spring which is the excrement of the sap feeding insects. The sap feeding nymps are pale g...
Caused by:- The Insect Psylla buxi
Control:- Spraying in spring with an insecticide. Clipped box may not get aff...

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Common Name:- Bracket Fungus
P_bracketfungus1 Bracket fungi may appear on many different tree species. Some fungi species have a wide host range. Others are characteristic on certain trees e.g. Meripilus giganteus on beech, Daedaleopsis confragosa on deciduous trees like Alders, Birches, and ...
Caused by:- Several Fungus
Control:- Avoid damage to the bark, which acts like skin in animals. Healthy ...

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Common Name:- Brassica Dark Leaf Spot
P_brasicadklfspt Several round brown spots develop on leaves each having concentric rings of small fungal growth bodies. Eventually holes may develop or the leaf dies.
Caused by:- The Fungus Alternaria brassicola
Control:- Wet and poor circulation of air helps the spread of the fungus. Too...

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Common Name:- Brassica Downy Mildew
P_brassicadnymldw Downy mildews are a common plant disease. They affect virtually all kinds of plants.
Brassicas Downy mildew is a disease of seedlings and also mature plants. It is caused by a fungus Peronospora parasitica which penetrates the tissues under...
Caused by:- The Fungus Peronospor parisitica
Control:- The best method of control is prevention therefore good hygiene and...

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Common Name:- Brassica Light Leaf Spot
P_brassicalilfspot Brassica Light Leaf Spot is caused by the fungus Cylindrosporium concentricum(Pyrenopeziza brassicae) which is a serious pest of Oil Seed Rape. The symptoms appear from late autumn as light green areas on leaves surrounded by a halo of white/pink ...
Caused by:- The Fungus Cylindrosporium concentricum
Control:- Remove infected leaves ASAP and burn to avoid spreading the fungus....

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Common Name:- Brassica Ring Spot
P_brassicaringspot Brown concentric spots with yellow edges occur on the leaves. Later black fungal spore bearing bodies are visible on the spots.
Caused by:- The Fungus Mycosphaerella brassicola
Control:- Remove and burn infected leaves ASAP.

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Common Name:- Brassica Soft Rot
P_brassicasoftrot Soft Rot caused by Paul Bachi, University of Kentucky Research and Education Center, Bugwood.org. The rot usually starts with damage to the plant by slugs, snails and other boring insects. When seen it is usually too late to save the plant. Too we...
Caused by:- Several Bacteria
Control:- Dig up and burn infected plants to contain spread. Avoid damage to ...

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Common Name:- Brassica White Blister
P_brassicawteblstr Brassica White Blister is caused by the fungus Albugo candida which related to the downy mildews. Like Downy Mildew it feeds of the plant tissues and causes white pustules to appear on the leaves which distorts them. Brassica White Blister often o...
Caused by:- The Fungus Albugo candida
Control:- Practice good hygiene and pick off and destroy affected leaves and ...

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Common Name:- Brassica Wirestem
P_brassicawirestem The fungus mainly attacks cauliflowers and but other vegetable plants such as cabbage, lettuce and brussels sprouts are also affected. Damage caused by wirestem . Wirestem normally attacks seedlings and causes the stems to fail and the seedling t...
Caused by:- The Fungus Thanatephorus cucumeris
Control:- Good soil hygiene is essential for seedlings. Reduce the acidity...

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Common Name:- Broad Bean Rust
P_brdbeanrst Broad Bean rust which is caused by the fungus Uromyces viciae-fabae and infects Vicia beans which include Bell Bean or Tic Bean, Broad Bean, Fava Bean, Field Bean. This fungus is unrelated to rust on the Phaseolus Genus of beans which include bean...
Caused by:- The Fungus Uromyces viciae-fabae
Control:- As with any fungal disease one of the best ways of preventing it is...

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Common Name:- Broom Gall Mite
P_broomgallmite During Spring and summer the buds on Broom (Cytisus) do not open and develop into a mass of growth covered with silvery hairs. When they dry up they remain on the plant over winter. A microscopic Gall mite lives in the unopened buds. In severe cas...
Caused by:- The Insect Eriophyes genistae
Control:- Pruning out the infected buds is the main form of attacking the mit...

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Common Name:- Brown Rot
P_brownrot1 Brown areas appear on fruit then white postules appear in brown areas.
Caused by:- The Fungi Sclerotinia fructigena and S. laxa
Control:- remove affected fruit and spray with fungicide.

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Common Name:- Brown Scale
P_brownscale Brown scale insects up to 5mm long attach themselves to the stems and leaves of several plants and shrubs, especially in sheltered growing areas. The sap feeding insects excrete honeydew which makes the leaves sticky and allow other moulds and fun...
Caused by:- The Scale Insect Parthenolecanium corni
Control:- The shell or scale protects the older insects from insecticides, so...

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Common Name:- Brown Tail Moth
P_brntlmoth The Brown Tail Moth (Euproctis chrysorrhoea) is a beautiful white moth with a brown tail. The caterpillars are brown, has a dotted white line down each side of their bodies which are covered in hairs and two very distinctive red dots on the top re...
Caused by:- The Larvae of the Euproctis chrysorrhoea Moth
Control:- The best way to control this moth is to cut out the nests in the wi...

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Common Name:- Bub Drop
P_buddrop1 There are many causes why plants drop their buds. These can range from missing nutrients, improper humidity, light levels or temperature, lack of water or overwatering., plants being pot-bound, root deseases, using the wrong insecticide, using ins...
Caused by:- Various Stresses
Control:- Growing plants according to their requirements, which involves a st...

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C
Common Name:- Cabbage Moth
P_cabbagemoth1 The Cabbage Moth (Mamestra brassicae) is a common European moth, becoming less the further north you go. As the name suggests the larvae, which is green or brown with dark spots, mainly feeds on cabbage (Brassica spp.), but does attack other plant...
Caused by:- The Moth Mamestra brassicae
Control:- The best way to prevent worms is to stop the coddling moths from la...

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Common Name:- Cabbage Root Fly
P_cabbagerootfly1 The Cabbage Root fly Delia radicum, is also known as the cabbage fly, root fly or turnip fly, is a pest Brassica crops such as Brussels sprouts, Kale, Swedes and Turnips. The larvae are known as the cabbage maggot or root maggot. The adult flies a...
Caused by:- The Insect Delia radicum
Control:- Dust planting hole with an insecticide like Lindane or Primiphos-Me...

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Common Name:- Cabbage White Butterflies
P_cabbagewhitebut1 There are two types of Cabbage White Butterflies the large and the small. The Large Cabbage White Butterfly is less widely distributed in the world than the Small. The caterpillars will be found on Brassicas eg. cabbage, swede, kale, throughout th...
Caused by:- TheButterflies Pieris brassica & p. rupae
Control:- Vigilance in inspecting the Brassica on the underside of the leaves...

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Common Name:- Cabbage Whitefly
P_cabbwhitefly The whitefly lays their eggs on the underside of Brassica leaves in their hundreds. Often they are not noticed until the flies are hatched and are disturbed by the brushing past of the plants. The Brassicas are covered on the underside of their le...
Caused by:- The insect Aleyrodes proletella
Control:- The adults are active throughout the year and do attack other plant...

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Common Name:- Calcium Deficiency
P_calciumdef Although this is not a pest as such it often causes problems related to certain pests. The effects on a plant is different according to the plant and cause. On Brassicas the browning of internal leaves, stunting and browning of central leaves of C...
Caused by:- Various Causes
Control:- Liming the soil to raise the ph of the soil especially where Brassi...

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Common Name:- Camellia Gall
P_camelliagall Camellia gall is caused by the fungus Exobasidium camelliae. The galls are formed at the shoot tips where the leaves should be in early summer. This disease only attacks camellias especially in wet weather. A similar disease of azaleas and rhodod...
Caused by:- The Fungus Exobasidium camelliae
Control:- The gall is more prevalent in wet conditions and the spores are dis...

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Common Name:- Camellia Yellow Mottle
P_cameliayelmot The mottling of the leaves of Camellia with yellow to white markings. It may also cause discoloured areas within the petals (flower breaking).
Caused by:- A Virus
Control:- Camellia yellow mottle virus is a virus of camellias. It does not a...

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Common Name:- Canker
P_nectriacanker2 Cankers are dead sections of bark on branches or main trunks of trees. Bark may be killed by mechanical damage or by plant pathogens, especially fungi and bacteria. Most plant pathogens are unable to penetrate bark directly but will quickly coloni...
Caused by:- Various fungii
Control:- Prune out the affected branch as early as possible. Treat with fung...

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Common Name:- Capsid Bugs
P_capsidbug The shoots of several plants are mishapened with many small holes. Several plants shoots open unevenly or abort at an early stage in its development. Lygocoris is pale green and are about 5mm long as an adult and suck the sap from the shoots and ...
Caused by:- The Insect Lygocoris pabulinus
Control:- The only solution is to spray with an insecticide, preferable with ...

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Common Name:- Carnation Tortrix Moth
P_carntortmoth The Carnation Tortrix Moth, Cacoecimorpha pronubana feeds on several other plants, but it can be a serious insect of carnation both indoor and outdoor. Its distribution is now worldwide.
The adult moth is usually seen during the evening fli...
Caused by:- The Moth Cacoecimorpha pronubana
Control:- The caterpillar usually has at least two generations per year, betw...

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Common Name:- Carrot Cavity Spot
P_carrotcavspot Round to elliptical to irregularly shaped discolouration develop on the roots which can crack and develop secondary infections of various bacteria which eventually destroys the plant and roots.
Caused by:- Unknown Causes
Control:- Although fungus is suspected this is not proven and some people sus...

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Common Name:- Carrot Motley Dwarf Virus
P_carotmotdwfvir Carrots and Parsley plants infected at the seed stage will be stunted, and yellow to red in color. Plants appear as if they are suffering a nutritional deficiency. When plants are infected at later stages of growth, plants may or may not have stun...
Caused by:- Virus
Control:- Carrot motley dwarf virus symptoms are caused by the infection of c...

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Common Name:- Carrot Red leaf Virus
P_carotredleafvir In carrot the virus causes reddening and yellowing of leaves and some stunting of the plants. It usually occurs in association with carrot mottle virus to cause the disease known as motley dwarf, in which the reddening, yellowing and stunting is ...
Caused by:- Virus
Control:- The virus can have several hosts and is spread by aphids. Some cult...

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Common Name:- Carrot Root Fly
P_carrotrootfly The roots of the carrots and related species are bored by a slim creamy-yellow maggots up to about 1cm long.As the tunneled parts die this leaves a brown stain usually on the surface of the root crop. This attack can lead to secondary attack by fu...
Caused by:- The Insect Psila rosae
Control:- The larvae of the carrot fly has two or three generations per year ...

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Common Name:- Caterpillars
P_caterpillars Caterpillars are the larval stage if insects mainly Moths and Butterflies, but there are several flies and beetles which have larval stages which attack plants in many ways. Mainly by eating the leaves, fruits, roots and seeds.
Caused by:- Various insects
Control:- most caterpillars can be eradicated by using biological means like ...

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Common Name:- Cats
P_cats Cats of the domestic type (Felis catus)can reek havoc in a garden or vegetable bed. Their urine can scorch the leaves and bark of plants, Mature trees and shrubs can be killed by cats using the trunk as a scratching post, many cats poo on the lawn...
Caused by:- The Animals Felis catus
Control:- There are many remedies which help to prevent cats being a nuisance...

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Common Name:- Cavity Rot
P_cavityrot Once the bark of trees are damaged various fungi can attack the exposed wood leading to rot and decay which can lead to a cavity forming. This will weaken the trunk and branches which can then become dangerous to passers-by.
Caused by:- Various Fungii
Control:- Trees usually form callouses over damaged wood as well as producing...

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Common Name:- Cedar Aphid
P_cedar aphid Cedar aphid (Cedrobium lapportei), which originates from Morocco, is a small aphid about 1.5-2mm long and greyish-brown with a paler stripe starting from the head end. They suck the sap from the tree and weaken it. It infests cedars at the bases ...
Caused by:- The Aphid Cedrobium lapportei
Control:- If the tree is small it can be sprayed with an insecticide. Hosing ...

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Common Name:- Cedar Leaf Blight
P_cdrlfblight Didymascella thujina is an ascomycete fungi from the family of Hemiphacidiaceae, which causes Cedar leaf blight (or Keithia Thujina needle blight disease, after the original genus name) in several cedar(Thuja) species. The disease is indigenous to...
Caused by:- The Fungus Didymascella thujina(Keithia thujina)
Control:- Control of the disease can be effective with certain fungicides and...

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Common Name:- Cedar Leaf Miners
P_cedarlfminer Cedar leaf miners are insects, whose larvae eat the inside of the leaves of cedar trees beginning at the tips of the outer most branches. This causes the leaves to wither and turn a translucent brown. The trees usually survive, but they can die if...
Caused by:- Several Genera of leaf miner insects
Control:- Except in heavy infestations, this problem can be controlled by pru...

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Common Name:- Cedar Quince Rust
P_qncerust Gymnosporangium clavipes with aecia spore producing bodies on a Hawthorn(Crataegus) branch.
Cedar Quince Rust is caused by the fungus Gymnosporangium clavipes and like most rust diseases needs two hosts to complete its life cycle. This rust...
Caused by:- The Fungus Gymnosporangium clavipes
Control:- Monitoring rust canker on red cedar trees and temperatures during w...

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Common Name:- Celerey Leaf Miner
P_celerylfminer The leaves of Celery and related plants are eaten from between the epidermis by the larvae of a fruit fly. This leave the leaves looking as they are scorched. The maggots are up to about 6mm long and live inside the leaves until they pupate into a...
Caused by:- The Insect Euleia beraclei
Control:- They are more than generation per year of Euleia beraclei and plant...

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Common Name:- Celery Leaf Spot
P_celeryleafspot This fungus causes circular to irregular in shape spots on Celery or Celeriac leaves. These range in sizes from 3 to 10 mm in diameter. Dark coloured fruiting bodies of the fungus which form in the center of leaf spots give the spots a grainy appe...
Caused by:- The Fungus Septoria apitcola
Control:- This fungus can be spread by the spores overwintering on the seeds ...

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Common Name:- Centipedes
P_centipedes There are many hundreds of Centipedes which are arthropods belonging to the class Chilopoda. Adult centipedes are yellowish to dark brown, often with dark markings, and 1/8 to 6-inches long. The body is flattened with 15 to 177 body segments, wh...
Caused by:- Several arthropods of the Class Chilopoda
Control:- Centipedes seldom need to be controlled unless they become a nuisan...

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Common Name:- Chafer Grubs
P_chafergrubs There are several beetles the larvae of which are known as Chafer Grubs The Grubs are found in the soil and are usually curled up in the shape of a letter C and having three pairs of legs near the head which is usually shiny. They chew through the...
Caused by:- Larvae of various beetles
Control:- The adult beetles emerge from the soil around May. Using a biologic...

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Common Name:- Cherry and Pear Slugworm
P_pandcslugworm The Pear and Cherry Slugworm (Caliroa cerasi) attacks Hawthorne, mountain Ash, Plums, Sorbus and Quince. It is actually a bottle green insect larvae, of a sawfly, which covers its body in a black slimy mucilage which makes it look like a slimy sl...
Caused by:- The Sawfly larvae of Caliroa cerasi
Control:- Spray with a contact insecticidal spray such as soon as they are no...

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Common Name:- Cherry Blackfly
P_cherryblackfly During late spring and early summer, the undersides of the leaves and the shoot tips are covered with shiny black aphids which suck the sap from the tree and leaves. The leaves then becomes curled up and misshapen. By the time the leaves are curle...
Caused by:- The Aphid Myzus cerasi
Control:- These aphids hatch from eggs laid on the tree in the late Autumn an...

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Common Name:- China Mark Moth
P_chinamarkmoth The caterpillars can affect the leaves of Pond Lilies in several ways, the most obvious is that rounded pieces are cut from the leaf pads. At the early stage they stitch this cut part of the leaves together and live between the leaf which they dev...
Caused by:- The Caterpilla of Elophila nymphaeata
Control:- Picking off individuals is possible, as spraying in a pond is not u...

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Common Name:- Chironomid Midges
P_chironomidmidges Chironomid midges are small mosquito-like flies, varying in length from 2 to 18 millimeters depending on the species. Colour and markings also vary with species from pale green to almost black. One distinguishing characteristic common to all speci...
Caused by:- The Maggots of Criotopus species
Control:- Some can be washed off the leaves for fishes to eat. Often the atta...

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Common Name:- Chlorosis
P_chlorosis Chlorosis is the yellowing of the leaves of plants. There are many causes that can cause this effect. One that is the main cause especially in acid soil loving plants is the lack of nutrients like Iron, Manganese, Magnesium and Nitrogen caused by...
Caused by:- Many Causes
Control:- The precise cause must be found before treatment can be initiated, ...

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Common Name:- Chrysanthemum Eelworm
P_chrysanteelworm This eelworm damages the roots of plants like Chrysanthemums, Penstemons, Gypsophila, Phlox and Anemones and are not usually visible. The Damage is not usually noticed until the plant suddenly keels over and dies from the bottom upwards.
Se...
Caused by:- The Nematode Aphelenchoides ritzemabosi
Control:- Control is limited by the availability of chemical treatment, but c...

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Common Name:- Chrysanthemum Leaf Miner
P_chrysantlfminer Chrysanthemums, Gerbias Marguaretes and other related plants leaves are affectedby this maggot. Two to four days after the eggs are laid they hatch and larvae feed between the upper and lower surface of the leaves, making winding, grayish tunnels ...
Caused by:- The Magots of Phytomyza sygenesiae
Control:- With light infestation the maggots can be crushed between the finge...

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Common Name:- Chrysanthemum Petal Blight
P_chrysantpetblight Small water- filled spots or smaller brown spots appear on the petals, eventually spreading to destroy the bloom rapidly. Other Compositae are also affected by this fungus and in edible Burdock it is believed to cause causes Black Streak disease.
Caused by:- The Fungus Itersonilia perplexans
Control:- Most fungus rely on wet humid conditions so aeration between plants...

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Common Name:- Chrysanthemum Ray Blight.
P_chrysantrayblight All parts of the plant ccan be affected, but flower infections start as small reddish?brown or brown spots, often occurring on one side of the flower. Infection spreads rapidly and the whole flower will eventually rot with the affected florets st...
Caused by:- The Fungus Didymella chrysanthemi
Control:- High humidity is sure to encourage this fungus so air circulation i...

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Common Name:- Chrysanthemum White Rust
P_chrysantwhiteblight Chrysanthemum white rust is a serious disease of chrysanthemum which spreads very quickly covering the plants with pustules. It is a quarantine disease in some countries. It produces small white to yellow spots up to 4 mm wide on the upper surfa...
Caused by:- The Fungus Puccinia horiana
Control:- The fungus is encouraged by high humidity with a lack of air circul...

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Common Name:- Clematis Wilt
P_clematiswilt Plants with clematis wilt disease will often suddenly collapse overnight - the foliage turns black (not brown) and the veins take on a purple colour. Clematis can wilt for many reasons such as slugs and snails and even earwigs or caterpillars will...
Caused by:- The Fungus Ascochyta clematidina
Control:- Affected stems should be cut down to ground level and the remaining...

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Common Name:- Clubroot
P_clubroot Club Root is a pernicious disease that can survive in the soil for up to 20 years. It is more prevalent in wet acid soils. The Cruciferae Family which includes all the brassica can be affected by this slime mould. The roots become distorted and sw...
Caused by:- The Mould Plasmodiophora brassicae
Control:- The first line of defence is to burn the infected plants, increase ...

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Common Name:- Codling Moth
P_codlingmoth This moth larva is the famous "worm in the apple" the females of which lay their eggs on the fruit or leaves of fruit trees like apple or pears. Once hatched the larvae eats its way into the fruit to the protein rich seeds and then tunnels its way...
Caused by:- The Larvae of Cydia pomonella
Control:- This pest is difficult to eradicate and a combination of attacks wi...

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Common Name:- Colletotrichum
P_colletotrichum There are many Colletotrichum fungus which are important pathogens to many plants such as cereals, grasses, legumes, vegetables, fruits and ornamental plants around the world. The leaf and stems starts with spots which develop into sunken lesions ...
Caused by:- The Fungus Colletotrichum
Control:- Seeds can transmit this fungus, but prompt removal of affected part...

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Common Name:- Colorado Beetle
P_coloradobeetle The Colorado beetle is an important pest of potato crops and other plants. It is not native to the UK and is a notifiable pest It is approximately 10 mm long, with a bright yellow/orange body and 5 black stripes along the length of each of its w...
Caused by:- The Beetle Leptinotarsa decemlineata
Control:- The Colorado potato beetle has developed resistance to all major cl...

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Common Name:- Copper Deficiency
P_copperdeficiency Copper is an essential nutrient required for the normal growth and development of plants. This explains why about 60 to 70 percent of the copper is found in the chlorophyll. Copper deficiency can result in different symptoms in different plants. T...
Caused by:- Lack of nutrients and or Ph levels
Control:- Foliar feeding and applying a micro nutrient fertiliser will help, ...

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Common Name:- Coral Spot
P_coralspot Coral spot is a fungal disease of woody plants which causes branches to die back. It is usually found on dead wood, this fungal disease will migrate to living tissue after entering via pruning, bark and frost damaged twigs or branches. This rare ...
Caused by:- The Fungus Nectria cinnabarina
Control:- Treatment is difficult so to prevent infection by removal of dead b...

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Common Name:- Crown Gall
P_crowngall Crown gall is a disease of roots and stems and occurs on a large number of plants from cherries to roses. The name is derived from the rough galls that develop at the crown of the plant i.e. the point at the soil line where the main roots join the...
Caused by:- The Bacterium Agrobacterium tumefaciens
Control:- There are over 600 species of plants which are susceptible to crown...

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Common Name:- Crown Rot
P_crownrot There are many types of crown rot some specific to certain plants. The effects of crown rot is that the base of herbaceous plants or trees where the trunk joins the soil will start to rot. The Causal agent is a fungus. Some plants are affected by ...
Caused by:- Usually Phytophthora species
Control:- The most important factor in reducing the threat is to avoid contin...

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Common Name:- Cuckoo Spit
P_couckoospit Cuckoo-spit is the white, frothy substance found on certain plants during the spring and early summer. It is produced by the froghopper nymphs which sucks the sap from the host plants and excrete the excess. The froghopper is an insect and as suc...
Caused by:- The nymph of Philaenus spumarius
Control:- Cuckoo spit is a temporary inconvenience. Once autumn arrives frogh...

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Common Name:- Cucumber Gummosis
P_cucumbergummosis This disease is sometimes called Cucumber Scab. Discrete sunken grey to black spots usually with a mass of dense furry fungal growth appear on the fruit which may split. The stems and leaves may also be affected. At first, a sticky substance is ex...
Caused by:- The Fungus Cladosporium cucumerinum
Control:- Spraying with a suitable fungicide is possible combined with a 2- t...

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Common Name:- Cucumber Mosaic Virus
P_cucumbermosvirus Cucumber mosaic virus (CMV) is one of the most common plant viruses and can infect about 700 plant species and about 90 plant families. The symptoms vary according to the host plant, but can include leaf mosaic or mottling, especially yellow mottl...
Caused by:- A virus.
Control:- There is no known cure for this disease so infected plants should b...

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Common Name:- Currant and Goosebery leaf spot
P_currgsbryleafspot In early summer very small dark brown to black spots develop on the leaves of black currants, red currants and gooseberries. Badly infected leaves turn yellow and drop. The main damage is the defoliation which may occur as early as the end of July...
Caused by:- The Fungus Drepanopeziza ribis
Control:- The fungus lives over winter mainly in fallen leaves. Remove and de...

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Common Name:- Currant Blister Aphid
P_currantblisteraphid Currants especially red currant develops red raised areas that look like welts on its leaves. Currant blister aphids are pale yellow and live on the underside of the leaves in late spring-early summer where they feed by sucking sap. They also secr...
Caused by:- The Aphid Cryptomyzus ribis
Control:- In spring, spray plants with the systemic insecticide kill the emer...

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Common Name:- Currant Clearwing Moth
P_currantclrwngmoth The currant clearwing moth is very similar to the other species of clearwing moth and is found throughout Britain and other parts of the world. It is a very small, day-flying moth that is difficult to see because it is not moth-like in appearance,...
Caused by:- The Larvae of Synanthedon tipuliformis
Control:- Keeping a vigilant eye out for the bore holes in winter to spring a...

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Common Name:- Currant Reversion Virus
P_currantrevvirus Black Currant Reversion builds up slowly which gradually leads to reduced fruit cropping. It is a virus which is spread by the mites (Cecidophyopsis ribis) which causes big bud in ribes species. The mites look like a minute, white grub and are mic...
Caused by:- A Virus
Control:- Once your blackcurrant bushes are infected, its best to dig them up...

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Common Name:- Cutworm
P_cutworm1 Cutworms are larvae of heavy-bodied, night-flying moths. Noctuid moths, in particular those of the turnip moth Agrotis segetum. The older caterpillars feed underground, damaging plant roots and stems, sometimes so badly that the plant topples, hen...
Caused by:- The larvae of Noctuid moths
Control:- Birds eat cutworm larvae. The pesticide diazinon can eradicate a cu...

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Common Name:- Cyclamen Mite
P_cyclmnmite There are several mites that attack cyclamen which all give similar symptoms. Cyclamen mite Phytonemus pallidus(Steneotarsonemus) also known as Strawberry Mite is less than 0.5mm in le...
Caused by:- The Tarsonemid Mite Phytonemus pallidus
Control:- A broad spectrum insecticide may cause more damage than a specific ...

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Common Name:- Cypress Aphids
P_cypressaphids This aphid pest is causes widespread dieback of several popular hedging Cupressus species including Monterey & Italian Cypresses, x Cupressocyparis leylandii (Leyland Cypress), Chamaecyparis lawsoniana, Lawson Cypress, and occasionally Thuja occid...
Caused by:- The Aphid Cinara cupressi
Control:- Spray in early spring even if there is no visible sign of damage, i...

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Common Name:- Cytospora Canker
P_cytosporacnkr Cytospora canker is a fungus disease caused by the fungus Leucostoma persoonii. It affects many different types of trees like aspen, poplar, elm, willow, ash, mountain ash, oak, apple, spruce and stone fruits (e.g., cherry, plum, and peach) and ca...
Caused by:- The Fungus Leucostoma persoonii
Control:- The best control method is to keep the tree in a healthy and vigoro...

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D
Common Name:- Dahlia Smut
P_dahliasmut The symptoms of Dahlia smut are pale brown elongated spots with yellow markings appear on the leaves usually beginning on the lower leaves during cool, wet conditions. As the spots mature they blacken and then die, spores appear on the surface of ...
Caused by:- The Fungus Entyloma dahliae
Control:- The fungus requires very moist conditions to infect and spread whic...

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Common Name:- Damping Off
P_dampingoff Damping off occurs when seedlings suddenly die soon after emerging. Often they show discolouration an deterioration around the base of the seedlings. Some leaves may look waterlogged. Various fungi is the cause as one or more will enter the plant...
Caused by:- Various Fungi
Control:- The major cause of damping off is the inappropriate growing conditi...

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Common Name:- Delphinium Black Blotch
P_delphinblkspot Delphinium Black Blotch is caused by the bacteria Pseudomonas syringae pv. delphinii which can affect Delphinium species and Monkshood and Aconitum. It is rarely fatal, but does reduces the vigour of infected plants especially in wet summers.
Caused by:- The Bacteria Pseudomonas delphinii
Control:- Dispose of affected plants as soon as symptoms are seen.<br /> Spr...

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Common Name:- Delphinium Moth
P_delphiniummoth This moth was originally called P. Moneta. During Spring the shoot tip leaves of Delphinium and Monkshood are stitched together by a fine silken threads by a small green caterpillar with black spots up to 40mm long. The caterpillar then feeds on t...
Caused by:- The Moth Polychrysia esmeralda
Control:- Spraying with a suitable insecticide or pick off the caterpillars w...

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Common Name:- Delphinium Viruses
P_delpniniumvirus There are several viruses that affects Delphiniums most of which gives the leaves a yellowing effect. The ringspot virus gives the leaves a faint yellow rings following the veins of the leaves affected. Irregular yellow spots with yellow banding m...
Caused by:- Various viruses
Control:- Burn infected plants and avoid planting Delphiniums or related plan...

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Common Name:- Delpninium Leaf Miner
P_delpnenlfminer Leafminers are larvae of various insects like small black flies, moths, sawflies or beetles, many of which are specific to certain plants. Phytomyza species is the Delphiium leaf miner whose larvae feed in small groups in the tissues between the u...
Caused by:- The Larvae of some Phytomyza species
Control:- Pick off and destroy all infested leaves. Larvae can sometimes be r...

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Common Name:- Dianthus Anther Smut
P_dianthusanthersmut The anthers of Dianthus species which include Carnations and Pinks become enlarged and dark as they get filled with spores of the fungus. When the anthers split the spores are released to carry on the infection.
Picture from wikimedia Comm...
Caused by:- The Fungus Ustilago violacea
Control:- As the fungus is present throughout the plant the infected plants s...

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Common Name:- Dianthus Fusarium Wilt
P_dianthusfuswilt Most wilts result from excessive transpiration, drying out of soil, bacterial, fungal, or viral problems and involve the vascular system. Two major Wilts are Verticillium wilt and Fusarium wilt. With Fusarium wilt the leaves become lighter green, ...
Caused by:- The Fungus Fusarium oxysporum f.sp.dianthi
Control:- The best way to control Fusarium Wilt is to destroy infected plants...

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Common Name:- Didymella Stem Rot
P_didymellastemrot This infection tends to occurs on the stem at or above the soil-line of tomatoes and related plants, but all parts of the plant can be affected. Dark brown, sunken areas form at the base of the plant and eventually expand to girdle the stem, resul...
Caused by:- The Fungus Didymella lycopersici
Control:- Fungicide sprays can be effective if applied in time. Good plant hy...

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Common Name:- Dieback
P_dieback Dieback disease may refer to a number of plant problems and diseases which directly or indirectly could include acid rain, heavy metal pollution, pathogens like bacteria that produce cankers, physical damage, various Fungi, stem or root rots, nem...
Caused by:- Various Causes
Control:- Identify the cause and treat appropriately, but an initial help to ...

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Common Name:- Dogs
P_dogs In general dogs are not a pest, but many dogs can cause damage to plant or trees. Some may dig up roots, some may scratch or bite off the bark of trees leading to death of the tree, some may urinate on the lower leaves which may scorch them and th...
Caused by:- Various Dogs
Control:- Some problems may be controlled by proper training of the dogs and ...

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Common Name:- Dogwood Anthracnose
P_dogwdanthracnose Dogwood anthracnose is a disease of Dogwood two types that are very suceptable are Cornus florida and C. nuttallii. This causal fungus favours cool damp conditions. Anything that weaken the tree may increase the severity of the disease. Leaf sympt...
Caused by:- The Fungus Discula destructica
Control:- Prune out and destroy affected areas and improve air circulation ar...

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Common Name:- Douglas Fir Adelgid
P_douglasfiradelgid This pest is also known by other names like Gall Adelgid and Cooley Spruce Gall Adelgid as its life cycle is usually completed on at least two genus or species of fir trees over two years and is most prevalent where two susceptible firs are grown ...
Caused by:- The Insect Adelges cooleyi
Control:- The most evident damage caused by this insect is by the first sprin...

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Common Name:- Downy Mildew
P_downymildew Downy mildews are a common plant disease. It can affect all kinds of plants. Downy mildew is often confused with powdery mildew, but they are totally different diseases. Downy mildew is not a true fungi but is more closely related to algae and the...
Caused by:- Mainly Peronospora fungus species
Control:- Cultural control is by growing plants in good conditions, which inc...

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Common Name:- Drought
P_drought Drought is not really a pest, but can be considered as such. There are many causes of drought and the symptoms vary from plant to plant. The most obvious symptom is that the leaves and branches of plants wilt especially on warm days. Poor growth o...
Caused by:- Lack of water in soil
Control:- There are many things that can be done to prevent plants from suffe...

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Common Name:- Dry Rot of Corms
P_dryrotcorms Both these fungi causes dry rot in other species such as crocus, Freesias and Crocosmia, but Gladiolas are very prone to attack by these fungi. Both causes the plant to die-back and wilt sunken spots appear on the corms or bulbs which produce spor...
Caused by:- Stromatinia and Stromatinia gladioli fungus
Control:- Remove infected plants as soon as possible. Inspect stored corms an...

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Common Name:- Dutch Elm Disease
P_dutchelmdis Dutch elm disease, originally identified in Holland in 1920's, hence the name, is one of the most serious tree diseases in the world. It is caused by two related species of fungi Ophiostoma ulmi, Ophiostoma novo-ulmi, the latter being a more virul...
Caused by:- Ophiostoma ulmi and O. novo-ulmi fungi
Control:- Management of Dutch Elm Disease requires a combination of strategie...

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E
Common Name:- Earthworms
P_earthworms Earthworms should never be classed as a pest and is one of the best animals to have in a garden. But in nicely manicured lawns some earthworms (mainly Allolobophora species) excrete worm casts, usually in the autumn, which is a nuisance. Earthworm...
Caused by:- Mailny Allolobophora species of Earthworms
Control:- It is not recommended to use chemical control for worms in the gras...

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Common Name:- Earwigs
P_earwigs There are many species of earwig, but the common European earwig - Forficula auricularia (sometimes called pincerbugs) generally, are not destructive and are not poisonous nor will they not bite or sting humans. They may pinch the skin with their ...
Caused by:- Forficula auricularia
Control:- If they are proving to be a nuisance and you must get rid of them r...

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Common Name:- Eelworms
P_eelworm There are thousands of Eelworm (nematode) species, only a small proportion are plant parasites attacking roots, bulbs, corms, leaves, stems and buds many are beneficial. Some are used in slug control and others eat soil born pests. They are tiny ...
Caused by:- Many Genus and species of nematodes
Control:- Good husbandry and hygiene are essential to help prevent attack as ...

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Common Name:- Elephant Hawk Moth
P_elephanthawkmoth The Elephant Hawk Moth is a large moth with a wingspan of about 45 to 60mm. There are about 18 species recorded in the UK. The adult moths are brounish/green and pink with a streamlined appearance and are usually seen around May to July feeding on...
Caused by:- The Moth Deilephila elpenor
Control:- This pest is a minor one and the moths are so beautiful that it is ...

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Common Name:- Elm Galls
P_elmgall There are many mites(related to spiders) and aphids(insect) that cause galls to occur on elms most affect the upper surface of the leaves where the protrudances disfigure the leaves. Some mites are microscopic and overwinter under the leaf bud she...
Caused by:- Various aphids and mites
Control:- Controlling gall insects is difficult, as any treatment applied aft...

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Common Name:- Enchytraeid worms
P_enchytraeidworms Enchytraeid worms are much smaller than earthworms around 1/4 of an inch(4mm) and are whitish. They are a gardeners friend as the the latest research indicates that they can break down organic matter. They are more usually found in wet acid soils ...
Caused by:- Various Genus of the Family of Enchytraeid worms
Control:- No control necessary, but acidic soils more prone to include this h...

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Common Name:- Eucalyptus Gumtree scale
P_eucalyptusgumscale Eucalyptus Gumtree scale is a sap sucking insect that may have already been introduced to the UK. The female is attached on the stem and the male can move and fly. They infest all parts of the tree and cluster together in colonies. Ants are common...
Caused by:- Scale insect Eriococcus coriaceus
Control:- In other countries Biological control has proved somewhat successfu...

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Common Name:- Eucalyptus Psyllid
P_eucalyptusphylid This Eucalyptus Psyllid is commonly known as the psyllid. It is a yellowish sap sucking insect which has recently been introduce to Europe and the UK. The adults lay their yellow eggs on the tips of young shoots in the Spring. Both nymphal stage a...
Caused by:- The insect Ctenarytaina eucalypti
Control:- Spraying is a possibility on small trees, but with the fast growth ...

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Common Name:- Euonymus Gall
P_crowngall This disease is caused by the same bacteria that causes Crown Gall. It is characterized by the growth of galls (tumor-like swellings) on roots and/or stems. Over 600 species of plants are susceptible to crown gall. The galls are usually rounded wi...
Caused by:- The Bacteria Agrobacterium tumefaciens
Control:- As the bacteria causing this disease is the same as that causing cr...

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Common Name:- Euonymus Mussel Scale
P_euonymusscale1 Adult euonymus scale insects appear as small white or brown, immobile spots on stems and leaves.
The males males about 2mm long and females about 4mm oval and brown. The adults have wings and can fly to mate and infect other plants. The ins...
Caused by:- Unaspis euonymi
Control:- These insects are difficult to eradicate because their waxy coverin...

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Common Name:- European Canker
P_nectriacanker2 The fungus in the advance stages. This fungal species is a frequent cause of cankers in apple, pear, beech and other trees. It produces cankers in the wood of branches and trunks and severe attacks can result in the loss of a branch or the death o...
Caused by:- The Fungus Nectria galligena
Control:- Eradication of this fungi is almost impossible as the spores are al...

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Common Name:- European Gooseberry Mildew
P_eurogsbrymldew There are two mildew that affects gooseberries and related plants as well as Botritis fungus. One is the European(Microsphaera grossulariae) and the other is the American(Sphaerotheca mors-uvae). European Gooseberry Mildew is not considered as a s...
Caused by:- The Fungus Microsphaera grossulariae
Control:- This fungus is encouraged by stagnant air around the branches and b...

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F
Common Name:- Fairy Rings
P_lnfryrng Fairy Rings are also known as fairy circle, elf circle, elf ring or pixie ring and also occupy a prominent place in European folklore as the location of gateways into elfin kingdoms, or places where elves gather and dance. It is a naturally occur...
Caused by:- Various Fungi
Control:- Fairy rings are rarely fatal to lawns.<br /> If fairy rings are no...

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Common Name:- Fasciation
P_fasciation Fasciation is a malformation in plant shoots, roots or flower tips where the growth tend to be thick and flattened. It occurs when something goes wrong with the cells at the growing tips of plants. Instead of growing normally the growing tip sprea...
Caused by:- It has many Causes
Control:- No action is necessary, but if the growth is spoiling a plant it ca...

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Common Name:- Felt Gall Mites
P_feltgallmite Felt Gall Mites is caused by several mites, such as Aceria pseudoplatani which usually attacks Sycamore leaves, that causes Felt Gall. After biting the leaves the mites secrete a substance which causes the leaves to develop fine hairs which are us...
Caused by:- Many Genus and species of Mites
Control:- As the damage to the leaves are caused when the mites bites the lea...

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Common Name:- Figworth Weevils
P_figwortweevil The figwort weevil adults often looks like bird droppings from afar and has a brown/black body and a grey haired head and thorax and about 5mm long. There are one or two velvety black spots on the wing-cases, one in front of the other in the middl...
Caused by:- Various species of Cionus Beetles
Control:- Spraying with a knock down insecticide and a systemic insecticide f...

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Common Name:- Fireblight
P_fireblight Fireblight is a serious disease of the Rosaceae family Which includes apples, Pears and Hawthorn. It was introduce to Eurrope from America in the 1950s. It is a notifyable disease under the EC Plant Health Directive. The symptoms include wilting ...
Caused by:- The Bacteria Erwinia amylovora
Control:- The cause of this disease is a bacterium(Erwinia amylovora) which i...

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Common Name:- Flatworms
P_flatworms There are many genus and species of flatworm native to the British Isle. Many are water living and mostly small. Some live in the soil, but do not cause any damage to plants. Some even attack slugs and other undesirables. Unfortunately two types O...
Caused by:- Various Genus and species.
Control:- It is difficult to eradicate These two New Zealand species when the...

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Common Name:- Flea Beetles
P_fleabeetle There are many types of Flea beetles which are small beetles that jump when disturbed. Some are more specific to certain plants, but do attack other plants as well. They damage crop by chewing holes in the leaves usually from the top. They attack ...
Caused by:- Various genus and species of small beetles
Control:- Keeping the growing conditions as good as possible as stressed plan...

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Common Name:- Fomes Fungi
P_fomesfungi This name is another name for the FOMES FUNGI. There are several species of Fomes fungi which attack a variety of trees. from Apple to Pine trees, and causing fungal fruiti...
Caused by:- Several species of Fomes Fungi
Control:- There is little that can be done except pruning out the infected br...

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Common Name:- Forsythia Gall
P_forsythiagall Crown Gall(Agrobacterium tumefaciens) can cause galls on Forsythia as well as the fungus Phomopsis species.
Phomopsis species galls are light brown and irregularly shaped with a bumpy, rough texture. The galls range in size from 5mm to 30mm...
Caused by:- The Fungus of Pomopsis Species
Control:- There are no chemical controls for Phomopsis canker or gall.<br /> ...

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Common Name:- Foxes
P_foxes Foxes are increasingly entering gardens and setting up home, especially if there is some shelter where there is soft sandy soil or if there is a bank where they can dig into to create a den. The damage they do is often horrendous. The other damage...
Caused by:- The fox Vulpes vulpes
Control:- They are some propriety scents that can repel most foxes, but these...

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Common Name:- Frost
P_frost Frost is one of the gardeners best friend, unfortunately if you do not plan properly it can also be one of the gardeners worst nightmares. Frost forms when the temperature for whatever reason falls below 0 degrees Centigrade. Whether friend or fo...
Caused by:- Temperatures below 0 degrees Centigrade
Control:- There are many things that can be done to protect tender plants. On...

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Common Name:- Fuchsia Rust
P_fuchsiarust Fuchsia rust is a fungus disease that spreads by airborne spores and need other genus such as Abies (fir) and willowherbs (Epilobium spp.) to complete its life cycle. Fuchsia is related to willowherb and will be affected by the fungus as well. Th...
Caused by:- The Fungus Pucciniastrum epilobii
Control:- In the European Community the products permitted under organic regi...

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Common Name:- Fungus
P_fungus There are well over 1 million known fungi and every part of this world has some fungus that is native or common to that area. Also every living thing including fungi are is predated upon or affected by other fungi.
Fungi are members of a la...
Caused by:- Various fungi
Control:- There are several ways Fungi can be erridacated such as fungicides,...

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Common Name:- Fungus Gnats
P_fungusgnats Fungus gnats are small black flies(around 2mm), which are also known as Sciarid Flies or mushroom flies.They are a common pest on or near the surface compost of houseplants. They run o...
Caused by:- Many Genus and species of the Order Diptera
Control:- Allow the surface of composts to dry out a little before watering t...

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Common Name:- Fusarium Bulb Rot
P_fusariumbulbrot Fusarium bulb rot is caused by several species of Fusarium fungi which can live in the soil for years. It causes rot in many kinds of bulbs including Gladioli, Garlic, Onion, Daffodils and many more. The Symptoms and species of fungi tend to vary ...
Caused by:- Several species of Fusarium fungi.
Control:- One way to reduce the incidence of Fusarium bulb rot is to wash the...

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Common Name:- Fusarium Wilt
P_dianthusfuswilt Fusarium wilt disease is caused by many fusarium species living in the soil. Some of the Fusarium species like fusarium oxysporum has many special forms (f.sp.) which tend to mainly, but not exclusively, attack specific solanaceous plants like the...
Caused by:- Several species of Fusarium fungi.
Control:- Because Fusarium fungi are widespread and persist for several years...

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G
Common Name:- Gall Wasps
P_oakglwsp Gall Wasps is the name given to more than 1200 insects of many genus and species of the suborder Apocrita, family Cynipidae. These wasps usually have the typical thin waist between the thorax and abdomen. When the larvae of these wasps bite and ca...
Caused by:- Insects species of the Suborder: Apocrita Family:
Control:- Remove all infected stems by cutting back to well behind the galls ...

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Common Name:- Galls
P_galls Plant galls are abnormal growths of plant tissues and can be caused by a large variety of parasites, fungi, bacteria, insects, mites and damage to the plant. They are often highly organised structures from which the cause of the gall can often be ...
Caused by:- Many parasites, fungi, bacteria, insects, mites an
Control:- The exact cause of the galls must be determined before specific tre...

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Common Name:- Ganoderma Fungi
P_ganodermafungi There are several species of bracket fungi of the genus Ganoderma which causes of decay in the heartwood of a very wide range of tree and palm species all over the world. The rot is usually in the lower 4-5 feet of the trunk where the bracket frui...
Caused by:- Various species of Fungi from the genus Ganoderma
Control:- Apart from removing the bracket fruiting bodies to prevent the spre...

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Common Name:- Geranium Sawfly
P_geraniumsawfly1 A Greenish-grey, caterpillar-like larvae with black heads that live on the underside of Geranium leaves where they make rounded holes in leaves, but not in Pelargonium leaves, which are usually called Geraniums. Damage occurs during May to Septemb...
Caused by:- Protoemphytus carpini
Control:- Spray with a systemic insecticide, but usually the damage is only c...

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Common Name:- Geum Sawflies
P_geumsawfly At least three sawflies attack the leaves of Geums. One the Common Sawfly (Metallus lanceolatus) is a leaf miner that eats the leaves from inside. The tracks eventually merge together then dies leaving large brown patches on the leaves. The larvae...
Caused by:- A few Genus of insects from the Family Tenthredini
Control:- For the leaf-mining sawfly a systemic insecticide is probably the o...

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Common Name:- Gladiolus Corm Rots
P_gladioluscormrot It is a wonder that Gladiolus manage to grow and survive as the corms are affected by several fungi, bacteria and viruses which have deleterious effects on the corms:-

Dry Rot:-
Corms infected with the fungus Fusarium oxysporum f.s...
Caused by:- Various fungi and Bacteria
Control:- Control Management includes starting with healthy stock, removal of...

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Common Name:- Gladiolus Rust
P_gladrust Gladiolus Rust is caused by the fungus Uromyces transversalis and is an obligate parasite that only grows and reproduces on members of the family Iridaceae, including Gladiolus, Tritonia, Crocosmia and Watsonia spp. It primarily attacks hybrid cul...
Caused by:- The Fungus Uromyces transversalis
Control:- In the European Community the products permitted under organic regi...

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Common Name:- Gladiolus Thrips
P_gladiolusthrips Pear thrips, Taeniothrips inconsequens (Uzel, 1895) Picture by Pennsylvania Department of Conservation and Natural Resources - Forestry Archive, Bugwood.org.
Plants severely infested with gladiolus thrips looks spotted and bleached with sil...
Caused by:- The Insect Taeniothrips simplex
Control:- During winter the corms should be stored in cold temperatures which...

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Common Name:- Gleditsia Pod Gall Midge
P_gledpgallmidge Gleditsia Pod Gall Midge causes reddish galls to occur at the tips of the branches of the Honey Locust tree(Gleditsia triacanthos). Leaflets become pod-like where they have been damaged by the midge inside this pod the larvae continue feeding and ...
Caused by:- The Insect Dasineura gleditchiae
Control:- The severity of the attack depends to a certain extent on the varie...

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Common Name:- Gloeospporium Fruit Rot
P_gloeosporiumfrot Glomerella, or bitter rot, is a fungal disease which occurs on many fruit throughout the world. It is often referred to as a ‘summer rot’. It is caused by the Glomerella cingulata fungus which is the sexual stage of this fungus while the asexu...
Caused by:- The Fungus Glomerella cingulata
Control:- Warm, wet, humid conditions are ideal for the Glomerella fungus. Pr...

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Common Name:- Goosbeberry Sawfly
P_bsbrysawfly The common gooseberry sawfly larvae(Nematus ribesii) is one of at least three sawflies larvae that can strip the leaves from Gooseberry bushes in as little time as three weeks. Two others are the pale gooseberry sawfly (Pristiphora pallipes) and t...
Caused by:- The larvae of several Sawflies.
Control:- Continued vigilance is necessary as the sawflies are difficult to c...

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Common Name:- Gooseberry Dieback
P_gsberrydieback Gooseberry Dieback can be caused by at least two fungi Botrytis cinerea(Botryotinia fuckeliana) and Eutypa lata which usually attack grapevines. With Botrytis there is a greyish mould covering a branch or fruits eventually the branch dies back. Th...
Caused by:- Various Fungi
Control:- Pruning out infected branches and burn the cuttings. Spraying with ...

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Common Name:- Gooseberry Mildew
P_gseberrymldew There are two mildew that affects gooseberries and related plants as well as Botritis fungi. One is the American(Sphaerotheca mors-uvae) and the other is the European(Microsphaera grossulariae). American Gooseberry Mildew is a much more vigorous f...
Caused by:- Varius fungi
Control:- This fungus is encouraged by stagnant air around the branches and b...

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Common Name:- Gooseberry Rust
P_goosebyrust Gall produced by Nettle Clustercup Rust fungus Puccinia caricina DC. on common nettle Urtica dioica L.
The Genus Puccinia causes rust in many plants. In Gooseberry the species is P.Caricina which is a parasitic fungi that grow on gooseberry...
Caused by:- The Fungus Puccinia caricina
Control:- In the European Community the products permitted under organic regi...

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Common Name:- Gorse Seed Weevil
P_gorsesdwvil The Gorse Seed weevil Exapion ulicis (formerly Apion ulicis) is a species of straight-snouted weevil native to Europe. It was one of the first biological pest control against the spread gorse (Ulex europaeus) in New Zealand in the 1950s. The preda...
Caused by:- The Weevil Exapion ulicis
Control:- These pests do not cause enough damage to warrant spraying as the G...

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Common Name:- Grapevine Dieback
P_gpvinedieback Grapevine dieback usually does not happens until the vine has been growing for some years. In the spring when shoots from infected wood become stunted with small, chlorotic, distorted leaves. The leaves become more tattered as the season progresse...
Caused by:- The Fungus Eutypa lata
Control:- The disease is introduced into the vines during wet weather when sp...

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Common Name:- Green Spruce Aphids
P_greenspruceaphis Green spruce aphid Elatobium abietinum is a sap-sucking insect that infests spruce trees(Picea species). They are up to 2mm long and is dull green with dark red eyes and is most likely to be seen on spruce trees during Autumn to Spring. Eggs are p...
Caused by:- The Aphid species Elatobium abietinum
Control:- If the tree is not too large spray with insecticide, both knock dow...

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Common Name:- Greenfly
P_greenfly Greenfly is one of many species of aphids which suck the sap from leaves and stems and secrete honeydew which makes the leaves below sticky with honeydew which is the sugary sap of the plant. They attract ants and honeybees which feeds on the hone...
Caused by:- Several species of Aphids
Control:- Spray with insecticide, both knock down or systemic or wash plants ...

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Common Name:- Greenhouse Whiteflies
P_ghsewhiteflies The glasshouse whitefly is a common sap-feeding pest of houseplants and greenhouse plants like:- cucumber, melon, tomato, peppers, Chrysanthemum, Pelargonium, and Verbena. but there are several other whiteflies that tend to specifically attack oth...
Caused by:- The Insect Trialeurodes vaporariorum
Control:- Due to this pest's rapid reproductive rate there are widespread occ...

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Common Name:- Grey Mould
P_mildew1 Grey mould(also called Botrytis) is a disease usually caused by the fungus Botrytis cinerea(Botryotinia fuckeliana). This fungus has a diverse genetic variability(polyploidy) and some strains are specific to one type of plant. It normally affects ...
Caused by:- The Fungus Botrytis cinerea(Botryotinia fuckeliana)
Control:- Controlling this fungus is often difficult as it is so widespread s...

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Common Name:- Grifola frondosa
P_grifolafrondosa Grifola frondosa is usually, but not exclusively, a parasitic edible bracket fungi of the oak tree and gets its nutrients from the roots of its host. It is also known by many common names like Hen of the Woods, Ram's Head, Sheep's Head and Maitake...
Caused by:- The fungus Grifola frondosa
Control:- Apart from removing the fruiting bodies to prevent its spread. Ther...

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Common Name:- Ground Beetles
P_grndbeetles Ground Beetles also known as Carabid Beetles are mainly carnivorous and feed on other garden pests like aphids, caterpillars, slugs, snails, crane flies (leatherjackets), fruit flies, gall midges, many other garden pests. Therefore they should be ...
Caused by:- Various Carabid Beetles
Control:- As a general rule nothing needs to be done about ground beetles, bu...

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Common Name:- Gummosis
P_gummosis Gummosis is the abnormal production of a sticky gum or liquid in certain trees and fruits, esp stone fruit trees like plum, cherry and peaches. It has many causes and can be the result of wounding, infection by bacteria or pruning. Gummosis is mo...
Caused by:- Several Causes
Control:- To control this problem there must be several methods employed. Goo...

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Common Name:- Gypsy Moth
P_gypsymoth The gypsy moth caterpillars feed on almost any hardwood trees, with the exception of ash. when there is a large infestation they can cause immense defoliation of trees and conifers in an area leading to reduced growth and vigour and death of the a...
Caused by:- The Larvae of the moth Lymantria dispar
Control:- Phermone traps may be used to trap the males, Spraying with insecti...

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H
Common Name:- Hawthorn Button Top Gall Midge
P_hawthornbtgmidge Hawthorn Button Top Gall Midge is a common gall midge which lays its eggs in the shoots of Hawthorn in June. The developing larva produces a hormone which causes the developing shoots to develop into a rosette of small leaves instead of the normal...
Caused by:- The Gall Midge Dasineura crataegi
Control:- Spraying with an insecticide at the larval stage in order to preven...

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Common Name:- Hebe Downy Mildew
P_hebedwnmildew Hebe Downy Mildew is caused by the fungus Pseudoperonospora griesea and is not a true fungi but is more closely related to algae. Downy mildew will not usually kill the Hebe as it needs a living host to survive and reproduce. The growth is felt li...
Caused by:- The Fungus Peronospora grisea
Control:- The best method of control is prevention therefore good hygiene and...

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Common Name:- Hellebore Black Death
P_hellblkdth Hellebore Black Death is a relatively new disease, in the past 20 years, affecting Hybrid Hellebores. It is believed to be caused by a virus of the Carlavirus family given the name Hellebore Net Necrosis Virus (HeNNV).
The symptoms appear f...
Caused by:- The Virus Hellebore Net Necrosis Virus (HeNNV)
Control:- As with any plant virus infections there are no chemical controls.<...

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Common Name:- Helleborus Leaf Blotch
P_heleborelblotch Very few diseases affect Hellebores( Christmas Rose or Lenten Rose), but leaf blotch is an unsightly brown or black areas or blotches which appear on the leaves and stems of this plant. These blotches may merge leaving larger dead parts of the lea...
Caused by:- The Fungus Coniothyrium hellebori
Control:- It is often difficult to cure this fungus with fungicide therefore ...

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Common Name:- Hemerocallis Gall Midge
P_hmcallisgalmidge Very few things affect the Day lilies(Hemerocallis), but a major pest which seems to effect mainly the early-flowering Daylily buds is the Hemerocallis Gall Midge.
They are small flies which lays hundreds of eggs in the developing Daylily f...
Caused by:- The Larvae of the Insect Contarinia quinquenotata
Control:- Because they are inside the galled buds, larvae are protected from ...

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Common Name:- Hemispherical Scale Insect
P_hemisphscale Hemispherical scale insects is mainly a tropical pest, but it is also a pest in warm greenhouses and homes. It is a sap sucking insect that feed on plant juices and cause a loss of vigor and leaf deformations. Depending on the many host plant and ...
Caused by:- The scale Insect Saissetia coffeae
Control:- Small infestations can be rubbed off with the fingers. They are rel...

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Common Name:- High Temperature Damage to Plants
P_heatdamage Sun and Heat damage to plants can cause more subtle effects than those of extreme cold, which will kill a plant very quickly. Exposure to too much sun can generate very high temperatures in plant tissues, leading to dehydration and death of tissue...
Caused by:- Too much Sun
Control:- Once the damage is done there is little that can be done apart from...

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Common Name:- Holly Leaf Miner
P_hollylminer This pic shows the leaves of Ilex aquifolium with Phytomyza ilicis. There are several Phytomyza leaf miners some of which are particular to certain countries and specific Hollies. Phytomyza ilicis, is a European species and most hollies have some ...
Caused by:- The Larva of Phytomyza ilicis
Control:- Although the mines are unsightly, this pest can be tolerated as it ...

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Common Name:- Holly Tortrix Moth
P_hollytormoth This moth is a common species throughout the British Isles, occupying a wide variety of host plants. The adults are quite variable, and fly between June and September. They are active in the evening and later come towards light. It is also known a...
Caused by:- The Larvae of Rhopobota naevana
Control:- Insecticidal winter oil wash spraying should be effective in contro...

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Common Name:- Hollyhock Rust
P_hollyhockrust This rust fungus is a major problem of hollyhocks. It is caused by the fungus Puccinia malvacearum which only attacks Hollyhocks and their relative the common Mallow(Malvs rotundifolia). This infection is one of the major reasons why this wonderfu...
Caused by:- The Fungus Puccinia malvacearum
Control:- It is important to break the disease cycle and remove infected leav...

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Common Name:- Holm Oak Leaf Miner
P_holmoaklminer There are a few leaf miners that attack Holm Oak, but only one(Ectoedemia heringella) is specific to the evergreen Holm Oak. Two others are Phyllonorycter messaniel-la (Oak Leaf-Miner) which is more widespread and Stigmella suberivora (a micro mot...
Caused by:- Several Leaf Miner Moths
Control:- There is usually very little that can be done as insecticidal spray...

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Common Name:- Honey Fungus
P_honeyfungus1 There are many species of the saprophytic and or parasitic Honey Fungus(Armillaria). These fungi are some of the most destructive fungi for trees and other woody herbaceous perennials. One species(A. ostoyae) in the USA state of Oregeon is now est...
Caused by:- Several Species of the Fungus Genus Armillaria
Control:- Following the EU Directive 91/414/EEC on plant protection products ...

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Common Name:- Honeydew
P_honeydew Honeydew is a sugar-rich substance secreted by many sap sucking insects as they feed on a plant or tree. Their mouthpart penetrates the phloem of the leaf or plant and the high-pressure of the sap is forced into the gut of the animal. The insect u...
Caused by:- Various Sap Sucking animals
Control:- Spraying the plant with insecticide at the first sign of the sap su...

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Common Name:- Honeysuckle Aphids
P_honeysuckleaphid There are two species of aphids, a sap sucking insect, from the Genus Hyadaphis that are the most troublesome pests of honeysuckle. These are H. tataricae a white/cream aphid and H. passerinii a grey/green aphid.
The toxins released by the ...
Caused by:- Species of Hyadaphis aphids
Control:- Several things can be done to lessen attacks from this pest. In the...

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Common Name:- Horse Chestnut Bleeding Canker
P_hschntblcanker Horse Chestnut Bleeding Canker is a disease of the bark of horse chestnut which is caused by the bacterium Pseudomonas syringae pathovarv aesculi. It causes cankers which bleed a dark or reddish brown sticky fluid that ooze from cracks in the bark...
Caused by:- The Bacteria Pseudomonas syringae pv. aesculi
Control:- It is believe that this disease has been imported from India where ...

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Common Name:- Horse Chestnut Leaf Blotch
P_horsechstlfblotch Horse Chestnut Leaf blotch is a relatively common fungal leaf disease caused by fungus Guignardia aesculi. The initial infections looks like as water-soaked areas, starting at the edges of the leaf then darkens and spreads to the midrib. This area...
Caused by:- The Fungus Guignardia aesculi
Control:- The fungus survives in infected leaf tissues throughout the winter ...

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Common Name:- Horse Chestnut Scale
P_horsechstscale Horse Chestnut Scale(Pulvinaria regalis) is a sap feeding insect that feeds on several species of trees including Sycamore (Acer pseudoplatanus), Lime (Tilia), Magnolia(Magnolia species) and Horse Chestnut (Aesculus). It was first noticed in the U...
Caused by:- The Scale insect Pulvinaria regalis
Control:- As most of the host trees are very large it is often tolerated, but...

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Common Name:- Hosta Virus X
P_hostavirusx This virus is believed to have appeared around 1998 and has spread around the world like an epidemic. Hostas infected with Hosta Virus X usually, but not always. look weak, wilty and/or puckered. This virus affects different hosta cultivars in dif...
Caused by:- A relatively new virus
Control:- There is no cure and you should not compost infected plants as it r...

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Common Name:- Hoverflies
P_hoverflies Hoverflies are not pests, but are one of the gardeners best friends like the ladybirds and the lacewings, because the larva eats aphids and other soft bodied pests. The adults feed on pollen and nectar from flowers and some hoverflies are importan...
Caused by:- Several Genus and species of the family Syrphidae
Control:- Care should be exercised in the use of insecticides during the Spri...

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Common Name:- Hydrangea Leaf Spot
P_hydranglfspot There are many fungal leaf spot diseases of Hydrangeas. One very common one is caused by the fungus Cercospora hydrangeae others by Phyllosticta, and Colletotrichum fungi. All have similar signs and symptoms.. This fungal leaf spot can affect mos...
Caused by:- Several fungi, but mainly Cercospora hydrangeae
Control:- There are many fungal leaf spot diseases of Hydrangeas. One very co...

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Common Name:- Hydrangea Powdery Mildew
P_hydrpowmild Powdery mildews are one of the most widespread plant diseases. They affect virtually all kinds of plants from cereals and grasses, to fruit trees, and broad-leaved shade trees.
The symptoms are usually the same or very similar regardless of...
Caused by:- The Fungus Microsphaera polonica
Control:- The best method of control is good hygiene and growing conditions, ...

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Common Name:- Hydrangea Scale
P_hydrangscle This sap sucking scale insect also attacks other trees such as Prunus and Acer. The scale insects are most noticed in the early spring when the female lays the eggs under the leaves amongst a mass of white cottony waxy fibers. The egg masses are ...
Caused by:- The Scale insect Pulvinaria hydrangeae
Control:- The best way to deal with them is to spray with an insecticide in e...

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I
Common Name:- Inonotus Fungi
P_inonotusfgi Inonotus genus of fungi contain over 100 species which are parasitic/saprophytic mainly on broadleaf trees around the world. Most produce an annual fruiting body which has a felt-like upper surface starting off yellow/orange eventually turning bro...
Caused by:- Several species of Inonotus Fungi
Control:- The main way of avoiding these fungi is to avoid damaging the bark ...

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Common Name:- Iris Borer Caterpillars
P_irisborer Although these are not as yet in the UK it is only a matter of time before they may invade these shores. Iris borers(Macronoctua onusta) spend the winter as eggs on dead leaves, stalks and plant debris at the base of irises. In spring, they hatch ...
Caused by:- The Moth Macronoctua onusta
Control:- There are several things that can be done about this pest. First of...

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Common Name:- Iris Ink Disease
P_irisinkdisease This disease mainly attacks bulbous irises and a few other genus like Lachenalia and Tritonia. On the bulbs blue/black streaks, with raised margins, appear on the outer layers. Badly affected bulbs may rot or dry out. On the leaves initially chlor...
Caused by:- The Fungus Drechslera iridis
Control:- Destroy bulbs in which fleshy scales are affected and remove any i...

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Common Name:- Iris Leaf Spot
P_irislfspot Iris leaf spot is caused by a fungus called Mycosphaerella macrospora (formerly Didymellina macrospora or sometimes Heterosporium iridis) that is spread by wind blown spores or water splashes. It is more common during wet seasons and encouraged by...
Caused by:- Mycosphaerella macrospora
Control:- This fungus survives the winter on infected plant parts, therefore ...

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Common Name:- Iris Mosaics Virus
P_irismosicvir There seems to be many types of Iris Mosiac Virus, but the patogenic virus appear to be similar and also similar to Cucumber Mosiac Virus. Three types of Iris mosiac viruses are classified as affecting bearded virus depending on the severity of th...
Caused by:- Possibly several viruses
Control:- There is no cure or control other than to control the aphids and re...

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Common Name:- Iris Rhizome Rot
P_irisrhzmerot Iris Rhizome soft rot is often caused by the bacterial pathogen Erwinia carotovora. Usually the first sign you see is some of the leaves abruptly turning yellow and falling over. If you pull on the leaves you notice the rhizome at the base of the ...
Caused by:- The Bacteria Erwinia carotovora
Control:- If the infection is caught early enough cutting away the unhealthy ...

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Common Name:- Iris Rust
P_irisrust Iris rust is caused by the puccinia iridis fungus. It causes round to oval rust-colored pustules surrounded by a yellow margin. These spots can be present on leaves and stems, and initially do not kill the plant, but the leaves die prematurely an...
Caused by:- The Fungus Puccinia iridis
Control:- Spraying with a fungicide especially a systemic one should control ...

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Common Name:- Iris Sawfly
P_irissawfly The Iris Sawfly (Rhadinoceraea micans) is a black fly similar in shape to a hoverfly. These saw flies can be seen resting on the irises in late spring to summer. They seem to prefer waterside Irises especially the yellow variety. The larvae or cat...
Caused by:- The Sawfly Rhadinoceraea micans
Control:- Spraying with insecticides is possible where there is no danger fro...

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Common Name:- Iris Scorch
P_irisscorch Scorch is a pathological condition of bearded irises and the cause is unknown, but the bacterium Pseudonwnas that is also found in lilies is suspected to be the cause. The first sign of the disease is that the leaves, mainly at the center of the p...
Caused by:- Unknown cause, but Bacteria suspected
Control:- To avoid Iris Scorch dig up the affected plants and place them in a...

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Common Name:- Iron Deficiency
P_irondeficiency1 Iron deficiency is not a pest as such, but is a symptom that there is something wrong, usually with soil nutrients. It can easily be mistaken for manganese deficiency, but in this case all leaves are usually affected. All plants need iron to grow,...
Caused by:- Usually due to Soil ph being above 7
Control:- Iron deficiency can be avoided by choosing appropriate soil growing...

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Common Name:- Ivy
P_ivy Ivy is not a pest as such, but is considered so by many due to its fast growth and climbing action with self clinging roots. If left unchecked it will grow up trees and eventually block out the light and may even strangle the growth of the tree. I...
Caused by:- Fast Climbing Growth of Ivy
Control:- Annual pruning and removal of dead leaves is needed o keep it in ch...

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Common Name:- Ivy Leaf Spot
P_ivylfspot There are several bacteria and fungi that causes leaf spot on Ivy leaves. Bacteria enters through wound damage or through natural openings. usually it is the older leaves that develop water-soaked spots that turn brown then black. Some bacteria ca...
Caused by:- Various Fungi and Bacteria Xanthomonas spp.
Control:- To prevent leaf spot the most effective, apart from spraying with f...

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J
Common Name:- Juniper Aphids
P_junipaphids Aphids are insects that suck the sap from any trees it lives on.
In the case of juniper there are at least five Cinara species that attack juniper depending on where in the world the tree is located. These are Cinara cupressi C. fresai C. j...
Caused by:- Various species of Cinara aphids.
Control:- Washing the aphids from the leaves with a strong water jet will wor...

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Common Name:- Juniper blight
P_juniperblight Juniper blight often called "Juniper tip Blight" is causes by the fungus Phomopsis juniperovora which causes juniper branches to turn light brown and gradually die back in late spring and summer. Small pinhead sized black, fruiting bodies containi...
Caused by:- The Fungus Phomopsis juniperovora
Control:- Infected twigs and branches should be pruned about 50mm into live w...

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Common Name:- Juniper Pear Rust
P_pearjnprst3 Juniper Pear Rust is caused by the rust fungus Gymnosporangium sabinae(G. fuscum). Like most rust diseases it requires two different host to complete its life cycle from year to year. With this fungus juniper is the winter host and pear is summer...
Caused by:- The Fungs Gymnosporangium sabinae
Control:- It is important to break the disease cycle and remove infected leav...

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Common Name:- Juniper Scale
P_juniperscale1 Flat rounded or elongate and rectangular white patches with a small yellowish patch on leaves.
See these other Scale insects Azalea Bark,
Caused by:- The Scale insect Carulapsis juniperi
Control:- Spray forceably with perimetrin or other knock down insecticide.

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Common Name:- Juniper Webber Moth
P_junprwebmoth The larvae or caterpillar of the moth Dichomeris marginella after hatching eats the the internal foliage while living in a communal web. It is a very light brown body with dark stripes above and below and is up to 14 mm long. The leaves dries up a...
Caused by:- The Caterpillar of the moth Dichomeris marginella
Control:- Spraying with an insecticide ensuring the insecticide gets into the...

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K
Common Name:- Kabatina Tip Blight
P_kabatinatpblght Kabatina tip blight is caused by the fungus Kabatina juniperi which infects Juniper, Thuja, Abies, Cupressus, Cupressus, and Taxus species. This blight affects the shoots in the season followimng that in which it was infected. Early in the spring...
Caused by:- The Fungus Kabatina juniperi
Control:- Prune out dead and infected twigs and branches to at least 50mm int...

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Common Name:- Keithia Thujina Needle Blight
P_cdrlfblight Didymascella thujina is an ascomycete fungi from the family of Hemiphacidiaceae, which causes Cedar leaf blight (or Keithia Thujina needle blight disease, after the original genus name) in several cedar(Thuja) species. The disease is indigenous to...
Caused by:- The Fungus Didymascella thujina(Keithia thujina)
Control:- Control of the disease can be effective with certain fungicides and...

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Common Name:- Knopper Gall of Acorns
P_acornglwsp The Acorn Gall wasp(Andricus quercuscalicis) causes Knopper Galls of Oak(Quercus) acorns. The wasp lays its egg on a developing acorn in early Summer. When the egg hatches the grub secretes chemicals which causes the acorn to develop into a gall. ...
Caused by:- The Wasp Andricus quercuscalicis
Control:- Unless the infection is great spraying is not necessary as most Oak...

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L
Common Name:- Laburnum Leaf Miners
P_labmnlfmnr The larva of the moth Leucoptera laburnella and the leaf mining fly Agromyza demeijerei mines the leaves of laburnum and their hybrids. The larvae of the moth Leucoptera mines the leaves in the center of the leaves and do so mainly in circles, whe...
Caused by:- The Moth Leucoptera laburnella and fly Agromyza demeijerei
Control:- Spraying with a systemic insecticide during an attack should reduce...

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Common Name:- Lacewings
P_lacewings Lacewing insects are not pests and are one of the gardeners friends like the ladybird and the hoverflies, because the larva and the adults eats aphids and other soft bodied pests with their biting and sucking mouth parts. The adults also feed on p...
Caused by:- Predatory Insects of the Chrysopidae family
Control:- Gardeners can attract lacewings, and therefore their larvae, to gar...

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Common Name:- Lackey Moth
P_lackeymoth The larvae of the Lackey Moth feed gregariously, on the leaves, inside a web tent of silk, in which they regulate their temperature, on many trees such as Apple(Malus) and Pear(Pyrus), hawthorn (Crataegus), blackthorn (Prunus spinosa), oak (Querc...
Caused by:- The Larvae of the Malacosoma neustria Moth
Control:- The best way to control the moths is to remove the tents with the c...

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Common Name:- Ladybirds
P_ladybirds Ladybirds are one of the gardeners best friends as both larva and adult each eat many hundreds of aphids in its lifetime. Worldwide there are about 5000 species, but not all of them are brightly coloured and spotty; some are really quite dull look...
Caused by:- Several Species from the Family Coccinellidae
Control:- Many Gardeners make special ladybird winter quarters to entice lady...

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Common Name:- Laetiporus Fungi
P_laetiporusfgi Laetiporus sulphureus is a species of edible mushrooms found throughout much of the world. It causes a brown heart rot in the wood of large standing and fallen hardwoods and some softwoods such as Apple Beech, conifers, Larch, Oak, Willow, and Ye...
Caused by:- The Fungus Laetiporus sulphureus
Control:- The fungus can be disrupted by removing the fruiting bodies and spr...

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Common Name:- Larch Wooly Adelgid
P_lrchwlyaldgid The Larch Wooly Adelgid, is found anywhere in the world where Spruce and Larch are grown, where it feeds on the needles of larch and on the buds of spruce. In summer on Larch, when the infestation is greatest, the infested foliage appears to be co...
Caused by:- The insect Adelges laricis
Control:- This adelgid can be controlled on small to medium ornamental trees ...

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Common Name:- Large Rose Sawfly
P_lgerseswfly The adult of Arge pagana. Picture by beentree from Wikimedia Commons.
There are two Arge species referred to as the Large Rose Sawfly and several Arge species which look very similar in the larval state. The two Large Rose Sawflies are Arge...
Caused by:- The Sawflies Arge pagana and A. ochropus
Control:- If the infestation is light when spotted, the larvae can be removed...

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Common Name:- Lavender Shab
P_lavshab Lavender Shab is a fungal disease caused by Phomopsis lavandulae that is common in Europe, but not throughout the world. The spores are carried in the air and infect the plants, initially causing shoots to wilt. This fungus kills the stems of the ...
Caused by:- The Fungus Phomopsis lavandulae
Control:- If only a few branches are affected it might be possible to save th...

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Common Name:- Lavetera Leaf Spot
P_lavateralfspt Lavatera leaf spot is usually, but not exclusively, a fungal disease that starts with small red/brown necrotic areas that develop on the stems and leaves, usually starting at ground level and which rapidly enlarged within a few days. It may surrou...
Caused by:- The Fungi Colletotrichum malvarum
Control:- This disease is difficult to control, but if caught early and spray...

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Common Name:- Lawn Fairy Rings
P_lnfryrng Fairy Rings are also known as fairy circle, elf circle, elf ring or pixie ring and also occupy a prominent place in European folklore as the location of gateways into elfin kingdoms, or places where elves gather and dance. It is a naturally occur...
Caused by:- Various Fungi
Control:- Fairy rings are rarely fatal to lawns.<br /> If fairy rings are ...

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Common Name:- Leaf and Bud Eelworms
P_lfandbdelwrm There are several Genus and species of leaf and bud eelworms which are microscopic nematodes and not visible to the naked eye. They causes the foliage to turn yellow in patches between the leaf viens, which then turn brownish-black without the for...
Caused by:- Various Genus and species of Nematodes
Control:- Keep the leaves and stems of your plants reasonably dry as wet foli...

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Common Name:- Leaf Cutter Bees
P_lfcutbees Leafcutter bees are important native pollinators and are not aggressive only stinging when handled. The sting is not as powerful as other bees or wasps. They are a little nuisance though, because they cut circular pieces from the the leaves of Ros...
Caused by:- Megachile rotundata and related species.
Control:- It is usually not necessary to get rid of these bees as the damage ...

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Common Name:- Leaf Miner
P_leafminer1 There are many types of leaf miners that feed between the tissues of leaves. Leaf miners can be beetles(Coleoptera), (flies(Diptera), sawflies(Hymenoptera) and moths(Lepidoptera). The precise pattern of the feeding tunnel between the upper and low...
Caused by:- Several species of Insects
Control:- If there are only a few leaves affected you can pick them off and d...

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Common Name:- Leaf Scorch
P_leafscorch Leaf Scorch of trees is usually a warning that some of the growing condition is adversely affecting the Tree and is most often restricted entirely to the edges of the leaves. It is often called a disease, but is not usually caused by fungus, bacte...
Caused by:- Various non disease conditions
Control:- This condition is not usually too harmful to the tree as by the tim...

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Common Name:- Leaf Spot
P_leafspot Leaf infections called "leafspots" are caused by a variety of fungi and some bacteria on many trees, shrubs and perennials. There are basically two types of leaf spots one caused by fungi and another caused by bacteria. A leaf spot diseases causes...
Caused by:- Various Fungi and Bacteria
Control:- If leaves are severely infected they can be pruned out and fallen l...

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Common Name:- Leaf Weevils
P_lfweevils Leaf weevils come in many different colours and shapes. They are slow moving beetles of a general shape. The larvae of which also eats the roots of the host usually in the winter. In UK, The green Leaf Weevil(Polydrusus impressifrons) is a common ...
Caused by:- Various Weevil Beetles
Control:- Spraying with a knock down insecticide will control these pest, but...

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Common Name:- Leafy Gall
P_leafygall Leafy gall is a bacterial disease of the stems and roots of many herbaceous plants. It is caused by the bacterium Rhodococcus fascians(formerly Corynebacterium fascians), which enters the plant through wounds in roots or stems and stimulates the p...
Caused by:- The Bacteria Rhodococcus fascians
Control:- The disease is not common and seldom severely damaging to warrant c...

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Common Name:- Leapord Moth
P_leapardmoth The Leopard Moth Zeuzera pyrina is a beautiful moth with two sets of three nearly parallel black stripes on its head and black spots on its wing. This moth larvae bores into the wood of a wide range of trees. There is also a Giant leapord moth(Hy...
Caused by:- The Larvae of Zeuzera pyrina
Control:- Spraying in late spring and early summer should kill the adults and...

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Common Name:- Leatherjackets
P_learherjkts One of the grubs of the Tepulidae species. Picture by Canadian Forest Service Archive, Canadian Forest Service, Bugwood.org.
Leatherjackets are the larvae of the Crane fly(Tipula simplex) and Nephrotoma species. The Crane fly has many common...
Caused by:- The Larvae of Tipula and Nephrotoma species
Control:- Encourage insect-eating birds by hanging feeders in the winter mont...

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Common Name:- Leek Moth
P_leekmoth The leek moth, Acrolepiopsis assectella (Lepidoptera: Acrolepiidae) is a local pest in Britain, being mainly found along the east and south coast of England, but as the temperatures are getting hotter it is moving inland. the larvae of this specie...
Caused by:- The larvae of Acrolepiopsis assectella
Control:- Examine the foliage of Alliums, and if you spot damage you can usua...

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Common Name:- Leek Rust
P_leekrust Leek Rust is a common disease of leeks in most seasons. It rarely causes much damage but severe infections may cause leaves to shrivel prematurely and will reduce vigour of the plants. Infections are clearly visible on leaves where bright orange p...
Caused by:- The Fungus Puccinia allii
Control:- Spraying with an approved systemic fungicide at the first sign of l...

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Common Name:- Leek White Tip
P_leekwhitetip Leek White Tip disease is a fungal disease caused by Phytophthora porrii that can become prevalent after heavy rainfalls later in the summer. The first symptoms appear in July and the disease progressed through the harvesting period the following ...
Caused by:- The Fungus Phytophthora porrii
Control:- There are many fungicides that can control this fungus and early de...

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Common Name:- Lettuce Downy Mildew
P_lettdnymldew Downy mildew of lettuce is a serious disease caused by the fungus Bremia lactucae that occurs worldwide. The symptoms are yellow patches and a white mould on leaves. Under favourable conditions, a white cottony-like fungal growth that is indicativ...
Caused by:- The Fungus Bremia lactucae
Control:- Spraying with fungicides is usually ineffective as the disease is s...

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Common Name:- Lettuce Grey Mould
P_letgreymld Lettuce Grey mould is caused by the fungus Botrytis cinerea which is a very common, quick-spreading disease and its airborne spores are always present. B. cinerea is also a cause of damping off in seedlings. It thrives as a saprophyte (a micro-org...
Caused by:- The Fungus The Fungus Botrytis cinerea
Control:- Although there aren't any specific chemicals available to treat gre...

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Common Name:- Lettuce Root Aphids
P_lettrtaphid Te Lettuce Root Aphid(Pemphigus bursarius) on Cichorium intybus. Picture from Wikimedia Commons.
There are several types of Root Aphids specific to certain plants. Lucikily they are usually rare except in certain circumstances.
The L...
Caused by:- The Root Aphid Pemphigus bursarius L.
Control:- Applying insecticide to the soil should help to control the infecti...

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Common Name:- Lettuce Viruses
P_lettvirus There are several viruses that have historically been severe problems of lettuce growers through the world, although their incidence and severity vary widely. Most infections are transmitted by aphids and other sap sucking animals and infected see...
Caused by:- Various Viruses
Control:- There is little one can do about viruses apart from removing the so...

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Common Name:- Lilac Bacterial Blight
P_lilacbacbligth Lilac Bacterial Blight is caused by the bacterium Pseudomonas syringae pv. syringae. The disease is also commonly referred to as Shoot Blight and Blossom Blight. The disease starts as brown spots on stems and leaves of young shoots as they develop...
Caused by:- The Bacteria Pseudomonas syringae
Control:- Try to keep the plant as healthy as possible by applying compost mu...

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Common Name:- Lilac Leafminer
P_lilaclfmnr There are many types of leaf miners that feed between the tissues of leaves. Leafminers are insects can be beetles(Coleoptera), (flies(Diptera), sawflies(Hymenoptera) and moths(Lepidoptera). The precise pattern of the feeding tunnel between the u...
Caused by:- The Larvae of the moth Caloptilia syringella
Control:- The lilac leafminer is best controlled by simply removing the leave...

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Common Name:- Lily Beetle
P_lilybeetle The Scarlet Lily Beetle(Lilioceris lilii) and its larvae can reduce a lily plant to mare stems in a few days. The beetle became established in Surrey in 1939, Although it has been found in the UK many decades before, and it remained confined to so...
Caused by:- The Adult and Larvae of Lilioceris lilii
Control:- The Lily Beetle and their larvae are easily gotten rid of by sprayi...

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Common Name:- Lily Disease
P_lilydisease Lily Disease is caused by the grey mould (Botrytis elliptica). There are two related Botrytis that can be found on lilies at the same time. B.elliptica and B.cinerea, both attack the above ground plant parts. B.elliptica is the more destructive of...
Caused by:- The Grey Mould Botrytis Elliptica
Control:- Spraying with a fungicide will control this mould, but most importa...

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Common Name:- Lily Viruses
P_lilyvirx Viruses are an ultra small intracellular parasite that can only be seen under an electron microscope.They come in many shapes and sizes. [See Viruses]
They will invade a cell injecting its own RNA into the cell, hijack the cells DNA and cau...
Caused by:- Various Viruses
Control:- The best way to reduce viral infections is to have good gardening p...

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Common Name:- Lime Induced Chlorosis
Limeindchl Lime Induced Chlorosis is not a pest as such, but is a symptom that there is something wrong, usually with soil nutrients. This Chlorosis is caused by too much lime(calcium) in the soil especially where acidic soil loving plants are grown. It can ...
Caused by:- Too much Calcium in Growing Media
Control:- Adding well-rotted manure or compost to any soil will help prevent ...

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Common Name:- Lime Nail Gall Mite
P_lmnailglmite From late Spring to Summer red or yellow-green tubelar progections(galls) , up to 5mm are seen on the top surfaces of the leaves of Lime trees(Tilia × europaea (synonym T. × vulgaris)). These are caused by the mite Eriophyes tiliae which feed on...
Caused by:- The Mite Eriophyes tiliae
Control:- Apart from creating the galls this pest does not seem to affect the...

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Common Name:- Lupin Aphids
P_lupinapd Aphids on Lupin. Picture from Wikimedia Commons.
There are several types of aphids that are associated with Lupins. They may have different common names according to which country they are in. Some species, which not only attack Lupins, are...
Caused by:- Various Species of Aphids.
Control:- Spraying with both knock down or systemic insecticide is the quicke...

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M
Common Name:- Magnesium Deficiency
P_magndef The effects of manganese deficiency is not a pest as such, but is a symptom that there is something wrong, usually with soil nutrients. It can occur on trees and shrubs, as well as on many herbaceous plants. It can easily be mistaken for a virus o...
Caused by:- Insufficient Magnesium in soil.
Control:- Mg deficiency can be rectified in the short term by applying a foli...

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Common Name:- Mahona Rust
P_mahoniarst Mahonia Rust is caused by the fungus Cumminsiella mirabilissima and deep-red spots with dark centers throughout the year on the upper leaf of Mahonia species. On the undersides are powdery brown pustules. If left untreated it will spread tot he w...
Caused by:- The Fungus Cumminsiella mirabilissima
Control:- Once your plant has rust, it's best to treat them with a fungicide,...

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Common Name:- Manganese Deficiency
P_manganesedif Very difficult to diagnose since it resembles to iron deficiency. Chlorosis is most severe at the top of the plant. Yellowing of the leaves appears first near leaf margins and develops in a V-shaped pattern. Leaves then develop a tan or gray spots...
Caused by:- Too Alkaline Soil Conditions
Control:- Manganese sulphate fertilisers, along with chelated forms of these ...

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Common Name:- Mealy Cabbage Aphids
P_mealycabaph The Mealy Cabbage Aphids(Brevicoryne brassicae) is just one of over 500 different species of aphids some of which are specific to one or two species of plants.
There are even aphids which attack below ground and live on the roots. These roo...
Caused by:- The Aphid Species Brevicoryne brassicae
Control:- Products containing the following chemical:- Bifenthrin, Imidaclopr...

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Common Name:- Mealy Plum Aphids
P_mealyplmaph Mealy plum aphid Hyalopterus pruni is just one of over 500 different species of aphids some of which are specific to one type of plants. Mealy plum aphid eggs overwinter on Prunus species, mainly plums, but also peaches, apricots and almonds. The...
Caused by:- The Aphid Species Hyalopterus pruni
Control:- Products containing the following chemical:- Bifenthrin, Imidaclopr...

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Common Name:- Mealybugs
P_mealybugs1 There are several species of mealybug which belong to the Pseudococcus or Planococcus Genus . Most thrive in warm conditions, which is why they are not usually seen on outdoor plants in the UK.
They are active all year round on houseplants ...
Caused by:- Pseudococcus or Planococcus species of insects
Control:- Spraying with an insecticide often does not work as their waxy coat...

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Common Name:- Melon Cotton Aphids
P_melcottaph The Melon Cotton Aphid(Aphis gossypii) is an important pest of cotton and is also called the cotton aphid or Melon Aphid and is one of the smaller aphids about 1.5mm.
It is just one of over 500 different species of aphids some of which are ...
Caused by:- The species of Aphids Aphis gossypii
Control:- Products containing the following chemical:- Bifenthrin, Imidaclopr...

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Common Name:- Meripilus Giganteus
P_meripilusgig Meripilus giganteus is a bracket fungus also known as the Giant polypore, Polyporus gigantea or Grifola giganteus. It is often found in large clumps at the base of trees, although fruiting bodies are sometimes found some distance away from the tru...
Caused by:- The Bracket fungus Meripilus giganteus
Control:- As this fungus only seem to attack mature trees an arborist or tree...

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Common Name:- Mice
P_mice There are several species of mice rodent that causes damage in the garden. Although the damage done in the garden is often unseen. They dig holes in pots to make nest in pots and in the greenhouse they scatter soil everywhere in the process of dig...
Caused by:- Several species of Rodent mice
Control:- There are several things that can be done to discourage them in you...

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Common Name:- Michaelmas Daisy Mites
P_mchdsymte Michaelmas Daisy Mite(Phytonemus pallidus), also known as the Cyclamen mite are cream to brown mites getting darker with age and about 0.25mm long long. They curl up into a saucer shape when disturbed, though you will need a powerful magnifying gl...
Caused by:- The Mite Phytonemus pallidus
Control:- Spraying with an insecticide which also kills mites will help contr...

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Common Name:- Michaelmas Daisy Wilt
P_michdsywlt Michaelmas daisy wilt is caused by the fungus Phialophora asteris and is soil borne. The first sign will be that leaves appear unnaturally pale, then turn yellow and brown from the base of the spray upwards. Eventually it will kill the whole plant...
Caused by:- The Fungus Phialophora asteris
Control:- If you spot it, the best solution is to remove and burn the entire ...

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Common Name:- Midges
P_midges There are hundreds of different types of midges. Some are unpleasant biting insects, but in relation to plants most Midges causes galls of one form or another. Often the midge larvae and sometimes adults lives inside the gall feeding on the plant....
Caused by:- Various Insects
Control:- Apart fron spraying with insecticides, many Midges can be repelled ...

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Common Name:- Millipedes
P_millipedes There are many Genera of Millipedes of the Phylum Arthropoda they have two pairs of legs per segment (except for the first segment behind the head which does not have any appendages at all, and the next few which only have one pair of legs). Each...
Caused by:- Various Arthropoda
Control:- Although most millipede species secrete repellent fluids, they are ...

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Common Name:- Mint Beetle
P_mintbtls The Mint Leaf Beetle(Chrysolina menthastri) is a pretty metallic green beetle that prefers waterside meadows and hedgerows. I can normally be found in the summer months munching away at the leaves of various mint plants. A little later in the summ...
Caused by:- The Beetle Chrysolina menthastri
Control:- If you grow cultivated mints for show then spraying at the right ti...

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Common Name:- Mint Rust
P_mintrust Mint rust is a common fungal disease of garden mint, which also affects other herbs like marjoram and savory. The fungus causes vivid dusty orange spores, which later fades to brownish/black resting spores, on the underside of the leaves. The top ...
Caused by:- The Fungus Puccinia menthae
Control:- Remove the infected plants along with its rhizomes as soon as the f...

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Common Name:- Mites
P_mites There are many species of mites which are small or minute(less than 1mm) arachnids of the order Acarina. Some are often parasitic on animals and plants, infest stored food products, and in some species transmit disease, whilst some are beneficial ...
Caused by:- Various Mites
Control:- There are various control measures that can be taken, but these mus...

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Common Name:- Moles
P_moles Moles(Talpa europaea) in the garden are not harmful as such, but they can wreck your garden by the tunnels and chambers they dig. They are attracted to gardens because of the earthworms and other insects that live beneath the soil but they are not...
Caused by:- The Animal Talpa europaea
Control:- There are many different methods of eradicating moles and methods i...

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Common Name:- Molybdenum Deficiency
P_molybdenum Molybdenum deficiency is very rare as it is a micro-nutrient and only needed in minute quantities. Nevertheless when it is deficient it causes problems in many plants especially Brassicas where it causes whiptail and citrus where it causes Yellow ...
Caused by:- Usually Acidic Soils
Control:- Foliar feeding with molybdenum salts is usually sufficient to satis...

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Common Name:- Moths
P_moths A moth is an insect closely related to the butterfly, both being of the order Lepidoptera and have a wingspan of between 5mm and 80mm. Although Moths and Butterflies are very similar, they have many differences. Most butterflies fly during the day...
Caused by:- Various species of Lepidoptera
Control:- Various detrimental moths and their larvae have specific control me...

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Common Name:- Mountain Ash Blister Mite
P_mnashblstmite The Mountain Ash Blister Mite is the same mite that causes pear Leaf Blister Mite(Phytoptus pyri previously Eriophyes Pyri). This mite is also causes problems on Apple, Pear, Quince, Hawthorn and Cotoneaster and other related species. The bodies o...
Caused by:- The Mite Phytoptus pyri(Eriophyes Pyri)
Control:- Spraying with a systemic insecticide or oils will help, but the mai...

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Common Name:- Mulberry Cankers
P_mulcanker The majority of canker-causing organisms are tied to a single host species or genus, but a few will attack a wider range of plants. This is the case with Mulberry Canker caused by Fusarium lateritium, which will attack many species such as apple, ...
Caused by:- Various Fungi and Bacteria
Control:- Canker and anthracnose are general terms for a large number of diff...

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Common Name:- Mulbery Bacterial Blight
P_mulbbacblght Mulberry Bacterial Blight(Pseudomonas syringae pv. mori) causes black or brown irregular spots on leaves, often with a yellow halo around the spot appears. As the infection progresses the entire leaf may become yellow wilt, turn brown and die. If...
Caused by:- The Bacteria Pseudomonas syringae pv.mori
Control:- Spraying does not reliably control bacterial blight and the best de...

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Common Name:- Mullien Moth
P_mulleinmth The Mullein Moth Cucullia verbasci is a Noctuid moth and is a pest of Mullein(Verbascum), Buddleia and Figwort at the end of spring. With this moth the seldom-seen adults fly in April to May. Their wings are dark brown and pointed, with scalloped ...
Caused by:- The Larvae of the moth Cucullia verbasci
Control:- Spraying at the right time in the Spring will kill the caterpillars...

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Common Name:- Mushrooms
P_toadstool Mushrooms or Toadstools is caused by fungi and can develop all over the garden, wherever there is organic matter for it to decay. It is a natural part of the flora of any garden and most toadstools fungi are providing a useful service in recycling...
Caused by:- Various Fungi
Control:- Simply brush off the toadstools when they appear, to prevent them f...

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Common Name:- Mussel Scale
P_musselsc Mussel scale(Lepidosaphces Ulmi) is also known as the oystershell scale, but in New Zealand the name Oystershell scale is reserved for Quadraspidiotus ostreaeformis. It has a shape that resembles a saltwater mussel.
It is found on twigs at ...
Caused by:- The Scale insect Lepidosaphces Ulmi
Control:- Spraying with an insecticide in early spring when the crawlers are ...

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Common Name:- Mycoplasma Infections
P_mycoplasma Mycoplasma is a genus of bacteria that lack a cell wall and the smallest known free-living life forms. They are capable of replication and cause various diseases in humans, animals, and plants. In humans diseases like Pneumonia are caused and in p...
Caused by:- Various Mycoplasma
Control:- At the moment there are no known cure and removal of the infected p...

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N
Common Name:- Narcissus Bulb Fly
P_narcisblbfly There are three species of narcissus fly Merodon equestris, Eumerus strigatus and E. tuberculatus. However, it is the large narcissus fly Merodon equestris which causes the most problems as it can attack healthy bulbs, whereas the other two only ...
Caused by:- Three Species of fly.
Control:- If the bulbs are to remain in the soil remove the leaves as soon as...

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Common Name:- Narcissus Eelworm
P_narcissuseelworm1 Narcissus eelworm are also responsible for damage to bulbs and corms of Tulips and Hyacinths, Bluebells, Snowdrops, onions and other plants like beans and peas. The Narcissus Eelworm or Nematode (Ditylenchus dipsaci) is invisible to the human eye....
Caused by:- Microspic nematodes Ditylenchus dipsaci
Control:- If eelworm is discovered, dig out and destroy affected bulbs and an...

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Common Name:- Narcissus Leaf Scorch
P_narcislfsch Narcissus leaf scorch caused by Stagonospora Curtisii and is very common in south-west England. This fungus also attacks Amaryllis as well as Narcissus species and some related genera. Early symptoms of the disease is that the leaf tips become red...
Caused by:- The Fungus Stagonospora Curtisii
Control:- No certain control measures can be recommended, but fungicides appl...

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Common Name:- Narcissus Leaf Scorch
P_narcissmldr Narcissus Smoulder is caused by Sclerotinia (Botrytis) narcissicola and is a widespread foliar disease of Narcissus cultivars. It causes significant losses in bulb and flower yield. This fungus infects immature, dying or damaged foliage, flower p...
Caused by:- The Fungus Sclerotinia (Botrytis) narcissicola
Control:- Spraying around and after flowering will control secondary smoulder...

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Common Name:- Nectria canker
P_nectriacanker This fungal species(syn. Nectria galligena) is a frequent cause of cankers in apple, pear, beech and other trees. It produces cankers in the wood of branches and trunks and severe attacks can result in the loss of a branch or the death of the tree...
Caused by:- The Fungus Neonectria galligena
Control:- Eradication of this fungi is almost impossible as the spores are al...

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Common Name:- Needle Blight of Conifers
P_needlebltcon There are several fungi that causes Needle Blight of conifers by girdling and killing the needles and branch tips. Blights can cause major commercial and ornamental damage to conifers. Infected needles often fall from the tree, usually in the year...
Caused by:- Various Fungi
Control:- Cutting out affected areas will help to control these diseases, but...

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Common Name:- Nematodes
P_chrysanteelworm The nematodes are a very successful group of animals that have colonised every possible living ecosystem from marine to fresh water, from the polar regions to the tropics, as well as the highest to the lowest of elevations. They are important par...
Caused by:- Various worms
Control:- See specific nematode control like Eelworms, Enchytraeid worms, Lea...

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Common Name:- Nitrogen Deficiency
P_nitrogendif The effects of nitrogen deficiency is not a pest as such, but is a symptom that there is something wrong, usually with soil nutrients. All plants with perhaps the exception of nitrogen fixing legumes are prone to nitrogen deficiency. Symptoms incl...
Caused by:- Lack of Available NItrogen
Control:- Prevention and control of nitrogen deficiency can be achieved in th...

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Common Name:- Nut Weevil
P_nutwvil There are several beetles of the Curculionidae family that predates various nuts. The Nut weevil (Curculio nucum) can be very serious pests of native and non-native nut trees like Hazelnut. These damaging insects begin to attack the kernels in the...
Caused by:- Several species from the family Curculionidae
Control:- Weevils usually move only a short distance after emerging and often...

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O
Common Name:- Oak Gall Wasps
P_oakglwsp There are about 1000 different species of gall forming wasps that inhabit Oak(Quercus species). Some forming the galls known as Oak apple, Oak Marble gall, Knopper gall, Rose bedeguar gall, horned oak gall wasp, and the Common Spangle gall. The la...
Caused by:- Various Wasps.
Control:- In general, most leaf galls on do not affect the health of the host...

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Common Name:- Oak Phylloxera
P_oakphylxera The Oak Phylloxera is a small yellowish sap sucking, aphid like insect about 1mm long of the Phylloxera genus some of which causes galls where the insect resides. There are approximately 12 species in this genus which attack specific trees or vine...
Caused by:- Insects of the Phylloxera genus
Control:- Is not normally considered as mature trees are apparently not serio...

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Common Name:- Oak Powdery Mildew
P_oakpwdrymldw Powdery mildews are one of the most widespread plant diseases. They affect virtually all kinds of plants from cereals and grasses, to fruit trees, and broad-leaved shade trees.
Powdery Mildew of oak is caused by the fungus Erysiphe alphitoi...
Caused by:- The Fungus Erysiphe alphitoides
Control:- The major factors that are believed to influence the spreading of t...

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Common Name:- Oats Halo Blight
P_oatshaloblight Halo blight is a common bacterial disease of oats and appears early in the season, usually earlier than any of the diseases caused by fungi and other bacteria. This is because the first shoots are infected by bacteria on the surface of the seeds....
Caused by:- The Bacteria Pseudomonas coronafaciens
Control:- This bacteria disease is seedborne and can survive on infected crop...

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Common Name:- Oedema
P_odema Oedema is not a disease as such, but occurs when roots take up water faster than it can be used by the plant or transpired through the leaves. Water pressure then builds up in the internal cells of the leaf or flower petals causing them to enlarge...
Caused by:- Too Much Water
Control:- Improve air circulation by spacing plants farther apart and increas...

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Common Name:- Oleander Scale Insect
P_olnderscle There are hundreds of scale insects. Some are specific to certain plants and others are host unspecific.
Scale insect is a nasty little sap sucking insect, that like barnacles on a hull, latch onto your plant and suck the sap and weaken the...
Caused by:- The Scale insect Aspidiotus nerii
Control:- Scraping off the scales if there are a few will control the infesta...

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Common Name:- Onion Downy Mildew
P_oniondnmldw Onion Downy Mildew affects the onion-family of plants, including garlic and ornamental species. It is caused by the fungus Peronospora destructor that overwinters on infected plants debris and can remain in the soil for at least five years. It is ...
Caused by:- The Fungus Peronospora destructor
Control:- Good hygiene is the first line of defence. Always remove all plant ...

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Common Name:- Onion Eelworm
P_onionelwrm Onion Eelworms(Ditylenchus dipsaci) are microscopic worms that live in the soil and infects onion family of plants. This eelworm can also infect Narcissus, carrots, peas, potatoes, strawberry, alfalfa, oats, clover and probably man more plants and...
Caused by:- The Nematode Ditylenchus dipsaci
Control:- Apparently planting mustard as a green manure is supposed to produc...

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Common Name:- Onion Fly
P_onionfly1 The onion fly (Delia antiqua), which almost looks like a normal house fly, attacks shallots, leeks, garlic and all members of the Allium genus. They overwinter as pupae in the soil and emerge in April/May to lays its eggs, which are white elongate...
Caused by:- Delia antiqua
Control:- This fly is attracted to the smell of onions therefore anything tha...

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Common Name:- Onion Neck Rot
P_onionnkrot There are at least seven Botrytis species that affects Onion and other Allium species Three species B. allii, B. squamosa and B. cinerea causes neck rot, but the most serious of these species causing neck rot is B. allii. THE Onions appear health...
Caused by:- Botrytis Species
Control:- Fungicide applications during the season and especially prior to ha...

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Common Name:- Onion Thrips
P_onionthrips Onion thrips (Thrips tabaci) is a world wide pest of onions, other Allium species and several crops, such as cabbage, cotton, celery, tomatoes, beans, cucumber and pineapple. Thrips are easily detected by visual inspection of the onion plant as th...
Caused by:- The insect Thrips tabaci
Control:- There are several natural enemies that help in the control of thrip...

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Common Name:- Onion White Rot
P_onionwhtrot Onion White Rot is a serious fungal disease of Allium species caused by Sclerotium cepivorum. It is soil bourn by the sclerotia(resting spores), which can remain in the soil for up to 15 years The fungus grows on the roots of the plant, causing t...
Caused by:- The Fungus Sclerotium cepivorum
Control:- Burn or destroy infected plants as soon as possible.<br /> There a...

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Common Name:- Orchid Viruses
P_orchdvrus Viruses in orchids are probably worse than bacterial or fungal infections as when the orchid is infected there is no cure and the plant should be destroyed. There are many viruses that can infect orchids, but three are most common and virulent an...
Caused by:- Various viruses
Control:- Always sterilise tools after using on orchids if it is suspected of...

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Common Name:- Oribated Mites
P_oribatedmts Oribatid Mites are a group of mites which live in the soil in cracks and holes made by other animals and in the bark of trees. They are tiny about 1mm long. Their colour can vary and like all mites are closely related of ticks and spiders. These ...
Caused by:- Various mites
Control:- No control is necessary as these mites do not feed on the tree or p...

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P
Common Name:- Pansy Downy Mildew
P_pansydwmldw Downy mildew of pansies is a fungal-like disease caused by Peronospora violae(Bremiella megasperma). It causes pale blotches on the upper surfaces of the leaves and fuzzy grey mould growth on the underside of leaves. Eventually the whole leaf die...
Caused by:- The fungal-like organism Peronospora violae
Control:- Remove infected leaves as soon as the discolouration on the upper s...

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Common Name:- Pansy Leaf Spot
P_pansylfspt Pansy Leaf Spot is caused by several fungi including Centrospora violae, Ramularia deflectens, and Phyllosticta minima Alternaria violae. These fungi are especially rampant when the weather is cold, wet, and windy or when seedbeds are crowded an...
Caused by:- Various Fungi
Control:- Spray with systemic insecticides, but fungicides can reduce infecti...

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Common Name:- Pansy Powdery Mildew
P_pansypwdmldw Powdery mildews are one of the most widespread plant diseases. They affect virtually all kinds of plants from cereals and grasses, to fruit trees, and broad-leaved shade trees.
Pansy Powdery mildew is a fungal disease that is particularly p...
Caused by:- Various Fungi
Control:- Powdery mildew does not like wet conditions, it is worst when the w...

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Common Name:- Pansy Sickness or Stem Rot
P_pansyskness Pansy Sickness is also called Stem Rot and is caused by the soil-borne fungus Pythium violae. The symptoms are difficult to catch early as it starts at the base of the plant near the soil where the tissues becomes watersoaked and soggy. The plant ...
Caused by:- The Fungus Phytium violae
Control:- It is important to remove infected plants as soon as possible and d...

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Common Name:- Papery Bark Disease
P_paperybk Two diseases are often called Papery Bark which attacks many apple and stone fruit trees. One is also called Sappy bark and is caused by the fungus Trametes versicolor. This mainly affects older branches and is introduced by wounds to the bark or ...
Caused by:- The FungusTrametes versicolor
Control:- In both cases trees should be invigorated by ensuring good drainage...

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Common Name:- Parsnip Canker
P_psnipcnkr Parsnip Canker can be a serious disease of parsnips especially in wet soils. It is caused mainly by the fungus Intersonilia pastinaceae, though other fungi, like Phoma and Mycocentrospora, can cause this disease. It causes the storage root to dark...
Caused by:- Various Fungi
Control:- Prompt removal and disposal by burning of debris from infected sour...

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Common Name:- Parsnip Viruses
P_parsnipvirus There are several viruses that infect Parsnips, but two Parsnip yellow fleck virus (PYFV) and Parsnip mottle virus (PMV) are most prevalent. The symptoms are yellow markings on the leaves often as bands on the leaves or a mottling or mosaic patter...
Caused by:- Various Viruses
Control:- Promptly remove any infected plants and burn, as feeding insects on...

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Common Name:- Pea and Bean Weevil
P_pandbeanweevil Sitona lineatus feed on peas vetch, lentil, and beans in gardens but is usually a minor pest causing little damage to the crop, but in some countries it can be a major pest. As an adult, this Weevil feeds on the leaves of many leguminous species...
Caused by:- The Weevil Sitona lineatus
Control:- Spraying with a knock down insecticide and also soaking the soil wi...

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Common Name:- Pea Downy Mildew
P_peadnymldew Pea Downy mildew is caused by the fungus-like plant pathogen Peronospora viciae which is worldwide in distribution. It is a fungus-like microorganism which overwinters on diseased plant debris in soil and is most severe on young plants.
The...
Caused by:- The Fungus-Like Peronospora viciae
Control:- Good hygiene is the first line of defence. Always remove all plant ...

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Common Name:- Pea Leaf and Pod Spot
P_pealfpodspot Peas can suffer from such a wide range of diseases it is a wonder it is usually an easy crop to grow. some of the diseases that affect peas are:-
Bacterial diseases
Bacterial blight, Brown spot
Fungal Diseases
Alternari...
Caused by:- Various Fungi usually Ascochyta
Control:- This diseaseis agravated by wet conditions and is also carried over...

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Common Name:- Pea Marsh Spot
P_peamarshspot Circular brown areas develop in the center of the seeds or cotyledons, which later forms a cavity. The peas are spoilt for consumptionand sale.
The cause is a lack of manganese. This is most prevelant where there is a high organic content, ...
Caused by:- Manganese Deficiency
Control:- Foilar feeding with a fertiliser which contains manganese and impro...

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Common Name:- Pea Moth
P_peamoth The pea moth Cydia nigricana, attack field and garden peas along with sweet peas and vetch. It is about 6mm long with a 12mm wingspan. It is brown in colour with black and white bars on the front edge of its forewings and antennae. They emerge fr...
Caused by:- The Moth Cydia nigricana
Control:- Planting early and don’t delay harvesting or late planting will mis...

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Common Name:- Pea Powdery Mildew
P_peapowmildw Powdery mildews are one of the most widespread plant diseases. They affect virtually all kinds of plants from cereals and grasses, to fruit trees, and broad-leaved shade trees.
The fungus “Erysiphe pisi” causes powdery mildew of peas and be...
Caused by:- The Fungus Erysiphe pisi
Control:- Attacks of powdery mildew start in dry seasons and are worst in she...

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Common Name:- Pea Thrips
P_peathrips There are over 6,000 species of thrips known around the world, with over 300 of these in Europe and about 150 native to Britain. Pea thrips Kakothrips pisivorus, also known as thunderflies as they often take to the air in large numbers in thundery...
Caused by:- The insect Kakothrips pisivorus
Control:- Activity peaks in hot dry conditions when a careful watch is needed...

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Common Name:- Pea Viruses
P_peaviruses Peas are susceptible to a large number of viruses which are usually transmitted by aphids. Many of these viruses can occur singularly or in combination.
Viruses infecting peas belong to three distinct virus groups. Pea Enation Mosaic is the...
Caused by:- Several Viruses
Control:- Once infected there is no cure for viruses. As most viruses are tra...

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Common Name:- Pea Wilt
P_peawilt Peas Wilt diseases is caused by the fungus Fusarium oxysporum f. sp. pisi. Several races of the fungus occur and may cause different symptoms. Typically, plants are yellow, stunted, wilted, and often die. Plants may also show a yellowish to orange...
Caused by:- The Fungus Fusarium oxysporum f. sp. pisi
Control:- Growing resistant varieties are probably the only defence to this f...

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Common Name:- Peach Aphids
P_peachaphid Peach aphid Brachycaudus schwartzi attacks Peaches, Nectarines Almonds and other related plants.
It is a transmitter of viruses and other diseases and should be treated as soon as possible.
The leaves many become yellowish/green curl...
Caused by:- The aphid Brachycaudus schwartzi
Control:- From Spring onwards a lookout for aphids on peach trees is needed a...

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Common Name:- Peach Leaf Curl
P_peachleafcurl1 Peach leaf curl is one of those hard to avoid and yet is preventable diseases of peaches, almonds, nectarines, apricots and ornamental Prunus. The infection is carried in the air and gets in the flower and leaf scales over the winter and when the ...
Caused by:- The Fungus Taphrina deformans
Control:- One of the best ways to avoid this fungus is to arrange a cover to ...

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Common Name:- Pear and Apple Canker
P_nectriacanker2 Areas of the bark sinks inwards. It is most often associated with a wound or bud. The bark changes colour and shrinks and cracks forming concentric rings of bark which easily peels off. As the fungus grows around the stems the upper branches and l...
Caused by:- The Fungus Nectria galligena
Control:- This fungus spreads mainly by wind blowing the spores in spring. Th...

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Common Name:- Pear and Cherry Slugworm
P_pandcslugworm The Pear and Cherry Slugworm (Caliroa cerasi) attacks Hawthorne, mountain Ash, Plums, Sorbus and Quince. It is actually a bottle green insect larvae, of a sawfly, which covers its body in a black slimy mucilage which makes it look like a slimy sl...
Caused by:- The Sawfly larvae of Caliroa cerasi
Control:- Spray with a contact insecticidal spray such as soon as they are no...

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Common Name:- Pear Bedstraw Aphid
P_pbedstrawaphid Pear-bedstraw aphid (Dysaphis pyri) is a large, pinkish-brown aphid with a mealy waxy coating and is the commonest aphid on pears. It attacks the young shoots and causes the leaves curl and discolour due to the honeydew produced by their excretion...
Caused by:- The Aphid Dysaphis pyri
Control:- There are many ways to eradicate aphids. Spray with insecticide, bo...

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Common Name:- Pear Boron Deficiency
P_pborondif Pear Boron-deficiency can cause pitting and distortion on the fruit surface, but also causes patches of dead brown cells inside the fruits which affects the texture and taste. Some varieties are more prone to this problem. See also other problems ...
Caused by:- Too much Lime on Sandy soil.
Control:- The cause of Boron Deficiency can be too much lime and or drought c...

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Common Name:- Pear Juniper Rust
P_pearjnprst Pear Juniper Rust is caused by the rust fungus Gymnosporangium sabinae(G. fuscum). Like most rust diseases it requires two different host to complete its life cycle from year to year. With this fungus juniper is the winter host and pear is summer...
Caused by:- The Fungus Gymnosporangium sabinae
Control:- It is important to break the disease cycle and remove infected leav...

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Common Name:- Pear Leaf Blister Mite
P_pearlfblstmte Fallen leaves of vine maple (Acer circinatum) showing damage by Pear leaf Blister Mites.
The Pear-Leaf Blister Mite(Phytoptus pyri previously Eriophyes Pyri) is the same mite that causes Blister Mite in other plantslike Apple, Pear, Quince...
Caused by:- The Mite Phytoptus pyri(Eriophyes Pyri)
Control:- Spraying with a systemic insecticide or oils will help, but the mai...

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Common Name:- Pear Midge
P_pmidge Pear Midge is a tiny fly (Contarina pyrivora), the larvae of which damage immature pears. This pest is widespread and can be quite damaging to the crop. The adult is only 2.5-4mm long and darkly coloured and emerge from the soil in April and May, ...
Caused by:- The insect larvae of Contarina pyrivora
Control:- There is not much you can do once an outbreak has occurred, but pic...

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Common Name:- Pear Scab
P_pscab Pear scab is most prevalent in mild, damp seasons. It is caused by the fungus Ventura pirina which is closely related to the apple scab fungus Venturia inaequalis. The fungus overwinters on fallen leaves in the form of spores, which can be splashe...
Caused by:- The fungus Ventura pirina
Control:- Good husbandry is essential in preventing this disease. Therefore r...

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Common Name:- Pear Stony Pit Virus
P_pspvirus Stony pit causes deformity and pitting of pear fruits and is caused by a virus. Symptoms begin as early as three weeks after petal fall, when dark green spots form on the fruit. Areas surrounding these spots continue to grow while spots stop, resu...
Caused by:- A virus
Control:- Some varieties are more prone to this virus and as with any virus o...

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Common Name:- Pear Sucker
P_pearsucker Pear sucker (Psylla pyricola) also called Pear Psylla can be a major pest for orchards, but is less common in gardens. The nymphs appears in the spring on developing leaf and blossom trusses later in the summer they move to the leaves. Where the p...
Caused by:- The Sucking Insect Psylla pyricola
Control:- Encouraging their natural preditors like beetles and lacewings shou...

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Common Name:- Pedicil Necrosis
P_pednecrosis Pedicel Necrosis or Infloresent Necrosis is where the flower buds develop normally then suddenly droop and die. The pedicel behind the bud discolours and dies. Some grapevines are prone to this problem. So far no link has been found with any virus...
Caused by:- Physicological Probably Too much Nitrogen
Control:- Feed the plants with potassiun in the spring and autumn. Avoid too ...

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Common Name:- Pelargonium Rust
P_pelargoniumrust1 This fungus is specific too Zonal Pelargoniums Ivy-leaved pelargoniums are not affected. It produce dark brown, fungal pustules on the underside of the leaves. They are arranged in concentric circles and there is a yellowing of the leaves above th...
Caused by:- The Fungus Puccinia pelargonii-zonalis
Control:- The spores germinates and infect best when the temperature is betwe...

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Common Name:- Pelargonium Viruses
P_pelviruses There are many viruses that can attack Pelargoniums, which are often called Geraniums, Some are more specific to Pelargoniums like Pelargonium line pattern virus (PLPV) or Pelargonium zonate spot virus (PZSV) and some are more catholic in their h...
Caused by:- Several Viruses
Control:- Once the symptoms appear there is no cure with viruses and removing...

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Common Name:- Peony Leaf Blotch
P_peonylfblotch Peony leaf blotch is caused by the fungus Cladosporium chlorocephalum (formerly Cladosporium paeoniae). It has also been called measles or stem spot. The infections on young stems first appear as elongated, reddish-brown streaks. As growth contin...
Caused by:- The Fungus Cladosporium chlorocephalum
Control:- Good husbandry is essential in eradicating this disease and stems s...

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Common Name:- Peony Wilt
P_peonywilt Peony wilt is a fungal infection by Botrytis paeoniae, which attacks the leaves and stems of peonies, including tree peonies, causing the foliage to collapse and flowers die before opening. The basal parts of the flower stalk, which are wilting, l...
Caused by:- The fungus Botrytis paeoniae
Control:- Spraying with fungicides will help, but is not always effective. Th...

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Common Name:- Periwinkle Rust
P_periwklerust Periwinkle rust is caused by the fungus Puccinia vincae. It causes numerous raised chocolate brown pustules primarily on the underside of the host's leaves. Infected plants often fail to produce flowers, develop an erect habit and may become disto...
Caused by:- The Fungus Puccinia vincae
Control:- Because this fungus invades the roots fungicidal control is not rec...

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Common Name:- Pestalotiopsis Leaf Spot
P_petotpsis Pestalotiopsis is a genus of fungi that causes leaf and stem necrosis in many plants from palms to shrubs. The symptoms vary with the particular specie. It attacks foliage that has been injured or weakened by unfavourable weather or growing condit...
Caused by:- Several Fungi of the Genus Pestalotiopsis
Control:- Prune damaged foliage and twigs as soon as possible in the spring. ...

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Common Name:- Petal Base Holes
P_petalbsehle Holes at the base of the petals of some flowers are usually caused by bees and a few insects trying to get to the flower nectar. This often happens in plants like beans where the nectar is more difficult to obtain. Once a hole is made other insect...
Caused by:- Bees and Insects
Control:- This problem is usually of very minor incidence and can be ignored ...

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Common Name:- Petunia Foot Rot
P_petrtrot Petunia root rot can be a devastating fungal disease of petunias. It is caused by the fungus Phytophrhora ccryptogea which lives in contaminated soils as resting spores. The fungus causes a blackening of the lower parts of the plant and the roots....
Caused by:- The Fungus Phytophthora cryptogea
Control:- Once the infection takes a hold the best practice is uprooting the ...

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Common Name:- Petunia VIruses
P_petvirus There are over 100 viruses that can attack Petunias. The symptoms they cause will be the only way to identify them. Some will have no visual symptoms, but cause a decline in its growth and others will cause yellow flecking, spotting, mosiacing and...
Caused by:- Several viruses
Control:- There is nothing that can be done once the virus has established it...

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Common Name:- Phellinus ignarius
P_phellinusig Phellinus ignarius is a polypore bracket fungus that often attacks birch, alder or willow trees The fruiting body has a brown cap growing at the edges. The pores are about 2.5cm ling and can be stacked on top of each other. This mushroom is grown ...
Caused by:- The Polypore Fungus Phellinus ignarius
Control:- There is no cure for this fungus because the mycelium is inside the...

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Common Name:- Phellinus Pomaceous
P_phellinusfm There are several species of Fomes fungi(Phellinus pomaceous) which attack a variety of trees. from Apple to Pine trees, and causing fungal fruiting bodies to appear on the ...
Caused by:- The Fungus Phellinus pomaceous(Fomes pomaceous)
Control:- There is little that can be done except pruning out the infected br...

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Common Name:- Phlox Eelworm
P_phloxeelwrm The Phlox eelworm Ditylenchus dipsaci is thankfully, quite rare. It is, like most eelworms, microscopic and lives in the stems of the phlox. And overwinters in the buds at soil level. It does not enter the roots therefore root cuttings will be fre...
Caused by:- The Nematode Ditylenchus dipsaci
Control:- Usually the only remedy is to plant something else in the spot, but...

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Common Name:- Phlox Powdery Mildew
P_phloxpmldw Powdery mildews are one of the most widespread plant diseases. They affect virtually all kinds of plants from cereals and grasses, to fruit trees, and broad-leaved shade trees.
The fungi that causes Powdery Mildew on Phlox is Erysiphe cicho...
Caused by:- The fungi Erysiphe cichoracearum and Sphaerotheca fuliginea
Control:- Maintaining good air circulation will help reduce powdery mildew pr...

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Common Name:- Phomopsis Canker
P_phomopsiscnkr Phomopsis Canker is caused by several species of the Phacidiopycnis (Phomopsis) fungus. It attacks a range of plants including Pines, Conifers, American and European Cranberries, Blueberry. Some species of Phomopsis are notifiable diseases in cert...
Caused by:- Several species of Phacidiopycnis (Phomopsis) Fungi
Control:- Spraying is not very effective, but a winter tar or oil wash may li...

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Common Name:- Phormium Mealybug
P_phoriummbug The Phormium mealybug or New Zealand Flax Mealybug Balanococcus(Trionymus) diminutus (formally Pseudococcus diminutus) is a small soft bodied insect that inhabits the tight confines of the leaf base of New Zealand Flax(Phormium Tenax). It is abou...
Caused by:- The insect Balanococcus(Trionymus) diminutus
Control:- The best control for this insect is removal of infected plant parts...

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Common Name:- Phosphorus Deficiency
P_phospdef Phosphorus(P) is one of the three main chemicals along with Nitrogen(N) and Potassium(K) in fertilisers(NPK) that is needed in any plant with a few exceptions like Proteas which do not tolerate high levels in the soil. Phosphorus deficiency in pla...
Caused by:- Various causes
Control:- It can be controlled by applying bone meal or superphosphate to rem...

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Common Name:- Phytophthora
P_phytophthora Phytophthora is a genus of soil-borne fungi which cause root rot of herbaceous and woody plants. Some of them cause Damping Off Disease and P. infestans is an oomycete or water mold that has been around for over 150 years causing potato and tomato...
Caused by:- Several species Of The Fungi Phytophthora
Control:- There are no treatments to clear up infected plants so they should ...

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Common Name:- Phytotoxicity
P_phytxcty Phytotoxicity is a term used to describe the degree a chemical is toxic, harmful or lethal to plants i.e. plant poisoning. This picture shows phytotoxicity due to a certain fungicide. Such damage may be caused by a wide variety of compounds, inclu...
Caused by:- Various causes
Control:- There are several ways to reduce the chances of phytotoxicity. Gard...

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Common Name:- Pierce Disease
P_piercedis Pierce's disease is caused by the bacterium Xylella fastidiosa that tends to live in the xylem of grapevines where it produces a gel which prevents nutrients transport. Leaves on vines with Pierce's disease will turn yellow and brown, and eventual...
Caused by:- The bacterium Xylella fastidiosa
Control:- If caught early enough the infected branch could be pruned below th...

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Common Name:- Pigeons
P_pigeons Pigeons Columba oenas is the type species of the family of doves and pigeons Columbidae. It is a very useful and helpful bird to mankind. It has been used in war to transmit messages, in helping search and rescue, as an ornamental bird bred for t...
Caused by:- The Bird Columba palumbus
Control:- The best way to avoid pigeon damage is to net the crops or fruits a...

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Common Name:- Pinapple Gall Adelgid
P_pnplegladelgid Most spruce trees are attacked by one of two species of gall forming adelgids, which are related to aphids. The pineapple or pseudocone gall adelgid Adelges abietis and the Cooley spruce gall adelgid Adelges cooleyi both of which feeds on the pla...
Caused by:- Two Species of adelgids
Control:- Although the old galls can be unsightly this pest has little lastin...

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Common Name:- Pine Adelgid
P_pineadelgid The Pine Adelgid Pineus pini(Chermes pini) is aphid-like insects in the family Adelgidae that primarily feeds on pines(Pinus), Spruce(Picea), Larch(Larix) and Silver Fir(Abies). It is closely related to the Pine Bark Adelgid Pineus strobi. They fe...
Caused by:- The Adelgid Pineus pini
Control:- There is usually no need for spraying as there are plenty of predat...

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Common Name:- Pine Bark Adelgid
P_pinebarkadel The Pine Bark Adelgid Pineus strobi is aphid-like insects in the family Adelgidae that primarily feeds on pines(Pinus), Spruce(Picea), Larch(Larix) and Silver Fir(Abies). It is closely related to the Pine Adelgid Pineus pini.
The immature a...
Caused by:- The Adelgid Pineus strobi
Control:- There is usually no need for spraying as there are plenty of predat...

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Common Name:- Pine Needle Blight and Casts
P_pinenbltcst Pine Needle Blight and Casts can affect all pines. Needle cast fungi often are quite host-specific and can be an indication of the fungus involved. These diseases are caused by several fungi some of which are Bifusella linearis, Cyclaneusma minus,...
Caused by:- Several Fungi
Control:- Control of needle cast in urban forest trees is usually not necessa...

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Common Name:- Plane Anthracnose
P_plnantnose Symptoms of the fungal plant pathogen Apiognomonia veneta on the leaf of a Platanus occidentalis tree. Picture from Wikimedia Commons.
Plane anthracnose caused by the fungus Apiognomonia veneta(Gnomonia platani) is more commonly known as Sy...
Caused by:- The Fungus Apiognomonia veneta(Gnomonia platani)
Control:- Plane and sycamore trees should be planted where they receive good ...

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Common Name:- Plum Blossom Wilt
P_plmbloswlt Plum Blossom Wilt is a fungal disease, which also affects apples, pears, plums, cherries and related ornamental trees. It kills blossoms, spurs and small branches. The problem is caused by two Sclerotinia species of fungi S. laxa (Monilinia cinere...
Caused by:- Two Species of Sclerotinia Fungi.
Control:- Spraying operations can only be effective when they kill the spores...

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Common Name:- Plum Fruit Moth
P_plmftmoth The Plum Fruit Moth Cydia (Grapholita) funebrana is as serious a pest of plums and Prunus species. The moths appear during April and May, flying mostly in the evenings (before sunset) around plum trees and laying one, occasionally two eggs on the ...
Caused by:- The Moth Cydia (Grapholita) funebrana
Control:- On isolated trees a pheromone plum moth trap can be used between Ma...

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Common Name:- Plum Gall Mite
P_plmgllmte Plum Leaf Gall mites(Phytoptus similis (Nalepa)) are microscopic members of the arachnid class(mites, spiders, false scorpions, harvestmen etc.) and the Eriophyidae family(Gall mites). They attack a wide range of fruit and ornamental garden plants...
Caused by:- The MIte
Control:- Spraying in the spring with fungicides should stop the attack, but ...

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Common Name:- Plum Leaf-Curl Aphid
P_plmlfcrlaphd Plum Leaf-Curling Aphids Brachycaudus helichrysi occurs on various Prunus species in large colonies on young shoots and the undersides of leaves. They suck the sap from the leaves which causes the leaves to become tightly curled, crumpled and dist...
Caused by:- The Aphid Brachycaudus helichrysi
Control:- Several natural enemies, like ladybird beetles, lacewings, syrphid ...

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Common Name:- Plum Pox(Shakra)
P_plumpox Plum pox disease is caused by a virus the plum pox virus (PPV). It is also known as Sharka, and can infect a variety of stone fruit species including peaches, apricots, damsons, greeng...
Caused by:- The Plum Pox Virus
Control:- The only way to control this disease is to destroy all infected tre...

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Common Name:- Plum Rust
P_plumrust1 The top of leaves become discoloured by yellow-orange spots found in mid-summer onwards. The underside of the leaf is covered with numerous brown/black markings. In extreme cases the whole tree will be affected and the leaves fall early. The fung...
Caused by:- The Fungus Tranzschelia pruni-spinosa
Control:- This disease is common and widespread. Consistent attacks may weake...

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Common Name:- Plum Sawfly
P_plumsawfly The Plum sawfly Hoplocamps fuava lays its egg in the embryonic plum at flowering time. The cream/white larvae burrow into the young plum causing exude a sticky resin. It also distort and causes the fruit to fall early. After being fully fed, the l...
Caused by:- The sawfly Hoplocamps fuava
Control:- Remove damaged fruit from the tree as well as any that have fallen ...

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Common Name:- Pocket Plum
P_pocketplum Plum pocket also called bladder Plum gall, is caused by the fungus Taphrina pruni, which is related to the Peach Leaf Curl fungus, that affects apricot and black cherry, plums, damsons ...
Caused by:- The fungus Taphrina pruni
Control:- Remove infected branches, witches’ brooms and fruit before spores a...

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Common Name:- Pollen Beetles
P_pllnbtles Pollen Beetles of the Meligethes genus is more of a nuisance than a pest and Meligethes aeneus is the most abundant pollen beetle in the UK. Mostly, the beetles do little harm although occasionally they may nibble into unopened flower buds.
...
Caused by:- The Beetles of Meligethes Genus
Control:- Pollen beetle larvae are attacked by at least three major species o...

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Common Name:- Poor Pollination
P_prpolnatrs Poor pollination can have a myriad of causes, from Cold weather, Hot weather, Too dry, too wet, soil pH imbalance, Mineral and/or Nutrients Levels too high, or too low, fungi and bacteria attack, lack of pollination species for self-infertile plan...
Caused by:- Many causes
Control:- If insect pollinators are scarce and the plant is self fertile shak...

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Common Name:- Poplar Bacterial Canker
P_popbaccnkr Most poplar cankers are caused by fungi. Poplars are attacked by several different types of canker. Poplar Bacterial Canker is caused by the bacteria Xanthomonas populi, but another bacteria Pseudomonas syringae pv. syringae may also attack poplar...
Caused by:- The Bacteria Xanthomonas populi
Control:- Good husbandry and cleaning pruning tools between use and pruning o...

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Common Name:- Poplar Yellow Leaf Blister
P_popyellfbltr Poplar Yellow Leaf Blister is caused by the fungus Taphrina populina, a plant-parasitic member of the Class Archaeascomycota which is related to the fungus that causes Peach Leaf Curl.<...
Caused by:- The Fungus Taphrina populina
Control:- Spraying with a suitable fungicide before bud break and when the le...

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Common Name:- Potassium Deficiency
P_potashdef Potassium is important to plant growth and development it provides the appropriate ionic environment for metabolic processes and growth regulation. Potassium helps plants grow faster, Use water better and be more drought resistant, Fight off dise...
Caused by:- Various causes
Control:- Foliar feedind in the short term will help with this deficiency. Ap...

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Common Name:- Potato Black Dot
P_potblkdot Black dot is a fungal disease caused by the fungus Colletotrichum coccodes and is a superficial blemish on potato tubers and also the plants.
In the plant it can infect the vascular system causing wilt, and some tubers may rot.
The s...
Caused by:- The Fugus Colletotrichum coccodes
Control:- There does not appear to be any resistant varieties, early varietie...

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Common Name:- Potato Black Leg
P_potblkleg Potato Blackleg is a bacterial rot caused by the bacterium Pectobacterium atrosepticum (formally known as Erwinia carotovora pv. atroseptica). The infection starts as a black lesion at the base of the stem, which leads to foliage collapse followed...
Caused by:- The Bacteria Pectobacterium atrosepticum
Control:- There are no chemical controls available to gardeners for blackleg....

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Common Name:- Potato Common Scab
P_potcomscab Potato Common Scab is a bacterial disease of potato skin, which cause rough, scabby patches on the surface of the tubers.
Common scab is caused by the bacteria Streptomyces scabies which can be serious on potatoes, beetroot, carrots, radish...
Caused by:- The Bacteria Streptomyces scabies
Control:- In a garden where irrigation is available, scab can be reduced by k...

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Common Name:- Potato Cyst Eelworm
P_potcysteel Cysts of yellow potato cyst nematode Picture by Bonsak Hammeraas, Bioforsk - Norwegian Institute for Agricultural and Environmental Research, Bugwood.org.
There are two forms of Potato Cyst Eelworm or Nematode that attack and damage potatoes...
Caused by:- Two Nematodes of the Heterodera Genus
Control:- Infestations of Potato Cyst Eelworm can be predicted by monitoring ...

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Common Name:- Potato Dry Rot
P_potdryrot Potato Dry rot is caused by the fungus Fusarium several species of which have been attributed as causing Potato Dry Rot. Some are Fusarium sambucinum, Fusarium graminearum, Fusarium. solani var coeruleum, and Fusarium avenaceum; F. sambucinum is ...
Caused by:- The Fusarium fungi species
Control:- Dry rot can be reduced or even halted if a proper storage environme...

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Common Name:- Potato Early Blight.
P_potearblight Potato Early Blight is a common and sometimes serious disease which also attacks other members of the Solanaceae family. It is caused by the fungus Alternaria solani which has a worldwide distribution and can withstand repeated wet and dry conditi...
Caused by:- The Fungus Alternaria solani
Control:- Try to get all the potatoes out from the ground at harvest time.<br...

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Common Name:- Potato Gangrene
P_potgangrrot Potato Gangrene is a rot of the potato tuber usually in storage and is caused by the fungus Phoma exigua var. foveata which is a soil bourn pathogen.
Stems may become infected and in turn infect tubers. Infection of tubers mainly through sk...
Caused by:- The fungus Phoma exigua var. foveata
Control:- Potato Gangrene can be reduced if a proper storage environment is p...

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Common Name:- Potato Hollow Heart
P_potholhrt Potato Hollow Heart is a physiological disorder where the center of the tuber is hollow often in a star shape. This is often preceded by a brown center. To date no pathogen is associated with this condition and the tubers are safe to eat after cut...
Caused by:- Abrupt Changes In Growing Conditions
Control:- Avoid abrupt changes in growing conditions and manage watering sy...

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Common Name:- Potato Internal Rust Spot
P_potintrstspt Potato Internal Rust Spot is believed to be a physiological condition, probably due to low levels of calcium. It often occurs on light sandy soils which lave low organic content. Stress and high temperatures later in the season is also implicated ...
Caused by:- Soil lacking in Calcium and or Organic Matter
Control:- Incorporate organic matter into the soil before planting and apply ...

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Common Name:- Potato Late Blight
P_potblight Potato Late Blight is one of the worst disease problems for the potato grower and in history it is the cause of the Irish famine from 1845 to 1855. It can wipe out the plants almost overnight and, worse still, it can infect the tubers from the abo...
Caused by:- The Fungus Phytophthora infestans
Control:- Try to get all the potatoes out from the ground at harvest time.<br...

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Common Name:- Potato Powdery Scab
P_potpowscab Potato Powdery scab is caused by the fungus or slime mould Spongospora subterranea which first shows as small raised pimples beneath the skin. It also infects tomato roots and a few other plant species and is widespread in potato growing countries...
Caused by:- The Fungus Spongospora subterranea
Control:- Planting powdery scab-free seed will aid in control, as will avoidi...

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Common Name:- Potato Silver Scurf
P_potsilscurf Silver Scurf is a fungal disease of the potato tuber skin or periderm. It is caused by the fungus Helminthosporium solani and can infect tubers by either primary or secondary infection. Primary infection is caused by infected plant debris and seed...
Caused by:- The Fungus Helminthosporium solani
Control:- There does not appear to be any resistant varieties, but a visit to...

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Common Name:- Potato Spraing
P_potspraing Potato Spraing is a disease of potato tubers caused by two viruses the Potato Mop-Top Virus and the Tobacco Rattle Virus. Both viruses causes similar symptoms which are arcs of brown streaks in the flesh of the potato. Tobacco Rattle Virus is tran...
Caused by:- Two Viruses
Control:- Some varieties show good levels of resistance. Visit <a href="http:...

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Common Name:- Potato Viruses
P_potvirus Alfalfa mosaic virus on potato leaves. Picture from Wikimedia Commons.
Potatoes can be infected by many different viruses most will reduce yield and or tuber quality, but some are often symptomless or
In many cases, the symptoms are...
Caused by:- Various Viruses
Control:- Some varieties show some resistance to some viruses, therefore A vi...

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Common Name:- Potato Wart Disease
P_potwartdis Potato wart disease, caused by the fungus Synchytrium endobioticum, which is soil-borne and affects a number of other Solanum species. It was once a very serious disease of potato and is subject to quarantine restrictions around the wold. These q...
Caused by:- The Fungus Synchytrium endobioticum
Control:- Follow <a href="http://www.defra.gov.uk/planth/ph.htm"><font color=...

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Common Name:- Powdery Mildew
P_powderymldw Although several Powdery Mildew fungi are non specific, often different powdery mildew fungi tend to infect either plants in the same family or only one species of plant. Some powdery mildew occur on top of the leaves, stem, flowers and fruit and ...
Caused by:- Various Fungal spores
Control:- The best method of control is prevention therefore good hygiene and...

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Common Name:- Primula Brown Core
P_primulabrowncore Primular, Polyanthus and related plants grows slowly and leaves will yellow early. Plants wilt easily and the root system deteriorates. If roots are cut lengthwise there is a distinctive brown discolouration in the core. The fungus builds up in th...
Caused by:- The Fungus Phytophthora primulae
Control:- Remove infected plants as soon as possible. Soak the soil with Jaye...

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Common Name:- Privit Thrips
P_privetthrip The Privet Thrips, Dendrothrips ornatus (Thysanoptera: Thripidae) is an insect that is mainly a summer pest. Especially if the summer is hot and dry. In some countries they are called thunder flies. Although the plants recover well from attacks th...
Caused by:- The Insect Thrip Dendrothrips ornatus
Control:- There are several natural enemies such as <a href="/pests/269?telep...

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Common Name:- Proliferation Mutation
P_prolifmut One of many mutations or disorders that can affect plants is proliferation, which can affect of a range of plants. It is when one or more buds form in an already open bloom. The reasons for this is not known, but is probably the imbalance of hormo...
Caused by:- Various causes
Control:- There is rarely any need to take control measures unless it is happ...

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Common Name:- Pyracantha Leaf Miner
P_pycnthalfmnr Pyracantha(Firethorn) Leaf Miner Phyllonoryceter leucographella is the larvae of a moth of the Gracillariidae family and was unknown in the UK until about 1989.
This moth lays their eggs on the midrib of leaves of Pyracantha. They are pale ...
Caused by:- The Leaf Miner Phyllonoryceter leucographella
Control:- Leaf miners are difficult to control since they spend most of their...

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Common Name:- Pyracantha Scab
P_pyrcntrscab Pyracantha scab is a fungal disease of the blossoms, leaves and fruit of Pyracantha(firethorn), resulting in early leaf fall, loss of flowers and disfigured fruit. It is caused by the fungus Spilocaea pyracanthae, which also attacks Cotoneaster, E...
Caused by:- The Fungus Spilocaea pyracanthae
Control:- There are some fungicide sprays that will cure this scab, but spray...

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Common Name:- Pythium Root Rot
P_pythiumrtrt Pythium disease on Cowpea Picture by Howard F. Schwartz, Colorado State University, Bugwood.org.
Pythium Root Rot is a common plant disease caused by a genus of organisms called Pythium of the Pythiaceae family. They are closely related to ...
Caused by:- Various Species of the Pythium Genus
Control:- Remove infected plants as soon as possible along with the soil arou...

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Q
Common Name:- Quince Leaf Blight
P_quincelfblt Quince Leaf Blight is caused by the fungus Diplocarpon maculatum which is related to the fungus causing black spot in roses. It can be a nuisance on quince trees(Cydonia oblonga), the flowering quince (Chaenomeles) and all varieties of quince in h...
Caused by:- The FungusDiplocarpon mespili(Fabraea maculata)
Control:- Spray your quince tree with a copper based fungicide immediately an...

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Common Name:- Quince Powdery Mildew
P_quincepwdmld Powdery Mildew on Corgette.
Quince Powdery mildew is caused by the fungus Podosphaera leucotricha and also infects apples, pears, and other fruit trees. This fungus is found in nearly all parts of the world where these fruits are grown are ...
Caused by:- The Fungus Podosphaera leucotricha
Control:- The best method of control is prevention therefore good hygiene and...

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Common Name:- Quince Rust
P_qncerust The Quince Rust is caused by the fungus Gymnosporangium clavipes and like most rust diseases needs two hosts to complete its life cycle. The full name of this disease is Cedar-Quince Rust. Cedar-Hawthorn Rust (G. globosum), and Cedar-Apple Rust (G...
Caused by:- The Fungus Gymnosporangium clavipes
Control:- Monitoring rust canker on red cedar trees and temperatures during w...

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R
Common Name:- Rabbits
P_rabbit Rabbits are sometimes a problem in the garden as they eat herbaceous plants to the ground and chew the bark of trees at soil level which can kill the tree. They also dig a warren of tunnels in the soil thereby making a mess.
Caused by:- Rabbit (Oryctolagus cuniculus)
Control:- A strong wire mesh fence with mesh size no larger than 25mm buried ...

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Common Name:- Raspberry Beelte
P_rasbbtle The raspberry beetle Byturus tomentosus and it's larve, is one of the most destructive and annoying pest of raspberries, blackberries and loganberries, especially as they are not found until the ripe raspberries are picked and are being prepared f...
Caused by:- The Beetle Byturus tomentosus
Control:- The early fruiting berries are most likely to be affected, therefor...

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Common Name:- Raspberry Cane Blight
P_raspcnblt Raspberry Cane Blight is caused by the fungus Leptosphaeria coniothyrium which survives in the soil and enters the base of canes through splits in the bark, often the result of cane-midge attacks.
Dark patches appear on the canes, in May or...
Caused by:- The Fungus Leptosphaeria coniothyrium
Control:- Once spotted cut out and burn any affected canes. Cut back to below...

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Common Name:- Raspberry Cane Spot
P_raspcnspot Raspberry Cane Spot is caused by the fungus Elsinoë veneta which also affects Loganberry and Blackberry fruits. The symptoms are small purple spots that appear on the canes in May or June and gradually increase in size to form cankers which look l...
Caused by:- The Fungus Elsinoë veneta
Control:- Once spotted cut out and burn any affected canes. Cut back to below...

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Common Name:- Raspberry Leaf and Bud Mite
P_rasplfbdmite Raspberry Leaf and Bud Mite Phyllocoptes gracilis belongs to the Eriophyoidea or Tetrapodili which is a superfamily of herbivore mites. These mites are tiny sap-sucking pests that lives on the underside of the leaves during summer and overwinters ...
Caused by:- The Mite Phyllocoptes gracilis
Control:- Many acaricide and insecticides have been removed from sale due to ...

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Common Name:- Raspberry Rust
P_rasprust Raspberry Rust caused by Phragmidium rubi-idaei is a common, but rarely a serious fungal disease, but it can cause early leaf drop and reduced vigour.
This rust fungi like most Rust<...
Caused by:- The Rust Fungi Phragmidium rubi-idaei
Control:- Spray with a systemic fungicide as well as other fungicides especia...

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Common Name:- Raspberry Spur Blight
P_raspsprblt Raspberry Spur Blight is a common fungal disease caused by the fungus Didymella applanata it also occasionally attacks loganberries and is is particularly common during wet seasons. It causes purple patches in early Summer, centred around the buds...
Caused by:- The Fungus Didymella applanata
Control:- Spray with a systemic fungicide as well as other fungicides especia...

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Common Name:- Raspberry Viruses
P_raspvirus There are many viruses that attack Raspberries. Sometimes red varieties are immune to the effects whereas black varieties are not. Some viruses are notifyable and you should inform your local Plant Health Inspector or Caused by:- Various Viruses
Control:- There is no cure for viruses and plants are best destroyed as soon ...

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Common Name:- Rats
P_rats There are two main species of rats found around the world, both originate in the plains of Asia. The most common is the brown rat Rattus norvegicus and the black rat, Rattus rattus. The black rat is mainly associated with the plague in the middle ...
Caused by:- The mamals Rattus norvegicus and Rattus rattus
Control:- There are several things that can be done to discourage them in y...

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Common Name:- Red Spider
P_redspider1 Two genus of pest have the common name Red Spider mite. One is the Fruit Tree Red Spider mite — Panonychus ulmi — which mainly attacks vine as well as fruit trees such as apple, pear, cherry, currant bush and cane fruits. The other red spider ...
Caused by:- Red Spiders Tetranychus urticae & Panonychus ulmi
Control:- The best control is to spray with a systemic insecticide, but this ...

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Common Name:- Redberry Mite
P_redbrymte The Redberry Mite Acalitus essigi are microscopic members of the arachnid class(mites, spiders, false scorpions, harvestmen etc.) and the Eriophyidae family(Gall mites). This mite is highly specialised and can be a serious pest of commercially-pro...
Caused by:- The Eriophyid mite Acalitus essigi
Control:- Spraying in the spring with horticultural oils, in the dormant peri...

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Common Name:- Reversion
P_reversion Flowers of the George Lindley Taber variety of azalea, featuring a single flower from the same plant, in a reversion to the Omurasaki sport. Picture from Wikimedia Commons.
Reversion is when a plant known for a particular leaf shape, varieg...
Caused by:- Various Causes
Control:- Shoots that have reverted are usually much more vigorous than the v...

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Common Name:- Rhododendron Bud Blast
P_rhodbdblst Rhododendron bud Blast is a fungal disease of Rhododendrons and Azaleas caused by the fungus Pycnostysanus azaleae, which affects the tight dormant flower buds. This fungus is associated with infestations of the
Caused by:- The fungus Pycnostysanus azaleae
Control:- Treating Rhododendron Bud Blast is best done by a two pronged attac...

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Common Name:- Rhododendron Lacebug
P_rhodolacebg Rhododendron Lacebug Stephanitus rhododendri is a pest of species of rhododendron, sycamore, azalea, and evergreen trees.
Lace bugs nymphs and adult stages, live on the underside of leaves along with blackish fecal material stuck to the lea...
Caused by:- The insect Stephanitus rhododendri
Control:- Eliminating lace bugs before hatching is necessary to avoid visible...

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Common Name:- Rhododendron Leaf Hopper
P_rhodolfhpr The Rhododendron Leafhopper Graphocephala fennahi also known as the Rhododendron Cicada or the Green and Scarlet Leafhopper is a striking Green and purple insect that was native to the Americas until around 1900 when it was introduced to Europe an...
Caused by:- The insect Graphocephala fennahi
Control:- Repeated spraying in the Spring and Early Summer should eradicate t...

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Common Name:- Rhododendron Leaf Spot
P_rhodolfspt Septoria azalea leaf spot. Picture by Florida Division of Plant Industry Archive, Florida Department of Agriculture and Consumer Services.
Rhododendron Leaf Spot is usually a fungal problem which results in rounded spots on the leaves. Seve...
Caused by:- Various Causes
Control:- If the leaf Spots are from fungi, which is more prevalent during we...

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Common Name:- Rhododendron Petal Blight
P_rhodoptlblt Rhododendron Petal Blight is caused by the fungus Ovulinia azalea although other fungi like Cercospora handelii, Phytophthora ramorum and Botrytis cinerea also causes these spots. Some of these fungi also affects other trees and plants.
It ...
Caused by:- The Fungus Ovulinia azalea and others
Control:- Remove and destroy infected flowers as soon as possible to minimise...

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Common Name:- Rhododendron Powdery Mildew
P_rhodopowmdw Rhododendron Powdery Mildew is caused by a few fungi probably from the Erysiphe (Microsphaera) Genus of fungi. Infection occurs in the spring or early summer, or may be carried over from the previous growing season. The symptoms are diffuse pale ...
Caused by:- Erysiphe (Microsphaera) Genus of Fungi
Control:- Spraying with fungicides containing Sulphur from early spring at re...

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Common Name:- Rhododendron Rust
P_rhodorust Chrysomyxa rhododendri on Spruce tree. Picture by Joseph O'Brien, USDA Forest Service, Bugwood.org.
Rhododendron Rust is mainly caused by fungi from the genus Chrysomyxa. Many of these had been identified as Chrysomyxa rhododendri. Like mos...
Caused by:- Mainly Chrysomyxa species of Fungi
Control:- As with any fungal disease one of the best ways of preventing it is...

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Common Name:- Robins Pincushion
P_robpincshn Robin's pincushion gall, Moss gall or Rose bedeguar gall develops on the common dog rose(Rosa canina) in late summer and autumn. This gall like most other galls are induced by insects feeding on the plant. In this case it is a wasp Diplolepis rosa...
Caused by:- The Wasp Diplolepis rosae
Control:- Controlling gall insects is best done before or just after the wasp...

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Common Name:- Root Aphids
P_rootaphids Root Aphids have a similar life cycle as normal Aphids, but instead of attacking the above ground parts of the plant they attack the roots of the plant. Like ordinary Aphids they suck th...
Caused by:- Various Aphids
Control:- Insecticides and insecticidal soaps can be applied as a soil drench...

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Common Name:- Root Knot Eelworms
P_rootkntneel Root Knot Eelworm is caused by several species of belonging to the Meloidogyne(Heterodera) Genus. In the northern climates it is mainly a pest of the greenhouse, but can infes...
Caused by:- Nematodes of the genus Meloidogyne(Heterodera)
Control:- Clear up infected plant debris and weed out unwanted plants.<br /> ...

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Common Name:- Root Mealybugs
P_rtmealybug Root or Ground Mealybugs are insects in several Genus like Cataenococcus, Geococcus, Pseudoccous or Rhizoecus of the family Pseudococcidae, and there are many species around the world. They prefer warm areas and therefore in the UK there are main...
Caused by:- Various Genus of the Pseudococcidae Familly
Control:- Root Mealybug is very difficult to control and every efforts should...

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Common Name:- Rose Aphids
P_roseaphid Roses are attacked by two types of aphids namely Greenfly and Blackfly. These aphids suck the sap and therefore take the strength out of Roses if not checked as soon as possible. They also transmit other viruses and diseases to the roses.
T...
Caused by:- The insect aphid Macrosiphum rosae
Control:- As an emergency quick solution I squish them between the fingers ...

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Common Name:- Rose Black Spot
P_blacksopt3 Rose black spot is specific to roses and all types are susceptible. It is caused by the fungus Diplocarpon rosae which kills the cells on the leaves of roses leaving brown to black spots on leaves. The spots may join together or remain separate.
Caused by:- The Fungus Diplocarpon rosae
Control:- Rake up and destroy fallen leaves in the autumn. Prune out all stem...

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Common Name:- Rose Bloom Balling
P_roseblmball Rose Bloom Balling is a condition where the flower bud develops normally to full size and starts to open, but the petals fail to open. It is caused by cool, damp conditions, often in a partially shady site, where the outer petals become waterlogge...
Caused by:- Weather Conditions
Control:- The only option is to cut off the damaged buds and wait for new o...

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Common Name:- Rose Grey Mould
P_mildew1 Rose Gray Mould is a common disease of hundreds of plants. It is especially problematic during periods of high rainfall and cool temperatures. It is caused by the fungus Botrytis cinerea
Caused by:- The fungus Botrytis cinerea
Control:- Controlling this fungus is often difficult as it is so widespread...

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Common Name:- Rose Leaf-rolling Sawfly
 p_roselfrlsfly The rose Leaf-rolling Sawfly Blennocolpa phyllocolpa lays its eggs in late Spring/Early Summer on the underside of the leaf and secrete a chemical that induces the leaf margins to curl downwards and inwards along their length forming a tube which ...
Caused by:- The Sawfly Blennocolpa phyllocolpa
Control:- Pick off any rolled up leaves before July as this when the larvae...

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Common Name:- Rose Leafhopper
P_roselfhpper The Rose Leafhopper Edwardsiana rosae can be a serious pest of rose, pear, apple and some hardwood trees by sucking the sap from the leaves. It resembles the White Apple Leafhopper, with whom it may co-exist, in appearance, habits, and damage to i...
Caused by:- The insect Edwardsiana rosae
Control:- Thorough spraying of infested plants with insecticide, preferably s...

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Common Name:- Rose Powdery Mildew
P_rosepwdmldw Rose Powdery Mildew is caused by the fungus Podosphaera(Sphaerotheca) pannosa. It is only one of many powdery mildews most of which are host specific to certain from cereals and grasses, to fruit trees, and broad-leaved shade trees.
The ma...
Caused by:- The Fungus Podosphaera(Sphaerotheca) pannosa
Control:- Improve circulation by pruning and keep the tree growing healthil...

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Common Name:- Rose Replanting Sickness
P_roserpltskns Rose sickness is a problem with roses where a rose has been removed and a new rose put in its place. The new rose either does not perform well or in some cases never properly establishes and dies. This problem lasts in the soil for many years.
Caused by:- Symbiosis fungi
Control:- Watering the soil with soil sterilant or removing most of the soil ...

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Common Name:- Rose Root Aphids
P_rosertaphd Rose Root Aphid Maculolachnus submacula have a similar life cycle as normal Aphids, but instead of attacking the above ground parts of the plant they attack the roots. Therefore they are...
Caused by:- The Aphid Maculolachnus submacula
Control:- Insecticides and insecticidal soaps can be applied as a soil drench...

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Common Name:- Rose Rust
P_roserust Rose rust is caused by the fungus Phragmidium tuberculatum and some other Phragmidium related species. Unlike most Rust, which have two hosts and each host produces spores that can only infect the other host, Rose Rust produces overwintering spore...
Caused by:- The Fungus Phragmidium tuberculatum
Control:- In the European Community the products permitted under organic regi...

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Common Name:- Rose Stem Canker and Dieback
P_rosestckrdbk There are several fungi that cause Rose Stem Canker and dieback. The most prevalent is Coniothyrium wernsdorffiae and others are Coniothrium fuckelii(Diaplella coniothyrium), Cryptosporella umbrina(Diaporthe umbrina), Phomopsis, Coniothyrium and A...
Caused by:- Various Fungi
Control:- Ensuring vigorous growth and removal of dead canes and stubs will h...

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Common Name:- Rose Viruses
P_rosevruses Rose Virus diseases like all other viruses can only be seen under an electron microscope. Therefore the only way to identify a virus is usually by the leaf and flower patterning or the stunting effect of the virus.
Virus symptoms may only a...
Caused by:- Various Viruses
Control:- The only cure is to remove and destroy by burning the infected plan...

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Common Name:- Rosy Apple Aphid
P_rosyaphd Rosy Apple Aphid, Dysaphis plantaginea, is one of several species of aphids that infest apple trees and like every aphid species suck the sap from the leaves and buds. The body of this aphid has a very waxy coating and usually a slight purplish or...
Caused by:- The Aphid Dysaphis plantaginea
Control:- Control depends on proper timing of insecticide applications. Overw...

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Common Name:- Rust
P_rust2 There are many different fungi that causes rust in various plants or trees. The name is very descriptive as rust often looks like a piece of iron going rusty. Often, but not always it is Orange-brown pustules that develop initially on the undersid...
Caused by:- Various Fungal spores
Control:- In the European Community the products permitted under organic regi...

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S
Common Name:- Salt Damage
P_saltdamage Salt in high concentration damages plants in many ways. First it raises the osmosis pressure of the soil by its high concentrations of sodium and chloride ions. This makes it difficult for the plant to take up water even though it is abundant. Thi...
Caused by:- Too much salts
Control:- Where you cannot avoid salt ensure good drainage so the salty wat...

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Common Name:- San Jose Scale Insect
P_sanjsescle The San Jose scale Quadraspidiotus perniciosus (Aspidiotus perniciosus, Comstockaspis perniciosa, Diaspidiotus perniciosus) insect is an extremely important pest pest of Apple, Peach, Pear and Plums and many more trees and plants. It is a quaranti...
Caused by:- The Scale Insect Quadraspidiotus perniciosus
Control:- Insecticidal sprays applied to developing overwintered individuals,...

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Common Name:- Sappy Bark
P_paperybk Sappy bark, which is also called pPapery Bark, is a fungal disease that causes the sapwood to go become spongy especially in wet weather. It is caused by the fungus Trametes versicolor and is a fungal disease of apple and some stone fruit trees. T...
Caused by:- The FungusTrametes versicolor
Control:- Trees should be invigorated by ensuring good drainage, maintaining ...

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Common Name:- Sawflies
P_sawfly The Blackheaded Ash Sawfly Tethida barda Adult and larvae. Picture by David Cappaert, Michigan State University and Lacy L. Hyche, Auburn University, Bugwood.org.
Sawfly is the common name for insects belonging to suborder Symphyta of the o...
Caused by:- Various Sawflies
Control:- Picking the larvae by hand can be done if the infestation is not ...

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Common Name:- Scale Insects
P_scaleinsects1 Scale insects are sap-sucking, limpet-like insect pests that weaken the growth of the host plant and can infest a wide range of ornamental plants and fruit trees.
They are usually easily seen as scales or shell-like bumps on plant stems and...
Caused by:- Several types of insects
Control:- In warm environments, like greenhouses, biological control can be u...

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Common Name:- Sciarid Flies
P_fungusgnats Scairid Flies or Mushroom flies are aslo called Fungus Gnats because it has been proven to carry various fungus spores on its body from one place to another. The main species is Bradys...
Caused by:- Many Genus and species of the Order Diptera
Control:- Allow the surface of composts to dry out a little before watering t...

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Common Name:- Sclerotinia Rot
P_slerotina Sclerotina Rot is caused by the fungal pathogen Sclerotinia sclerotiorum which has of a wide range of host from leaves, stems, fruit and roots in storage. The spores(sclerotium (plural sclerotia) which resides in the soil for at least five years n...
Caused by:- The fungus Sclerotinia sclerotiorum
Control:- As with any fungal disease one of the best ways of preventing it ...

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Common Name:- Scorching
P_scorch Scorch is caused by too much sun or by chemicals that the plant cannot cope with. It is particularly prevalent when water is on the leaves. The water droplets concentrate the sun rays and kill the cells of the leaves or petals. This is one reason ...
Caused by:- Too Much Sun
Control:- Take care when watering water in the early evening or very early in...

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Common Name:- Seiridium Canker
P_seiridcnkr Seiridium cankers, also called coryneum canker, are caused by the fungus Seiridium unicorne which needs a wound or crack in the outer defences of the tree. This is why trees under drought or other stress may succumb easily.
All Seiridium ca...
Caused by:- The Fungus Seiridium unicorne
Control:- The best control for Seiridium cankers is irrigating trees during p...

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Common Name:- Shakra(Plum Pox)
P_plumpox Plum Pox disease is caused by a virus the plum pox virus (PPV). It is also known as Sharka, and can infect a variety of stone fruit species including peaches, apricots, damsons, greeng...
Caused by:- The Plum Pox Virus
Control:- The only way to control this disease is to destroy all infected tre...

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Common Name:- Shanking
P_shanking Shanking is the technical term, where grapes do not ripen properly. It is also applied to Cabbages and other winter crops in the field that do not develop. In all cases it is caused by a restriction of the flow of plant nutrients. In grapes indiv...
Caused by:- Inadequate Growing Conditions
Control:- Use a foliar spray feed as soon as possible during berry developmen...

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Common Name:- Sharka
P_plumpox Sharka or Plum Pox disease is caused by a virus the plum pox virus (PPV) and can infect a variety of stone fruit species including peaches, apricots, damsons, greengages, plums, nectar...
Caused by:- The Plum Pox Virus
Control:- The only way to control this disease is to destroy all infected tre...

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Common Name:- Shieldbugs
P_shieldbugs The Green Shieldbug Acrosternum hilare Picture by Frank Peairs, Colorado State University, Bugwood.org.
There are several Genus of Shieldbugs which are named after their sheild like shape. They are also called chust bugs, and Caused by:-
Various Members of the superFamily Pentatomoidea
Control:- Usually no action is needed as they are rare and can be ignored, bu...

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Common Name:- Shothole Borers.
P_shotholebrs Shothole borer Scolytus rugulosus Picture by Clemson University - USDA Cooperative Extension Slide Series, Bugwood.org.
Many species are known as Shothole Borers which are tiny brown or black beetles from the family Scolytidae that attack m...
Caused by:- Various species of the Scolytidae Family
Control:- White latex paint or stem wrappers on trunk and stems can protect t...

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Common Name:- Shothole leaves
P_shothole Stigmina fungus on Prunus picture byWhitney Cranshaw, Colorado State University, Bugwood.org.
Shothole in the leaves of plants is caused by a variety of different causes such as bacterial or fungal pathogens as well as some insect pests. I...
Caused by:- Various Bacteria, fungi and insects
Control:- To most effective prevention of leaf spot, apart from spraying with...

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Common Name:- Silver Fir Adelgid
P_blsmwlyadel Silver Fir Adelgid is known as the Balsam Woolly Adelgids, Adelges piceae and is a is a tiny, non-flying, sap sucking insect that attacks mainly Abies species of trees.
They are...
Caused by:- The Adelgid Adelges piceae
Control:- Spraying with insecticides is effective, but costly and is difficul...

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Common Name:- Silverleaf Fungus
P_slvrleaf Silverleaf Fungus Chondrostereum purpureum(Stereum purpureum) is found in temperate climates world-wide and attacks most species of the tree family Rosaceae, particularly the genus Prunus. The disease is progressive and often fatal and is more of ...
Caused by:- The Fungus Chondrostereum purpureum
Control:- Since the fungus produces most of its infectious spores in autumn a...

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Common Name:- Slime Flux
P_slimeflux Slime flux is a bacterial disease also called Bacterial Wetwood which attacks many trees such as apple, ash, aspen, beech, birch, cottonwood, elm, fir, hickory, maple, mulberry, oak, p...
Caused by:- Various Bacteria, Fungi and Yeast
Control:- It can be difficult to prevent the stem damage that leads to the de...

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Common Name:- Slime Moulds
P_slimemlds Fruiting slime mold. By ancient trail near confluence of East and West forks of the Hood River - east bank. Trail starts at end of Iowa Drive, Hood River, OR 97031. Picture by Adrian Eugene Fields from Wikimedia Commons.
Slime moulds were f...
Caused by:- Various species of the Protista Kingdom
Control:- No chemical control is necessary as plant growth is usually not aff...

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Common Name:- Slugs
P_slugs1 Slug is a gastropod molluscs that lacks a shell and most have evolved from snails that gradually lost their shells. In the Uk there are 29 species and most live on living and decaying plant tissue. Some plants like Delphiniums, Hostas, Marigolds, ...
Caused by:- Several species of slugs
Control:- There are hundreds of methods for killing or eradicating slugs some...

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Common Name:- Small Ermine Moths
P_smlermmths There are several species of Small Ermine Moths, which are small, whitish, elongated moths having a row of black dots along the sides of the body when the wings are folded and are about 1cm long. Some can defoliate certain plants trees or shrubs f...
Caused by:- Various species of Ermine Moths
Control:- Light infestations can be pruned out. Otherwise Spray forcible with...

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Common Name:- Smuts
P_smuts Corn Smut Ustilago maydis Picture by Florida Division of Plant Industry Archive, Florida Department of Agriculture and Consumer Services, Bugwood.org.
Smuts are multicellular, parasitic, basidiomycete fungi of the order Ustilaginales that c...
Caused by:- Various Fungi of the Ustilaginales
Control:- The in most cases the fungus is present throughout the plant the in...

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Common Name:- Snails
P_snails1 Snails! What can I say, you either love them or hate them. I cannot make up my mind, but on the whole I hate them as they destroy many of my plants by eating them. On the other hand they do me a service in converting plant matter to fertiliser. Th...
Caused by:- The Snail Helix aspersa or Capaea species
Control:- There are many ways to get rid of snails from the garden, but none ...

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Common Name:- Snow Moulds
P_snowmld Snow mould fungi are active when the temperature is just above freezing and in moist conditions. These conditions occur most frequently under snow cover or anything else that covers the grass, such as fallen leaves.
Snow mould in grass is c...
Caused by:- Two Fungi Fusarium nivale or Typhula incarnata
Control:- The best way of preventing or reducing snow mould problems in lawns...

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Common Name:- Snowdrop Grey Mould
P_sndrpgrymld Grey mould on snowdrops(Galanthus [Gk. gala, milk; anthos, flower]) is caused by the fungus Botrytis galanthina and is closely related to the grey mould fungus Botrytis cinerea. This fungus only attacks Galanthus spp. especially in mild damp winte...
Caused by:- The Fungus Botrytis galanthina
Control:- Dig up affected plants along with some soil, and destroy preferable...

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Common Name:- Soft Rot
P_softrot Soft Rot is also called Bacterial Soft Rot as it is usually caused by various bacteria. Tubers, root and fruit are usually affected, but there is a wide range of host like potato, sweet...
Caused by:- Various Bacteria
Control:- Good husbandry and disease management is based primarily on sanitat...

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Common Name:- Soft Scale Insect
P_sftscleinct There are many kinds of Scale Insects all are specialised, limpet-like, immobile insects attached to some part of a host from which they suck the sap often exuding the sap sugars called...
Caused by:- The Scale Insect Coccus hesperidum
Control:- In warm environments biological control can be used in greenhouses ...

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Common Name:- Solomon Seal Sawfly
P_solslswfly The larval stage of Solomon’s Seal Sawfly Phymatocera aterrima can completely defoliate Polygonatum species and hybrids by early summer. These slow moving, grey, caterpillar-like larvae seems to suddenly appear from early June to July. During this...
Caused by:- The Sawfy Phymatocera aterrima
Control:- Remove the larvae from the underside of damaged leaves.<br /> Spra...

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Common Name:- Sooty Canker
P_sootyckr Sooty canker is a wilt disease of branches and is caused by the fungus Nattrassia mangiferae (formerly Hendersonula toruloidea) and usually occurs over several seasons. This fungal spores can cause lung disease in humans.
The fungus enters ...
Caused by:- The fungus Nattrassia mangiferae
Control:- Wear masks when handling the black spore infected branches.<br /> ...

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Common Name:- Sooty Mould
P_sootymld The Sooty Moulds is a secondary affliction which grows on and feeds on the honeydew excreted by insects and which falls on the leaf surface. Plant leaves and stems or branches in extreme cases, become blackened and are usually sticky to the touch....
Caused by:- Usually Various Sap Sucking insects
Control:- There is no direct control measures for sooty mould, but deal with ...

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Common Name:- Sparrows
P_sparrows The Sparrows Passer domesticus is probably the most often seen of British birds, also known as House Sparrows they live in close proximity to man and build their nests in holes, thatch, hedges, sheds, warehouses and anywhere with an easy source of...
Caused by:- The Bird Passer domesticus
Control:- NOTE: The Dunnock, a close relative of the house sparrow and a prot...

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Common Name:- Spinach Leafminer
P_beetleafminer4 There are at least two Spinach Leafminer of the Pegomya species. One Pegomya hyoscyami is the same as the beet leafminer. They are small anthomyiid flies whose larvae attack the leaves of spinach, beets, Swiss chard, lambs quarter, and other weed...
Caused by:- The Larvae of Pegomya species
Control:- If the infestation is not large it is possible to remove the affect...

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Common Name:- Splitting
P_splitting Fruits such as apples, cherries, pears, plums, tomatoes and others of various kinds are prone to splitting. This is not a disease, but is usually due to environmental conditions. The main environmental conditions is sharp changing in growing condi...
Caused by:- Environmental Conditions
Control:- The best way to avoid splitting is to keep conditions as even as po...

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Common Name:- Springtails
P_springtails There are many Genus and species of Springtails, which belong to the Order Collembola. Their habitats range from snow covered with algae to the intertidal areas on the shoreline. All require a moist or wet environment and can emerge any time of th...
Caused by:- Insects from the Order Collembola
Control:- In the house Springtails are easily eradicated by several means suc...

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Common Name:- Squirrels
P_squirrels Squirrels belong to the large taxonomic family Sciuridae. The family includes tree squirrels, ground squirrels, chipmunks, marmots (including woodchucks), flying squirrels, and prairie dogs. Squirrels are indigenous to the Americas, Eurasia, and A...
Caused by:- Members of the Family Sciuridae
Control:- Any management methods needs to be over a wide area as squirrels ...

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Common Name:- Stem and Bulb Eelworm
 p_narcissuseelworm1 There are many, many Eelworm(nematode) a few are benficial and sold as biological control for such things as slugs and leatherjackets etc, but most are pests in various plants. Most are microscopic and live in the soil, but there is also some that...
Caused by:- The Nematode Ditylenchus dipsaci
Control:- Good hygiene by removing dead plant materials, crop rotation, wee...

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Common Name:- Stink Bugs
P_shieldbugs The Green Shieldbug Acrosternum hilare Picture by Frank Peairs, Colorado State University, Bugwood.org.
There are several Genus of Stink Bugs which are named after their sheild like shape. They are also called chust bugs, and Caused by:-
Various Members of the superFamily Pentatomoidea
Control:- Usually no action is needed as they are rare and can be ignored, bu...

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Common Name:- Storage Rots
 p_storerots Fruits, Bulbs, Roots and Tubers start to rot during storage. In many cases the rot is initialised when the plant was producing the above storage items and the storage conditions makes rotting inevitable.
In some cases the rotting agent is p...
Caused by:- Various Fungi, Bacteria, Viruses or Worms.
Control:- Properly clean and sterilise storage containers or rooms.<br /> Al...

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Common Name:- Strawberry Black Eye
P_stbryblkeye Strawberry Black Eye is a physiological problem caused by a late frost when the Strawberry flowers have opened. The frost damages the central florets of the flower causing it to turn black, but the petals remain white. Affected flowers will not se...
Caused by:- Frost Damage
Control:- Avoid planting strawberries in areas known tho be frost pockets o...

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Common Name:- Strawberry green Petal
P_stbrygnptl It is believed that a virus or less likely a phytoplasma is responsible for the flowers of strawberries to revert to forming leaves, which is known as Strawberry Green Petal.
The flowers are reduced in size with green petals and few if any ...
Caused by:- A virus or phyotplasma
Control:- Destroy and replace plants as soon as yields begin to fall, usually...

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Common Name:- Strawberry Grey Mould
P_stbrygrymld Strawberry Grey mould is caused by the fungus Botrytis cinerea which is widespread and also attacks many other plants. See below.
At flowering time, spores, blown by the wind, enter open flowers and lie dormant until the fruits begin to rip...
Caused by:- The Fungus Botrytis cinerea
Control:- Controlling this fungus is often difficult as it is so widespread s...

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Common Name:- Strawberry June Yellows
 p_stbryjnyell Strawberry June Yellows is a is a phytoplasma disease that affects strawberry plants. A pytoplasma is a very small (1 micrometre) bacteria like organism that are parasites of plant phloem tissue that transport nutrients around the plant. They are ...
Caused by:- The phytoplasma Candidatus Phytoplasma australiense
Control:- Plants should be removed and destroyed to protect other plants in t...

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Common Name:- Strawberry Leaf Spot
P_stbrylfspt Strawberry Leaf Spot is caused by the fungus Mycosphoerella fragarics and is perhaps the most common of strawberry diseases. It is also called spot disease, sun-burn, sun-scald, Leaf Blight, and sometimes mistaken for strawberry rust.
The f...
Caused by:- The Fungus Mycosphoerella fragarics
Control:- There are varieties that has varying degrees of resistance to thi...

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Common Name:- Strawberry Mite
P_stbymites There are several Tarsonemid mites that attack strawberries which all give similar symptoms. Strawberry mite Phytonemus pallidus(Steneotarsonemus) also known as the Cyclamen Mite is le...
Caused by:- The Tarsonemid Mite Phytonemus pallidus
Control:- A broad spectrum insecticide may cause more damage than a specifi...

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Common Name:- Strawberry Red Core
P_stbryrdcore Strawberry Red Core is a disease of the roots of the strawberry plant and is caused by the fungus Phytophthora fragariae. It is also known by other names such as Strawberry Red Stele, Lanarkshire disease because it was first reported from that are...
Caused by:- The Fungus Phytophthora fragariae
Control:- Disease incidence and severity can be minimised by having well drai...

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Common Name:- Strawberry Seed Beetle
P_stbrysdbtle The Strawberry Seed Beetle Harpalus rufipes is a significant pest of several crop species -- including grains, legumes and strawberries. It has a world wide distribution. The beetle is noted for removing and feeding on only the seeds from the surf...
Caused by:- The Beetle Harpalus rufipes
Control:- No effective insecticide is known, therefore it is best to keep are...

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Common Name:- Strawberry Viruses
P_stbryvirs Strawberry Crinkle Virus Cytorhabdovirus (SCrV) Picture by Dr W. Jelkman, Biologische Bundesanstalt für Land- und Forstwirtschaft, Bugwood.org.
There are probably over 30 viruses that can affect Strawberry plants(Fragaria species). Virus i...
Caused by:- Various Viruses
Control:- There is little that can be done when viruses strike and the only t...

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Common Name:- Sweetcorn Smut
P_smuts Corn Smut Ustilago maydis Picture by Florida Division of Plant Industry Archive, Florida Department of Agriculture and Consumer Services, Bugwood.org.
Sweetcorn Smut is caused by the fungus Ustilago maydis which is wind blown and infect any...
Caused by:- The Fungus Ustilago maydis
Control:- It is spread by water (rain or other) splashing from the infected p...

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Common Name:- Swift Moth
P_swftmoth The Common Swift Moth Picture by Jeffdelonge from Wikimedia Commons.
There are several species of Swift Moths, but the two most troublesome to gardeners are the Ghost Moth Hepialus humuli and the Common Swift moth Korscheltellus lupulina (f...
Caused by:- Moths of the Family Hepialidae
Control:- The Ghost Moth Picture by Engeser from Wikimedia Commons.There is n...

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Common Name:- Sycamore Anthracnose
P_sycantnose American sycamore (Platanus occidentalis L.) with anthracnose. picture by Joseph O'Brien, USDA Forest Service, Bugwood.org
Sycamore anthracnose is caused by the fungus Apiognomonia veneta(Gnomonia platani) which is the same fungus that caus...
Caused by:- The Fungus Apiognomonia veneta(Gnomonia platani)
Control:- Sycamore and Plane trees should be planted where they receive good ...

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Common Name:- Sycamore Sooty Bark Disease
P_sycmrestybrk Sycamore Sooty Bark disease is caused by the fungus Cryptostroma corticale which is a relatively new disease (1945) to the UK. It prefers warmer climates and has been known on stored Maple logs under the bark and is also known as MAPLE Bark diseas...
Caused by:- The Fungus Cryptostroma corticale
Control:- There is no treatment, making Sooty Bark Disease impossible to prev...

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T
Common Name:- Take All Turf Disease
P_turfophptch Take-all is the same disease known as Turf Ophiobolus Patch disease, which is a fungal disease of lawns, particularly those with a high percentage of fine bent grasses (Agrostis spp.), which is a fine-leaved grass. It is caused by the fungus, Gaeu...
Caused by:- The Fungus Gaeumannomyces graminis
Control:- Grasses prefer a lower ph, down to a ph of 5, therefore avoid using...

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Common Name:- Tar Spot of Acer
P_trsptacer Tar Spot of Acer is a very conspicuous fungal leaf disease of sycamore and some other maples and is caused by the fungus Rhytisma acerinum.
There are several genetically distinct varieties of the fungus, which vary in the species of Acer t...
Caused by:- The Fungus Rhytisma acerinum
Control:- Preventative spraying in the spring, with a systemic fungicide, m...

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Common Name:- Tarsonemid Mites
P_stbymites There are several Tarsonemid Mites that attacks plants of many genus. Some are specific to a few plants, whilst some are more catholic in their choice of host and some are harmless to plants. They suck the sap from the plant causing death of the a...
Caused by:- Various Mites of the Tarsonemidae Family
Control:- A broad spectrum insecticide may cause more damage than a specific ...

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Common Name:- Thrips
P_thrips The Onion Thrips (Thrips tabaci) adult and nymph. Picture by Alton N. Sparks, Jr., University of Georgia, Bugwood.org.
There are over 5000 different Thrips of the Order Thysanoptera most are small slender insects with fringed wings and abo...
Caused by:- Insects of the Thysanoptera Order
Control:- There are several natural enemies such as <a href="/pests/269?telep...

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Common Name:- Thunderworms
P_thndrworm Thunderworm are long (20cm) thin (1mm) creamish worms that spends most of their lives in the soil. They are members of the genus Mermis and are in the Phylum Nematoda and their body contents can usually be seen through their translucent body.
Caused by:- Nematodes of the Mermis Genus
Control:- No control is necessary.

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Common Name:- Toadstools
P_toadstool Toadstools or mushrooms is caused by fungi and can develop all over the garden, wherever there is organic matter for it to decay. It is a natural part of the flora of any garden and most toadstools fungi are providing a useful service in recycling...
Caused by:- Various Fungi
Control:- Simply brush off the toadstools when they appear, to prevent them f...

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Common Name:- Tomato Blight
P_tomatoblight1 The blight is caused by a microscopic fungus Phytophthora infestans whose spores easily break away from infected leaves and is spread by the wind. This is the same fungus that causes Potato blight which eventually reaches the roots and tubers. It ...
Caused by:- The Fungus Phytoththora infectans
Control:- Tomato blight spreads by wind and water-splashes and is almost impo...

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Common Name:- Tomato Blotchy Ripening
P_tombltchripen Tomato Blotchy Ripening is a problem which is not fully understood, but environmental conditions, damage during fertilisiation and or thrips-transmitted Tomato spotted wilt virus seems to play a major part in its cause. The symptoms are yellow or...
Caused by:- Unknown, but probably Environmental Conditions
Control:- Environmental factors that are associated with this problem are fir...

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Common Name:- Tomato Cyst Eelworms
P_potcysteel Cysts of yellow potato cyst nematode Picture by Bonsak Hammeraas, Bioforsk - Norwegian Institute for Agricultural and Environmental Research, Bugwood.org.
The Tomato Cyst Eelworms are the same two eelworms that are known as Potato Cyst Eelwo...
Caused by:- Two Nematodes of the Heterodera Genus
Control:- Infestations of Potato Cyst Eelworm can be predicted by monitoring ...

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Common Name:- Tomato Fruit Splitting
P_tomftsplit Tomato Fruit Splitting, with inevitable secondary fungal infection of the fruit, is not a pest as such and is a physiological problem due mainly to erratic watering or large swings in temperatures between day and night. Another more rarer cause is...
Caused by:- Physiological Stress Problems
Control:- Mulching plants and ensuring regular watering should eliminate the ...

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Common Name:- Tomato Ghost Spot
P_tomghstspot Tomato Ghost Spot is caused by the fungus Botrytis which mainly happens when there is low temperatures and high humidity.
The symptoms are the green fruits gets whitish circular ...
Caused by:- The Fungus Botrytis cinerea
Control:- Ensure that there is good air circulation around the plants. This w...

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Common Name:- Tomato Greenback
P_tomgnback Tomato Greenback is probably a physiological problem which is exacerbated by the genetic make up of the tomato variety. The symptoms are that a large portion usually around the stalk end remains green and refuses to ripen, whilst the rest of the f...
Caused by:- Physicological Causes
Control:- Provide shade or external blinds or whitewash the greenhouse glass ...

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Common Name:- Tomato Leaf Mould
P_tomlfmld Tomato Leaf Mould is caused by the fungus Mycovellosiella fulva (formally Fulvia fulva or Cladosporium fulvum) which affects the foliage of tomatoes. The pathogen only affects tomatoes and and is usually a problem mainly in greenhouses, but can af...
Caused by:- The Fungus Mycovellosiella fulva
Control:- Use seed certified to be disease free or treat seed with the hot wa...

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Common Name:- Tomato Moth
P_tommoth The Tomato Moth Lacanobia oleracea (Polia oleracea and Melanchra oleracea) is also known as the Bright-line Brown-eye.
The Bright-line Brown-eye refers to a thin W shaped line on the trailing edge of the wings and a brown spot on the wings....
Caused by:- The Larvae of the Moth Lacanobia oleracea
Control:- If the infestation is light you can try and pick the caterpillar fr...

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Common Name:- Tomato Pith Necrosis
P_tomptnecr Tomato Pith Necrosis is caused by the soil-borne bacterium Pseudomonas corrugata which also attacks peppers and chrysanthemums. It tends to attack mature plants just before the tomato fruits ripens usually when the nights are cold compared with da...
Caused by:- The Bacterium Pseudomonas corrugata
Control:- Try to avoid low nigh-time temperatures, high nitrogen fertility a...

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Common Name:- Tomato Viruses
P_tomvirus Tomato Spotted Wilt Virus Picture by William M. Brown Jr., Bugwood.org.
There are many viruses that attack Tomato plants. Their symptoms are varied depending upon the variety of...
Caused by:- Various Viruses
Control:- Obtain seed from reputable sources that can guarantee virus free se...

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Common Name:- Tortrix Moths
P_carntortmoth The Carnation Tortrix Moth Cacoecimorpha pronubana Picture from Wikimedia Commons.
Tortrix Moths belong to the family Tortricidae which has over 9000 species and is commonly known as Tortrix Moths. They attack a wide range of plants...
Caused by:- Various Moths of the Tortricidae Family
Control:- The moths usually has at least two generations per year, between la...

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Common Name:- Tulip Fire
P_tlipfire Tulip fire is a fungal disease of tulips caused by Botrytis tulipae and is closely related to the grey mould pathogen Botrytis cinerea. It which produces brown spots on stems and twiste...
Caused by:- The Fungus Botrytis tulipae
Control:- Remove immediately any infected leaves and spray with fungicide the...

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Common Name:- Tulip Grey Bulb Rot
P_tlipgrblbrot Tulip Grey Bulb Rot is a fungal disease caused by Rhizoctonia tuliparum which is related to R. solani. It usually cause the bulb to rot before the shoot emerges from the soil.
Any bulbs that does shoot will produce severely distorted shoots...
Caused by:- The Fungus Rhizoctonia tuliparum
Control:- Use only bulbs certified to be disease free.<br /> Any affected bu...

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Common Name:- Turf Dollar Spot
P_trfdlrspot Turf Dollar spot is caused by the fungus Sclerotinia homoeocarpa, which experts in taxonomy think should be in another genus. Therefore this name may change in the future. This fungus blights leaf tissues but does not affect turf grass roots or cr...
Caused by:- The Fungus Sclerotinia homoeocarpa
Control:- Proper lawn management, such as spiking, proper watering and fert...

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Common Name:- Turf Fairy Rings
P_lnfryrng Fairy Rings are also known as fairy circle, elf circle, elf ring or pixie ring and also occupy a prominent place in European folklore as the location of gateways into elfin kingdoms, or places where elves gather and dance. It is a naturally occur...
Caused by:- Variuos Fungi
Control:- Fairy rings are rarely fatal to lawns.<br /> If fairy rings are no...

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Common Name:- Turf Ophiobolus Patch
P_turfophptch Turf Ophiobolus Patch disease now known as Take-all is a fungal disease of lawns, particularly those with a high percentage of fine bent grasses (Agrostis spp.), which is a fine-leaved grass. It is caused by the fungus, Gaeumannomyces graminis whi...
Caused by:- The Fungus Gaeumannomyces graminis
Control:- Grasses prefer a lower ph, down to a ph of 5, therefore avoid using...

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Common Name:- Turf Red Thread
P_tfredthrd Turf Red Thread disease is a fungal disease of lawns especially in lawns of low nitrogen along with conditions of high humidity or prolong wetness. It is caused by the fungus Laetisaria fuciformis (formerly Corticium fuciforme) and tends to appea...
Caused by:- The Fungus Laetisaria fuciformis
Control:- Fertilise your lawn with adequate amounts of fertiliser especially ...

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Common Name:- Turf Snow Mould
P_snowmld Turf Snow Mould fungi are active when the temperature is just above freezing and in moist conditions. These conditions occur most frequently under snow cover or anything else that covers the grass, such as fallen leaves.
Snow mould in grass...
Caused by:- Two Fungi Fusarium nivale or Typhula incarnata
Control:- The best way of preventing or reducing snow mould problems in lawns...

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Common Name:- Turnip Gall Weevil
P_tnpglwvl The Turnip Gall Weevil Ceuthorhynchus pleurostigma attacks turnips, but it also attacks other members of the brassica family such as cabbages, rape, cauliflower and mustard.
The feeding activities of the larvae of this weevil simulat...
Caused by:- The Weevil Ceuthorhynchus pleurostigma
Control:- This is a minor pest and can usually be ignored, but if is a proble...

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U
Common Name:- Urocystis
P_urocystis Urocystis is a genus of smut fungi belonging to the family Tilletiaceae which infect grasses and other plants. There are several species of this fungi and the symptoms of each differs according to plant or species. Some species of Urocystis are U...
Caused by:- A Genus of Smut Fungi
Control:- Crop rotations, planting resistant varieties of plants avoid sowing...

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Common Name:- Uromyces
P_uromyces Uromyces is a genus of fungal plant pathogens in the family Pucciniaceae. Many species causes rust in various plants. Some are specific to a particular plant species and others are omni-pathogenic.
Some species of Uromyces are U. apiosporus...
Caused by:- A Fungal Plant Pathogen
Control:- Various strategies depending on plant affected.

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V
Common Name:- Vapourer Moth
P_vprmoth The Vapourer Moth Orgyia antiqua, also known as the Tussock moth, feeds on a wide range of broad-leaved deciduous trees and shrubs, and can be very destructive in forests and cities. Some of the trees and shrubs attacked are Apple, Buddleia...
Caused by:- The Moth Orgyia antiqua
Control:- Hand picking off the females will cure light infestations.<br /> S...

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Common Name:- Verticillum Wilts
P_vertwilt Verticillium Wilt is a soil bourn disease caused by several species of Verticillium fungi, but two species Verticillium dahliae and V. albo-atrum are the most common. V.dahliae, which produce resting spores, is most prevalent in hardwood tr...
Caused by:- Various species of Verticillum Fungi
Control:- In confirmed cases remove and destroy the plant or tree with as m...

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Common Name:- Viburnum Beetle
P_vibrnmbtle The Viburnum Leaf Beetle, Pyrrhalta viburni whose larvae eats the leaf tissues between the leaf veins until it has a lace-like appearance. Damage is mainly concentrated on young shoots.
It is native to Europe and has been increasing ...
Caused by:- The Larvae and Adult Beetle Pyrrhalta viburni
Control:- With light infestation you can squash or pick off the larvae and ...

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Common Name:- Viburnum Cushion Scale
P_vibrnmcotscl The Viburnum Cushion Scale Lichtensia viburni live on the underside of the leaces next to a leaf vein where it sucks the sap from the leaf and excrete honeydew. This honeydew falls on the lower leaves where it may cause sooty mould to ddeve...
Caused by:- The Scale Insect Lichtensia viburni
Control:- Brushing of the insects with methylated spirits can be tried or if ...

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Common Name:- Viburnum Whitefly
P_vibrnmwhtfly The Viburnum Whitefly Aleurotrachelus jelinekii is a sap-sucking insect found on the underside of the leaves of Viburnum and sometimes on strawberry trees.
The white winged flies are 1-2mm long and can be usually be seen in mid-summe...
Caused by:- The insect Aleurotrachelus jelinekii
Control:- Spray the shrub thoroughly in mid summer when adult whiteflies begi...

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Common Name:- Vine Erinose Gall Mite
P_vineermite The Vine Erinose Mite Colomerus vitis of the family Eriophidae, is also known also as the grape erineum mite, grape gall mite, grape bud mite, grape blister mite, grape leaf blister mite, leaf roll mites, bud mites and blister mites.
...
Caused by:- The Gall Mite Colomerus vitis
Control:- Individual leaves can be picked off and burnt or destroyed to preve...

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Common Name:- Vine Weevil
P_vineweevil1 There are several species of Vine Weevils from the genus Otiorhynchus whose soil born larvae does great damage to a wide range of plants, shrubs and trees especially Azalea, Camellia, Cyclamen, Begonias Euonymus, Fuchsias, Impatiens, Primulas, Rho...
Caused by:- Several Beetles of the Genus Otiorhyncbus
Control:- They are difficult to control because of their nocturnal behaviour ...

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Common Name:- Violet Gall Midge
P_ violtglmdge There are three Violet Gall Midges Dasineura affinis, dasyneura violae and Phytophaga violicola.
Phytophaga violicola is found in the USA where the adult fly or midge lays white eggs in the curled margins of the new unfolded leaves....
Caused by:- Midges from the Genus Phytophaga and Dasineura
Control:- Cut off the distorted leaves or the whole plant as soon as you see ...

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Common Name:- Violet Root Rot
P_vletrtrot Violet root rot is caused by several Helicobasidium species that lives in the soil and all of which gives similar symptoms. Some of the species are H. brebisonii, H. mompa, H. purpreum and H. compactum. This fungus is world wide and different regi...
Caused by:- Several species of Helicobasidium Fungus
Control:- Remove infected plants before they start to disintegrate and produc...

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Common Name:- Viruses
P_virus Viruses are an ultra small intracellular parasite that can only be seen under an electron microscope. They come in many shapes and sizes. They have DNA covered in a protein coat and uses the cell host to reproduce its DNA to replicate itself. Plan...
Caused by:- Protien Coated DNA living organisms.
Control:- There is no cure for viruses and plants are best destroyed as soon ...

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Common Name:- Voles
P_voles There are about 155 species of Voles that can invade a garden, such as Arvicola amphibius:- the water vole, Clethrionomys glareolus:- the Bank vole, and Microtus agrestris:- the Orkney Vole.
It is a small rodent looking like a mouse, betwee...
Caused by:- Several Genus from the Cricetidae Family
Control:- Voles have predators such as Foxes, Weasels, Kestrels, Snakes, Owls...

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W
Common Name:- Walnut Blight
P_wlntblgth Walnut Blight is a bacterial blight caused by the bacteria Xanthomonas campestris pv. juglandis (Pseudomonas juglandis). It causes small brown angular to circular spots with yellow halos on leaflets which merge into large dry withered areas. It c...
Caused by:- The Bacteria Xanthomonas campestris pv. juglandis
Control:- Infected parts should be cut out to well below any visible damage...

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Common Name:- Walnut Blister Mite
P_wlntblstrmte The Walnut Blister Mite Eriophyes erinea is an eriophyid mite that feeds on the lower surface of leaves, causing a blister-like swellings on the upper surface of leaves.
On the underside of the leaf, beneath the blister, is a yellow...
Caused by:- The Mite Eriophyes erinea
Control:- Spraying with a systemic insecticide in late spring will kill the m...

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Common Name:- Walnut Leaf Blotch
P_wlntbltch Walnut Leaf Blotch is also known as Walnut Anthracnose and is caused by the fungus Marssonina juglandis, which fluctuates in severity from year to year, being most damaging in wet summers. It was formally known as Gnomonia leptostyla, or 'M...
Caused by:- The Fungus Marssonina juglandis
Control:- Fallen leaves from infected plants should be cleared and burnt or d...

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Common Name:- Wasps
P_wasps There are over 100,000 species of wasps most of which are parasitic to other insect pest species. Almost every pest insect species has at least one wasp species that preys upon it. This makes wasps extremely important in natural or biological cont...
Caused by:- Wasps from the Vespidae Family
Control:- Unless they are causing problems and their flight path is where peo...

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Common Name:- Water Lily Aphid
P_wtrlyaphid The Water Lily Aphid Rhopalosiphum nymphaeae is a brownish, pear shaped aphid about 2mm which lives in colonies on the upper surface of the lily leaves where they sucks the sap from the plant.
The aphids overwinter as eggs on Prunus species...
Caused by:- Thi Aphid Rhopalosiphum nymphaeae
Control:- Although many insecticides will kill these aphids, eradicating thes...

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Common Name:- Water Lily Beetle
P_wtrlybtle The Water Lily Beetle Galerucella nymphaeae and its larvae eat circular or elongated slots in the leaves of the lily. The adult beetles can cause significant damage to the flowers as well. This damage weakens the lily and secondary fungi often ent...
Caused by:- The Beetle Galerucella nymphaeae
Control:- Spraying with insecticides is difficult as these causes damage to f...

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Common Name:- Water Lily Leaf Spot
P_wtrlylfspot Water Lily Leaf Spot is caused by the fungus Ramularia nymphaearum, which causes reddish spots, sometimes with a distinctive yellow band around the edge, to appear above and below the leaves and on the stems. As it progresses small black fungal bo...
Caused by:- The Fungus Ramularia nymphaearum
Control:- Removing damaged foliage and burn and destroy.<br /> In ponds with...

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Common Name:- Waterlogging
P_waterlog Waterlogging is not a pest as such, but a physiological condition where the soil is saturated by water. It is one condition what kills more plants than any other conditions, both in house plants and in the garden. Most plants will withstand many d...
Caused by:- Too much water in soil
Control:- Improved soil by adding humus and corse sand to promote drainage an...

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Common Name:- Weedkillers
P_wdkiller Many gardeners seems to think that applying weedkillers is gardening. Looking at the shelvs at gardening centers and you will see rows and rows of weedkillers and only one with pest and disease chemicals. Rarely is there a need for weedkillers and...
Caused by:- Various Misuse of Weedkillers
Control:- Read the label and or instructions before using any weedkiller.<b...

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Common Name:- Weevils
P_vineweevil1 A weevil is a beetle belonging the Curculionoidea superfamily. They are usually small, less than 8 millimetres, and both larvae and adult usually eat a range of plants. There are over 60,000 species in several families, but most true weevils are i...
Caused by:- Beetles of the Curculionoidea superfamily
Control:- Spraying with insecticides and turning over the soil to expose the ...

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Common Name:- Western Flower Thrip
P_wfthrips The Western Flower Thrips (WFT), Frankliniella occidentalis can be a serious insect pest on over 500 different species of plants.
They are native to North America, but as they can hide in plant materials they have now spread worldwide.
Caused by:- The Thrip Frankliniella occidentalis
Control:- The thrips' natural enemies include insects of genus Orius and Ne...

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Common Name:- White Blister
P_whiblster White Blister caused by the fungus Albugo candida affects most plants of the Brassicaceae or Cruciferae family. Other species of Albugo affects other families like Compositae and Aizoaceae or Ficoidaceae.
This fungus is also related to the ...
Caused by:- The Fungus Albugo candida
Control:- Remove affected plant parts, and burn or dispose of severely infect...

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Common Name:- White Rust
P_whiterust White rust is a chronic foliar disease problem for several plants especially of the brassica. spinach and other plants. It is caused by the fungus Albugo candiada and there are several species in this Genus that tends to attack specific pl...
Caused by:- Fungus species of the Genus Albugo
Control:- To control Spinach White Rust fungicides need to be applied several...

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Common Name:- Whiteflies
P_cabbwhitefly There are over 1400 species of whitefly worldwide that attack a wide range of plants. Some species need warmth to proliferate and others, like the Cabbage whitefly, can live outdoors. The eggs are laid on the undersides of leaves and are cone-shap...
Caused by:- Small Sap Succking White Flies
Control:- Whitefly control can be difficult and complex as whiteflies readily...

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Common Name:- Willow Anthracnose
P_wllwanthnse Willow Anthracnose is caused by the fungus Marssonina salicicola, which has many synonyms such as:-
Xyloma sphaerioides Pers., Syn. meth. fung. (Göttingen) 1: 106 (1801)
Excipula sphaerioides (Pers.) Fr. [as 'sphaeroides'], Syst. myc...
Caused by:- The Fungus Marssonina salicicola
Control:- Raking up and destroying fallen diseased leaves, twigs and pruned o...

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Common Name:- Willow Bark Aphid
P_wlwbkaphid The willow Bark Aphid Tuberolachnus salignus is a very large aphid with black spots on its abdomen and three thorn-like projection on the back end of the abdomen. They are also called the Giant Bark Aphid and the Large or Giant Willow Aphid.
...
Caused by:- The Aphid Tuberolachnus salignus
Control:- Spraying with insecticides before the aphids become heavily establi...

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Common Name:- Willow Bean Gall Sawfly
P_wllowbngallsfly Several species of sawflies of the Pontania genera causes bean galls in willow leaves. Adults sawflies emerge in late spring and females lay eggs into the leaf tissue. This stimulates the formation of hard yellowish-green to red kidney shaped gall...
Caused by:- Several species of Pontania Sawflies
Control:- In general these galls do not do serious damage to the Willow and c...

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Common Name:- Willow Black Canker
P_willowblkcanker Willow Black Canker symptoms appear, after Willow Scab, in late spring to summer when red brown spots appear on the leaves which die and remain on the tree. Attack kills the young leaves and causes die-back and eventually cankers of the young sho...
Caused by:- The Fungus Glomerella(Phyalospora) miyabeana
Control:- Black Canker is spread by rain and wind activity, which disperses t...

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Common Name:- Willow Blight
P_willowblight Willow Blight is actually caused by two diseases, Willow Scab and Black Canker. They are caused by the fungi Glomerella miyabeana(Phyalospora miyabeana and Venturia saliciperda(Fusicladium saliciperdum) that share similar symptoms. Plants that are...
Caused by:- The Fungi Glomerella miyabeana & Venturia saliciperda
Control:- Pruning out diseased shoots and rake up fallen leaves and burn alon...

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Common Name:- Willow Flea Weevil
P_wllowfleaweevil Willow, bayleaf, cherries, plums, and poplar leaves may be severely damaged by these small insects from mid-summer on. Eventually the leaves blister, turn brown and drop off early in the autumn. Adults are tiny, elliptical, black weevils, about 3m...
Caused by:- The Weevil Isochnus(Rhynchaenus) rufipes
Control:- Spraying with a knock down insecticide in spring when the adults ar...

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Common Name:- Willow Leaf Beetles
P_wllowlfbeetle There are many beetles and their larvae that devour Willow (salix). The specific species is dependant on which species of Salix is grown and where in the world, but all the beetles and their larvae will attack Willow and other trees like Poplars. ...
Caused by:- Various Beetles
Control:- Spraying in spring and early summer might be the only option, but t...

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Common Name:- Willow Scab
P_willowscab Willow scab attacks and kills young leaves and causes die-back and eventually cankers of the young shoots . Olive-brown spores can be seen all along the veins on the undersides of leaves. It is caused by the fungus Venturia saliciperda(Fusicladium...
Caused by:- TheFungus Venturia(Fusicladium) saliciperda
Control:- Pruning out diseased shoots and rake up fallen leaves and burn alon...

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Common Name:- Willow Watermark Disease
P_wllowwtrmkdis This disease is caused by the Bacterium Brenneria salicis(formerly Erwinia salicis) and damages willow trees throughout the world. The disease is spreads rapidly in the wood vessels, which transport the water from the roots. In multiplying the bac...
Caused by:- The Bacteria Brenneria salicis
Control:- Very little can be done for infected trees apart from removal and b...

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Common Name:- Wilting
P_wilting There are many reasons why plants wilts or sags due to low turgor pressure in the plants cells. One of the most usual cause of wilting is overwatering. This causes the roots to get blocked by lack of oxygen or fungi and their roots begin to strugg...
Caused by:- Various causes
Control:- Depending on the cause the appropriate action can save a plant if i...

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Common Name:- Wind Damage
P_winddamage This Wild Rose which reaches a height of about twelve feet at the end of the garden was blown over and snapped in strong winds. Wind damage can come in many guises and are often attributed to other causes. On the worst side wind uproots trees and ...
Caused by:- The wind
Control:- Some trees and plants can be used as a wind break for more sensitiv...

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Common Name:- Winter Aconite Smut
P_winteraconitesmut On the deeply cleft palmate leaves and stems of Winter Aconite raised grey blisters develop. These sori like mass of spores later darken and erupt shedding black spores in the wind. This fungus needs actively growing leaves and stems to reproduce ...
Caused by:- Urocystis eranthidis
Control:- Spray unaffected plants with a systemic fungicide and remove infect...

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Common Name:- Winter Moth
P_wintermoth The Winter Moth is an unusual moth in that it is probably the only moth that is active in the winter in temperate climes. Their caterpillars eat holes in leaves, blossom and fruitlets which are often misshapen if they continue to develop. Apart fo...
Caused by:- The Moth Operophtera brumata
Control:- This pest can be reduced by placing a sticky grease band or sticky ...

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Common Name:- Wireworm
P_wireworm1 Wireworms are the soil dwelling grubs of the Click Beatles. There are about 60 types of Click Beatles in the UK, but only three are usually a pest on plant tubers like Dahlias and the roots of many plants like Chrysanthemums. The three types are ...
Caused by:- Larva of Click Beatles
Control:- There are no known safe chemical control of this pest. Crush any w...

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Common Name:- Wisteria Scale
P_wisteriascale1 Large scales appear when there are no leaves in the winter. When these are cracked open many white fluffy eggs fall out. Wisteria scale is a relatively new pest in Britain, which was first found in a London garden in 2001. Since then it has spread...
Caused by:- A species of Scale insect
Control:- Organic pesticides, such as those based on soft soaps or plant oils...

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Common Name:- Witches Broom
P_witchesbroom Witches broom is an abnormal growth of a many-branched structure and is commonly found on a large number number of species of trees, shrubs and soft plants such as cocoa, maple, Hornbeam, willow, conifers such as pine and spruce, honeysuckle, pota...
Caused by:- Various Fungi, bacteria and aphids
Control:- Human activity is often the cause of the introduction of these orga...

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Common Name:- Woodlice
P_woodlice Woodlice are crustaceans related to slaters, shrimps, lobsters and crabs, and belong to the arthropods order of Isopoda. They are the only crustaceans that have properly invaded land, without the need to return to water in order to breed, but they...
Caused by:- Several Genus and species of Crustaceans
Control:- The woodlice is preyed upon by a number of animals around the world...

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Common Name:- Wooly Aphids
P_woolyaphid1 Wooly Aphids are sucking insects that live on plant sap, and whose larvae produces a filamentous waxy white covering which resembles cotton wool and at first sight this may make them appear to be a fungus.
They have a wide range of host inc...
Caused by:- Various Insects and their larvae
Control:- The best way to tackle this pest is to blast off the fluffy, sticky...

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Common Name:- Wooly Vine Scale Insect
P_woolyvnescle This scale insect is common throughout the UK, Europe and America feeds on a wide range of woody plants. It occasionally attacks grapevine, peach and currants and survives by sucking the sap from the host tree or vine. The plant is weakened and so...
Caused by:- The Scale insect Pulvinaria vitis
Control:- A winter tar or oil wash when the plant is dormant will help to eli...

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Common Name:- Worms
P_earthworms Worms consists of many different distantly related animals which have a long wriggling cylindrical body and no legs. They are invertebrates and include Earthworms, Nematodes, Flatworms, insect larvae such as grubs, and maggots and some marine anim...
Caused by:- Several Genus and species
Control:- Always use compost on soils instead of chemicals where this is poss...

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X
Common Name:- X-Disease
P_xdisease X-DISEASE is caused by the bacterium Xylella fastidiosa that tends to live in the xylem of plants where it produces a gel which prevents nutrients transport. The symptoms vary according to the plant host. Strains of this bacterium are the causal a...
Caused by:- The Bacterium Xylella fastidiosa
Control:- If caught early enough the infected branch could be pruned below th...

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Y
Common Name:- Yellow Tail Moth
P_yllowtailmoth This is a pretty moth with a feathery look that attracts your attention in the gardens through Europe. It is also called Goldtail or Swan Moth The larvae or caterpillar feed on the leaves of many trees and sometimes perennials and are not usually ...
Caused by:- The Moth Euproctis similis
Control:- The moth can be picked off using gloves or sprayed with a propriety...

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Common Name:- Yellows Disease
P_yellows Yellows is a plant diseases that causes yellowing of the leaves and stunted growth. In diseased plants many membrane-bound structures resembling mycoplasma-like organisms are found within the phloem sieve elements through which nutrients and sugar...
Caused by:- Mycoplasma-like Organisms
Control:- There are no known cure and diseased plants are best removed and bu...

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Common Name:- Yucca Leaf Spot
P_yuccaleafspot1 Yucca suffers from a few fungi that causes leaf spot. They include Cylindrosporium angustifolium, Coniothyrium Concentricum and Cercospora concentrica. Cylindrosporium angustifolium spots are about 12 to 20mm oval, yellowish brown with a darker b...
Caused by:- Various Fungi
Control:- The disease is spread by splashes from other leaves and spores from...

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Z
Common Name:- Zucchini Yellow Mosiac Virus
P_zucyellmosiacvir1 Zucchini Yellow Mosaic virus(ZYMV) is one of the most economically important viruses and can infect pumpkin, squash, summer squash, melon, watermelon, other cucurbits plants. Symptoms. This disease stunts the plants and causes the leaves to have a...
Caused by:- A Mosiac virus
Control:- The first thing is to only use seed sourced from a reputable source...

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