文章
Dummer. ゛☀
2017年09月17日
Many ornamental trees and shrubs are susceptible to Phytophthora root rot and can develop root and crown rot, particularly if the soil around the base of the plant remains wet for long periods of time. Typical symptoms of a root disease are apparent on infected plants. The leaves will appear droughtstressed and may die quickly as the weather warms in late spring or early summer. Trees that are especially susceptible include oak and dogwood.
Symptoms and Diagnosis
Leaves will appear drought stressed, sometimes turning dull green, yellow, red, or purple as they wilt. Infected trees may survive a few years before the disease kills the whole plant. The bark around the soil-line may appear darkened. Cutting away some bark should reveal red-brown discoloration in the wood underneath it. Disease symptoms are distinguishable from Armillaria root rot because mycelial mats do not develop in tissues infected with Phytophthora root rot.
Life Cycle
Root rot-causing Phytophthora species can survive in the soil for years, as long as moist conditions persist. It can spread through splashing rain, irrigation water, and runoff water. Disease fungi can spread through contaminated soil and garden equipment as well. Rot is more likely to spread in early spring and late fall during cool, rainy weather. But symptoms are more likely during stress periods of low rainfall. Flooded and saturated soil conditions for 6–8 hours are especially conducive to the spread of root rots. Wounds are not required for infection.
Integrated Pest Management Strategies
1. Improve water drainage. Prior to planting, make amendments to the soil composition to help manage drainage away from tree roots. Don’t allow water to pool around the collar or root system. Core aerate to improve drainage and lessen compaction.
2. Raise the planting site to avoid poor drainage and prevent pools of standing water from forming around valuable ornamentals. Plant on mounds of soil. Never plant trees deeper than they were planted at the nursery.
3. Separate plants, shrubs, and trees according to their irrigation needs, and avoid overwatering.
4. Remove soil. If soil has been piled up over the crown, remove it carefully to expose root flare. This is where fungal infection is likely to occur.
5. Plant resistant or less susceptible varieties. Consider replanting with tolerant plants after Phytophthora root rot has been diagnosed. Trees that are tolerant to Phytophthora root rot include white cedar and American arborvitae.
Symptoms and Diagnosis
Leaves will appear drought stressed, sometimes turning dull green, yellow, red, or purple as they wilt. Infected trees may survive a few years before the disease kills the whole plant. The bark around the soil-line may appear darkened. Cutting away some bark should reveal red-brown discoloration in the wood underneath it. Disease symptoms are distinguishable from Armillaria root rot because mycelial mats do not develop in tissues infected with Phytophthora root rot.
Life Cycle
Root rot-causing Phytophthora species can survive in the soil for years, as long as moist conditions persist. It can spread through splashing rain, irrigation water, and runoff water. Disease fungi can spread through contaminated soil and garden equipment as well. Rot is more likely to spread in early spring and late fall during cool, rainy weather. But symptoms are more likely during stress periods of low rainfall. Flooded and saturated soil conditions for 6–8 hours are especially conducive to the spread of root rots. Wounds are not required for infection.
Integrated Pest Management Strategies
1. Improve water drainage. Prior to planting, make amendments to the soil composition to help manage drainage away from tree roots. Don’t allow water to pool around the collar or root system. Core aerate to improve drainage and lessen compaction.
2. Raise the planting site to avoid poor drainage and prevent pools of standing water from forming around valuable ornamentals. Plant on mounds of soil. Never plant trees deeper than they were planted at the nursery.
3. Separate plants, shrubs, and trees according to their irrigation needs, and avoid overwatering.
4. Remove soil. If soil has been piled up over the crown, remove it carefully to expose root flare. This is where fungal infection is likely to occur.
5. Plant resistant or less susceptible varieties. Consider replanting with tolerant plants after Phytophthora root rot has been diagnosed. Trees that are tolerant to Phytophthora root rot include white cedar and American arborvitae.
0
0
文章
Dummer. ゛☀
2017年09月17日
Gummosis is the oozing of sap from wounds or cankers on fruit trees. Gummosis can result from environmental stress, mechanical injury, or disease and insect infestation. Cytospora canker or Valsa canker, the fungal cause of gummosis, affects stone fruit trees like apricot, cherry, peach, and plum. Cytospora infection is distinguishable from insect damage and mechanical injuries because sawdust or pieces of bark are not mixed in the sap, as it would be with insect or mechanical damage. Cytospora canker is also known as perennial canker.
Symptoms and Diagnosis
On trees infected with Cytospora canker, new shoots or leaves may turn yellow or wilt. Sunken lesions develop on the bark. These lesions enlarge, and gummy, amber-colored sap oozes from the bark. Curly orange threads (fungal chains) may grow out of the bark as the disease progresses. Leaves may brown and drop. The disease kills the wood underneath the cankers, often causing whole branches to die. Infected wood and the defoliation that may occur weakens the tree, but if the disease infects the trunk, the whole tree may die.
Life Cycle
Cytospora canker is caused by one of two different fungi. The fungus overwinters on dead wood or in sunken lesions. Curly orange fungal chains will release spores in the spring which are distributed by winds and rain splash. Once the spores land on a host tree, they enter through wounds made from insect boring, mechanical injuries, or winter injury. Symptoms are more prevalent during warm (70–85 degrees F), wet spring weather as the moisture facilitates entry into wounds. Trees just coming out of dormancy are most susceptible to the pathogen.
Integrated Pest Management Strategies
1. Be careful not to damage trunks with lawn mowers or other yard and garden equipment. Fungal spores enter the tree through injured tissue where they germinate and penetrate the tissue. This is the primary mode of infection.
2. Take steps to prevent winter injuries. Plant in well-drained soils or amend soils to improve drainage as needed. Avoid planting in open or windy areas to reduce desiccation. Select winterhardy cultivars matched to your hardiness zone. Paint the lower branches and trunks of 1–3 year old trees with white latex paint to reduce cold damage.
3. Proper care and maintenance. Prevent insect boring damage by maintaining the health of the tree. Prune and dispose of diseased branches in late winter. Burn infected wood, if possible.
4. Plant more resistant varieties. None of these are immune, but fungal development is slower if the disease becomes established.
Symptoms and Diagnosis
On trees infected with Cytospora canker, new shoots or leaves may turn yellow or wilt. Sunken lesions develop on the bark. These lesions enlarge, and gummy, amber-colored sap oozes from the bark. Curly orange threads (fungal chains) may grow out of the bark as the disease progresses. Leaves may brown and drop. The disease kills the wood underneath the cankers, often causing whole branches to die. Infected wood and the defoliation that may occur weakens the tree, but if the disease infects the trunk, the whole tree may die.
Life Cycle
Cytospora canker is caused by one of two different fungi. The fungus overwinters on dead wood or in sunken lesions. Curly orange fungal chains will release spores in the spring which are distributed by winds and rain splash. Once the spores land on a host tree, they enter through wounds made from insect boring, mechanical injuries, or winter injury. Symptoms are more prevalent during warm (70–85 degrees F), wet spring weather as the moisture facilitates entry into wounds. Trees just coming out of dormancy are most susceptible to the pathogen.
Integrated Pest Management Strategies
1. Be careful not to damage trunks with lawn mowers or other yard and garden equipment. Fungal spores enter the tree through injured tissue where they germinate and penetrate the tissue. This is the primary mode of infection.
2. Take steps to prevent winter injuries. Plant in well-drained soils or amend soils to improve drainage as needed. Avoid planting in open or windy areas to reduce desiccation. Select winterhardy cultivars matched to your hardiness zone. Paint the lower branches and trunks of 1–3 year old trees with white latex paint to reduce cold damage.
3. Proper care and maintenance. Prevent insect boring damage by maintaining the health of the tree. Prune and dispose of diseased branches in late winter. Burn infected wood, if possible.
4. Plant more resistant varieties. None of these are immune, but fungal development is slower if the disease becomes established.
0
0
文章
Dummer. ゛☀
2017年09月17日
Black knot is a name used to describe a disease of woody stems with black, knotty, outgrowths. It is most widespread on plum and cherry trees, but also infects apricots and peaches. Infection occurs in the spring, but symptoms of the disease may not be obvious until the following spring or even in later seasons.
Symptoms and Diagnosis
Initially the bark of infected twigs and medium-sized branches will begin to crack in the springtime. A light yellow discoloration and cork-like swelling occurs on infected areas. Knotted areas later turn an olive-green color and finally turn black and harden during the summer. The swelling weakens branches and may stunt or kill smaller branches due to decreased water and nutrient flow.
Life Cycle
Dibotryon morbosum is the fungus responsible for causing black knot disease on cherries and plums. Spores overwinter in the blackened "knots" of infected branches. Disease spores are spread to new hosts by wind during warm spring weather when temperatures are between 55–75 degrees F and there is rain or high humidity. Trees are weakened because the knots disrupt the normal flow of water and nutrients throughout the branches. Twig dieback is common.
Integrated Pest Management Strategies
1. Plant resistant varieties. Plums such as ‘President’, ‘Santa Rosa’, or ‘Fellinberg’.
2. Prune and destroy all knotted branches in the winter or before March 1. Prune 3–4 inches below the knot to remove all fungal material. Dip tools in a solution of 1–part bleach and 9–parts water between cuts.
3. Remove any wild cherry and plum trees surrounding your property. These trees may be harboring black knot and it spreads easily to cultivated varieties. Pruned material should be disposed of or burned.
4. Apply a fungicide cover spray at bud break. Pesticides registered for use include copper, chlorothalonil (Daconil), mancozeb, and thiophanate methyl (Cleary 3336).
Symptoms and Diagnosis
Initially the bark of infected twigs and medium-sized branches will begin to crack in the springtime. A light yellow discoloration and cork-like swelling occurs on infected areas. Knotted areas later turn an olive-green color and finally turn black and harden during the summer. The swelling weakens branches and may stunt or kill smaller branches due to decreased water and nutrient flow.
Life Cycle
Dibotryon morbosum is the fungus responsible for causing black knot disease on cherries and plums. Spores overwinter in the blackened "knots" of infected branches. Disease spores are spread to new hosts by wind during warm spring weather when temperatures are between 55–75 degrees F and there is rain or high humidity. Trees are weakened because the knots disrupt the normal flow of water and nutrients throughout the branches. Twig dieback is common.
Integrated Pest Management Strategies
1. Plant resistant varieties. Plums such as ‘President’, ‘Santa Rosa’, or ‘Fellinberg’.
2. Prune and destroy all knotted branches in the winter or before March 1. Prune 3–4 inches below the knot to remove all fungal material. Dip tools in a solution of 1–part bleach and 9–parts water between cuts.
3. Remove any wild cherry and plum trees surrounding your property. These trees may be harboring black knot and it spreads easily to cultivated varieties. Pruned material should be disposed of or burned.
4. Apply a fungicide cover spray at bud break. Pesticides registered for use include copper, chlorothalonil (Daconil), mancozeb, and thiophanate methyl (Cleary 3336).
0
0
文章
Dummer. ゛☀
2017年09月17日
The fungus, Armillaria mellea, occurs sporadically in this region and has been reported to infect over 25 species of ornamental trees and shrubs. The most distinctive sign of Armillaria infection is the honeycolored mushroom that grows from the roots and base of plants. The fungus is especially prevalent on oak but also affects many different kinds of fruit and nut trees, ornamentals, and herbaceous plantings. It is often referred to as oak root rot fungus because it is commonly found on oaks or in areas where oaks trees once were grown, such as cleared forest land.
Symptoms and Diagnosis
The symptoms of Armillaria are similar to those of other root disorders; height growth is reduced, foliage is sparse, and leaves that remain on plants are stunted and yellow. An abnormal flow of sap may be visible on the root collar. When soil is removed from the base of the trunk, black, root-like strands are visible and attached to larger roots. White to dark, fan-shaped mats of fungal strands develop between the bark and wood in infected root and trunk tissues. The most positive sign of infection is the production of clusters of honey-colored mushrooms at the base of the tree near the soil line. The mushrooms may have stalks 4 to 6 inches high with caps 1 inch high and 2 to 4 inches wide.
Life Cycle
Armillaria is found in the soil sporadically throughout the Midwest. The fungus spreads primarily by root-to-root contact or by root-like fungal strands. Root-like fungal strands grow through the soil and adhere to the host roots or root collar that it encounters. Successfully attacked trees do not die until infections girdle the base of the tree. On healthy, vigorous trees, Armillaria is not lethal but if present, it may begin to grow when the tree dies of other causes. Young trees are more likely to be killed by Armillaria. Trees that are 15–20 years old are more tolerant to attack.
Integrated Pest Management Strategies
1. Remove and destroy infected material. Remove as much of the stump as possible. Sterilize tools with a solution of 1–part bleach with 9–parts water after use.
2. Provide adequate moisture in a well-drained soil to maintain vigor and resistance to infection. Plants suffering from drought are extremely susceptible to infection. Fertilize trees appropriately in late winter or early spring.
3. No effective chemical controls are known. Plants reported by Auburn University to be resistant to Armillaria root rot include ginkgo, tulip tree, ash, bald cypress, cherry, Chinese elm, Chinese pistache, crabapple, cryptomeria, dawn redwood, eucalyptus, hackberry, holly, incense cedar, Leyland cypress, maidenhair tree, maple, privet, smoke tree, sweetgum, tree-ofheaven, white fir, and wisteria. These should be considered for replacement of diseased trees. New soil should be used to amend the planting site. All diseased material and associated roots, as much as possible, should be excavated before replanting.
Symptoms and Diagnosis
The symptoms of Armillaria are similar to those of other root disorders; height growth is reduced, foliage is sparse, and leaves that remain on plants are stunted and yellow. An abnormal flow of sap may be visible on the root collar. When soil is removed from the base of the trunk, black, root-like strands are visible and attached to larger roots. White to dark, fan-shaped mats of fungal strands develop between the bark and wood in infected root and trunk tissues. The most positive sign of infection is the production of clusters of honey-colored mushrooms at the base of the tree near the soil line. The mushrooms may have stalks 4 to 6 inches high with caps 1 inch high and 2 to 4 inches wide.
Life Cycle
Armillaria is found in the soil sporadically throughout the Midwest. The fungus spreads primarily by root-to-root contact or by root-like fungal strands. Root-like fungal strands grow through the soil and adhere to the host roots or root collar that it encounters. Successfully attacked trees do not die until infections girdle the base of the tree. On healthy, vigorous trees, Armillaria is not lethal but if present, it may begin to grow when the tree dies of other causes. Young trees are more likely to be killed by Armillaria. Trees that are 15–20 years old are more tolerant to attack.
Integrated Pest Management Strategies
1. Remove and destroy infected material. Remove as much of the stump as possible. Sterilize tools with a solution of 1–part bleach with 9–parts water after use.
2. Provide adequate moisture in a well-drained soil to maintain vigor and resistance to infection. Plants suffering from drought are extremely susceptible to infection. Fertilize trees appropriately in late winter or early spring.
3. No effective chemical controls are known. Plants reported by Auburn University to be resistant to Armillaria root rot include ginkgo, tulip tree, ash, bald cypress, cherry, Chinese elm, Chinese pistache, crabapple, cryptomeria, dawn redwood, eucalyptus, hackberry, holly, incense cedar, Leyland cypress, maidenhair tree, maple, privet, smoke tree, sweetgum, tree-ofheaven, white fir, and wisteria. These should be considered for replacement of diseased trees. New soil should be used to amend the planting site. All diseased material and associated roots, as much as possible, should be excavated before replanting.
0
0
文章
Dummer. ゛☀
2017年09月15日
Oriental chestnut gall wasp (OCGW) was discovered for the first time in the UK in a woodland in Kent, England, in June 2015. A second site was later confirmed with OCGW present in a small number of trees in a single street in St Albans, Hertfordshire.
Working with site owners and our partners in government, we took swift and appropriate action to reduce the population, and the risk of spread, as much as possible. We conducted surveys around the country for evidence of any other outbreaks, but found none.
Then follow-up surveying in summer 2016 found OCGW at several places in London and South-East England. The survey was mounted to find out whether OCGW was present at other locations than those found in 2015, and in compliance with our Protected Zone status for the species. (See 'Regulations and Powers' below.)
dentification and symptoms
OCGW is an insect of Asian origin which affects sweet chestnut trees in the Castanea family of trees. The only species of the Castanea family grown in significant numbers in Britain is the European sweet chestnut (Castanea sativa).
It is a pest of sweet chestnut trees because activity by its larvae (the 'grubs', or immature life stage) causes abnormal growths, called galls, to form on the buds, leaves, and petioles (leaf stalks).
The presence of these galls is the most obvious symptom of OCGW infestation.
The galls can be either green, rose-coloured, or red. They gradually dry out and turn brown and woody over the summer, when the adult wasps emerge from them, and they can cause the leaves to drop early. Most galls fall off the tree when the leaves fall, although galls attached to the bases of petioles (leaf stalks) can stay on the tree for some years.
Galls can grow up to 4cm (1.75in) in diameter, although most of those seen in England have been between 1cm and 2cm.
They can occur at any height on the tree, and on any age of tree with buds.
No other organism is knoRose-coloured call caused by oriental chestnut gall wasp (Dryocosmus kuriphilus) on sweet chestnut (Castanea sativa) leaf stalkwn to cause galls on sweet chestnut trees, so their presence is a reliable indicator of OCGW infestation.
The adult wasp is tiny, being only 2.5-3mm long, with a black body, translucent wings and orange legs. It emerges in June and July, but its small size mean it is unlikely to be seen by most visitors to affected sites.
Treatment
Control options include insecticide treatment. However, insecticide treatment of widespread outbreaks in the wider environment is unlikely to be effective because the galls encase the larvae, protecting them from chemical treatments.
An option in localised outbreaks is to conventionally harvest affected trees by felling or coppicing them and burning, deeply burying or mulching the lop and top (branches and tree-top material). Mulching (grinding the material into small fragments to destroy the pest) was used at Farningham Woods. The timber from the trunks can then be used in a bio-secure manner, e.g. for fencing.
Lifecycle
The female wasp lays eggs in the trees’ growth buds during the summer, and the eggs hatch within 30 to 40 days. The early stages of the larvae then lie dormant in the bud over the winter.
Oriental chestnut - gall wasp damageLarval activity resumes the following spring, and this activity causes the formation of galls, inside which the larvae develop, in early summer. The galls are formed on young twigs, on leaf petioles (stalks) or on the midrib of leaves. These green, red or rose-coloured galls start at approximately 5–20 mm in diameter, and can develop up to 4cm in diameter as the leaf tries to form.
Adult wasps emerge during June and July, leaving exit holes in the galls. The galls turn brown and woody over time, and can remain on the tree for two years or more.
Working with site owners and our partners in government, we took swift and appropriate action to reduce the population, and the risk of spread, as much as possible. We conducted surveys around the country for evidence of any other outbreaks, but found none.
Then follow-up surveying in summer 2016 found OCGW at several places in London and South-East England. The survey was mounted to find out whether OCGW was present at other locations than those found in 2015, and in compliance with our Protected Zone status for the species. (See 'Regulations and Powers' below.)
dentification and symptoms
OCGW is an insect of Asian origin which affects sweet chestnut trees in the Castanea family of trees. The only species of the Castanea family grown in significant numbers in Britain is the European sweet chestnut (Castanea sativa).
It is a pest of sweet chestnut trees because activity by its larvae (the 'grubs', or immature life stage) causes abnormal growths, called galls, to form on the buds, leaves, and petioles (leaf stalks).
The presence of these galls is the most obvious symptom of OCGW infestation.
The galls can be either green, rose-coloured, or red. They gradually dry out and turn brown and woody over the summer, when the adult wasps emerge from them, and they can cause the leaves to drop early. Most galls fall off the tree when the leaves fall, although galls attached to the bases of petioles (leaf stalks) can stay on the tree for some years.
Galls can grow up to 4cm (1.75in) in diameter, although most of those seen in England have been between 1cm and 2cm.
They can occur at any height on the tree, and on any age of tree with buds.
No other organism is knoRose-coloured call caused by oriental chestnut gall wasp (Dryocosmus kuriphilus) on sweet chestnut (Castanea sativa) leaf stalkwn to cause galls on sweet chestnut trees, so their presence is a reliable indicator of OCGW infestation.
The adult wasp is tiny, being only 2.5-3mm long, with a black body, translucent wings and orange legs. It emerges in June and July, but its small size mean it is unlikely to be seen by most visitors to affected sites.
Treatment
Control options include insecticide treatment. However, insecticide treatment of widespread outbreaks in the wider environment is unlikely to be effective because the galls encase the larvae, protecting them from chemical treatments.
An option in localised outbreaks is to conventionally harvest affected trees by felling or coppicing them and burning, deeply burying or mulching the lop and top (branches and tree-top material). Mulching (grinding the material into small fragments to destroy the pest) was used at Farningham Woods. The timber from the trunks can then be used in a bio-secure manner, e.g. for fencing.
Lifecycle
The female wasp lays eggs in the trees’ growth buds during the summer, and the eggs hatch within 30 to 40 days. The early stages of the larvae then lie dormant in the bud over the winter.
Oriental chestnut - gall wasp damageLarval activity resumes the following spring, and this activity causes the formation of galls, inside which the larvae develop, in early summer. The galls are formed on young twigs, on leaf petioles (stalks) or on the midrib of leaves. These green, red or rose-coloured galls start at approximately 5–20 mm in diameter, and can develop up to 4cm in diameter as the leaf tries to form.
Adult wasps emerge during June and July, leaving exit holes in the galls. The galls turn brown and woody over time, and can remain on the tree for two years or more.
0
0
文章
Dummer. ゛☀
2017年09月15日
Horse chestnut leaf miner (Cameraria ohridella) is an exotic insect pest which lives in horse chestnut trees. It was first reported in the UK in 2002, in the London Borough of Wimbledon, and has since spread north, south and west to most of England and parts of Wales, and there has been one confirmed sighting in Scotland.
Its larvae (caterpillars) mine within the leaves, and at high population densities they can destroy most of the leaf tissues. Although it can cause severe damage to horse chestnut leaves on an annual basis, and discolouration and defoliation before normal autumn leaf-fall, on its own the pest does not significantly impair trees' health, and they will usually flush normally the following spring.
However, it is possible that differences in climate, or interactions with other pests and diseases, might lead to greater impact in the UK. Consequently, the effects of the moth and its interaction with other pests and diseases, especially bleeding canker of horse chestnut, is being studied through the long-term monitoring of more than 300 chestnut trees at several sites in southern England. These trees are assessed twice each year for infestation, disease crown condition, growth and signs of dieback.
Origins
Horse chestnut leaf miner was first observed in Macedonia, in northern Greece, in 1985, and was described as a new species in 1986. In 1989, it appeared unexpectedly in Austria, and since then it has spread throughout central and eastern Europe. It was first found in Great Britain in 2002 in the London Borough of Wimbledon.
Spread
Dispersal of the moth from infested areas occurs on a broad front through adult flight, assisted by the wind, and through the passive transport of adult moths or infested leaves in or on vehicles. Transportation by vehicles appears to be responsible for the sudden appearance of the moth in towns and cities a long way from known areas of infestation.
Distribution
The map shows areas where confirmed sightings of horse chestnut leaf miner had been reported up to 2014.
Forest Research scientists are conducting a long-term study to determine whether there are any interactions of Horse chestnut leaf miner and the bacterum P. syringae pv. aesculi , which causes bleeding canker of horse chestnut, including whether one influences the extent of the other, and how they affect the health of affected trees. A paper reporting the results of the first 10 years of the study was published in the journal Agricultural and Forest Entomology.
Treatment
Damage can be reduced by removing fallen leaves during the autumn and winter and either composting them thoroughly, to destroy the over-wintering pupae, or if the leaves are collected into smaller heaps, by covering them with a layer of soil or other plant material to prevent adult emergence the following spring.
Its larvae (caterpillars) mine within the leaves, and at high population densities they can destroy most of the leaf tissues. Although it can cause severe damage to horse chestnut leaves on an annual basis, and discolouration and defoliation before normal autumn leaf-fall, on its own the pest does not significantly impair trees' health, and they will usually flush normally the following spring.
However, it is possible that differences in climate, or interactions with other pests and diseases, might lead to greater impact in the UK. Consequently, the effects of the moth and its interaction with other pests and diseases, especially bleeding canker of horse chestnut, is being studied through the long-term monitoring of more than 300 chestnut trees at several sites in southern England. These trees are assessed twice each year for infestation, disease crown condition, growth and signs of dieback.
Origins
Horse chestnut leaf miner was first observed in Macedonia, in northern Greece, in 1985, and was described as a new species in 1986. In 1989, it appeared unexpectedly in Austria, and since then it has spread throughout central and eastern Europe. It was first found in Great Britain in 2002 in the London Borough of Wimbledon.
Spread
Dispersal of the moth from infested areas occurs on a broad front through adult flight, assisted by the wind, and through the passive transport of adult moths or infested leaves in or on vehicles. Transportation by vehicles appears to be responsible for the sudden appearance of the moth in towns and cities a long way from known areas of infestation.
Distribution
The map shows areas where confirmed sightings of horse chestnut leaf miner had been reported up to 2014.
Forest Research scientists are conducting a long-term study to determine whether there are any interactions of Horse chestnut leaf miner and the bacterum P. syringae pv. aesculi , which causes bleeding canker of horse chestnut, including whether one influences the extent of the other, and how they affect the health of affected trees. A paper reporting the results of the first 10 years of the study was published in the journal Agricultural and Forest Entomology.
Treatment
Damage can be reduced by removing fallen leaves during the autumn and winter and either composting them thoroughly, to destroy the over-wintering pupae, or if the leaves are collected into smaller heaps, by covering them with a layer of soil or other plant material to prevent adult emergence the following spring.
0
0
文章
Dummer. ゛☀
2017年09月15日
The great spruce bark beetle (Dendroctonus micans) is found in forests throughout mainland Europe. It damages spruce trees by tunnelling into the bark of the living trees to lay its eggs under the bark, and the developing larvae feed on the inner woody layers. This weakens, and in some cases can kill, the tree. 
Outbreak stage
The beetle was first discovered in Great Britain in 1982 after it was accidentally introduced, most likely via a consignment of imported timber. It has become an established pest in Wales and western England, and has more recently expanded its range to southern Scotland.
Impact
The rate and extent of damage to individual trees and forests is variable. Neither the beetle nor its larvae burrow into the wood itself and, consequently, provided the wood is salvaged before the tree is completely dead, the timber is not spoiled in any way. Trees are killed by being completely girdled, at one or more points along the stem, although this may take several years of sustained attack. However, large breeding populations can be building up long before individual trees are killed, creating a risk of spread to adjacent and nearby trees.
Susceptible species
The beetle attacks and breeds in all species of spruce grown in Britain.
Symptoms
Look out for signs of poor tree health. Check especially for isolated or small groups of dead or dying trees characterised by browning foliage over some or all of the crown.
The entry of female beetles into the bark of trees gives rise to characteristic ‘resin tubes’ on the trunk. Resin tubes and granular resin at the base of the tree are reliable signs of stem or root attack. Resin tubes vary in colour from white and cream, to shades of purple and brown. They may be accompanied by copious resin bleeds. Loose bark with exposed beetle galleries usually indicates older infestations that have been attacked by woodpeckers.
Inspect the bark around resin tubes, particularly those that are purple to brown. A hollow sound when the bark is tapped often indicates successful attack. Remove the bark carefully and inspect for signs of the beetle. The most characteristic indicator is the presence of a mixture of insect faeces (frass) and bark packed into ‘islands’ creating a quilted appearance. All beetle stages, from egg to adult, might be present.
The beetle has a long life cycle, ranging from 12–18 months under British conditions. This results in extensive overlap of generations so that it is possible to find any stage at any time of year. However, there are periods, particularly in the winter, where most can be at the same stage.
Adult beetles are 6–8 mm long and 2.5–3 mm wide.They are black when mature, with a covering of orange hairs. The large size of the beetle enables the females to withstand the resin flow produced when they bore into the bark of trees.
Eggs are laid within a small egg chamber in the cambium of the tree. Each female can produce up to 300 eggs, laid in groups of 50–80, in interconnecting chambers. Eggs are usually laid on one side of the chamber.
Larvae - The beetle has five larval stages (instars), which each become progressively larger. All larval stages feed under the bark in a similar manner: larvae feed side-by-side, packing powdery wood debris (or ‘frass’) and diseased or dead larvae behind them into islands away from the main feeding site. The mixture of resin and frass forms a distinctive quilted pattern.
Pupae are the immobile, resting stage of beetle development before the larvae moult to the adult stage. Pupae are found in pupal cells among the larval frass. They are often found in close proximity and give rise, upon emergence, to aggregations of adults under the bark. These stages can be prolonged over several weeks or months, depending on temperature.
The newly emerged adults are light brown. As they mature the colour darkens to brown and black. Adult beetles move within and between trees mainly by crawling (at temperatures of 12°C or greater), but they occasionally fly (at temperatures of 22.5°C or greater).
Treatment
Information on treating infected trees can be found in the guidance document Minimising the impact of the great spruce bark beetle
Action
Statutory controls against the spread of D. micans were first put in place in Great Britain in 1982. Following the discovery of three new outbreaks outside the main infested area, the Forestry Commission reviewed the controls and consulted the forestry industry on two options: extension of the designation of the infested area and continuing the policy of movement restrictions into Scotland and north-east England, or revocation of our EU protected-zone status. The second of these options was agreed, and from 15 May 2005 the movement within Great Britain of conifer wood and conifer bark was no longer subject to any treatment requirements.
Part of the west of Scotland is designated as a ‘pest-free area’ out of which wood and bark can be moved without treatment under the EU plant passport regime.
Outbreak stage
The beetle was first discovered in Great Britain in 1982 after it was accidentally introduced, most likely via a consignment of imported timber. It has become an established pest in Wales and western England, and has more recently expanded its range to southern Scotland.
Impact
The rate and extent of damage to individual trees and forests is variable. Neither the beetle nor its larvae burrow into the wood itself and, consequently, provided the wood is salvaged before the tree is completely dead, the timber is not spoiled in any way. Trees are killed by being completely girdled, at one or more points along the stem, although this may take several years of sustained attack. However, large breeding populations can be building up long before individual trees are killed, creating a risk of spread to adjacent and nearby trees.
Susceptible species
The beetle attacks and breeds in all species of spruce grown in Britain.
Symptoms
Look out for signs of poor tree health. Check especially for isolated or small groups of dead or dying trees characterised by browning foliage over some or all of the crown.
The entry of female beetles into the bark of trees gives rise to characteristic ‘resin tubes’ on the trunk. Resin tubes and granular resin at the base of the tree are reliable signs of stem or root attack. Resin tubes vary in colour from white and cream, to shades of purple and brown. They may be accompanied by copious resin bleeds. Loose bark with exposed beetle galleries usually indicates older infestations that have been attacked by woodpeckers.
Inspect the bark around resin tubes, particularly those that are purple to brown. A hollow sound when the bark is tapped often indicates successful attack. Remove the bark carefully and inspect for signs of the beetle. The most characteristic indicator is the presence of a mixture of insect faeces (frass) and bark packed into ‘islands’ creating a quilted appearance. All beetle stages, from egg to adult, might be present.
The beetle has a long life cycle, ranging from 12–18 months under British conditions. This results in extensive overlap of generations so that it is possible to find any stage at any time of year. However, there are periods, particularly in the winter, where most can be at the same stage.
Adult beetles are 6–8 mm long and 2.5–3 mm wide.They are black when mature, with a covering of orange hairs. The large size of the beetle enables the females to withstand the resin flow produced when they bore into the bark of trees.
Eggs are laid within a small egg chamber in the cambium of the tree. Each female can produce up to 300 eggs, laid in groups of 50–80, in interconnecting chambers. Eggs are usually laid on one side of the chamber.
Larvae - The beetle has five larval stages (instars), which each become progressively larger. All larval stages feed under the bark in a similar manner: larvae feed side-by-side, packing powdery wood debris (or ‘frass’) and diseased or dead larvae behind them into islands away from the main feeding site. The mixture of resin and frass forms a distinctive quilted pattern.
Pupae are the immobile, resting stage of beetle development before the larvae moult to the adult stage. Pupae are found in pupal cells among the larval frass. They are often found in close proximity and give rise, upon emergence, to aggregations of adults under the bark. These stages can be prolonged over several weeks or months, depending on temperature.
The newly emerged adults are light brown. As they mature the colour darkens to brown and black. Adult beetles move within and between trees mainly by crawling (at temperatures of 12°C or greater), but they occasionally fly (at temperatures of 22.5°C or greater).
Treatment
Information on treating infected trees can be found in the guidance document Minimising the impact of the great spruce bark beetle
Action
Statutory controls against the spread of D. micans were first put in place in Great Britain in 1982. Following the discovery of three new outbreaks outside the main infested area, the Forestry Commission reviewed the controls and consulted the forestry industry on two options: extension of the designation of the infested area and continuing the policy of movement restrictions into Scotland and north-east England, or revocation of our EU protected-zone status. The second of these options was agreed, and from 15 May 2005 the movement within Great Britain of conifer wood and conifer bark was no longer subject to any treatment requirements.
Part of the west of Scotland is designated as a ‘pest-free area’ out of which wood and bark can be moved without treatment under the EU plant passport regime.
0
0
文章
Dummer. ゛☀
2017年09月15日
Asian longhorn beetle (ALB), Anoplophora glabripennis, is a native of China and the Korean peninsula, and poses a serious threat to a wide range of broadleaved trees. It has caused extensive damage to trees in the USA and Italy since being accidentally introduced there in recent years, and there have been outbreaks in several other European Union countries.
The beetles tend to stay close to the site of original infestation in the early stages of an outbreak. However, they can fly more than 2km. Analysis of climate data suggests that most of England and Wales and some warmer coastal areas of Scotland are suitable for beetle establishment, but south-east England and the south coast are at greatest risk.
The lifecycle from egg to beetle is one to two years in parts of Asia, and possibly as long as four years in the UK. Beetles emerge during the summer and will mate and lay eggs, after which they die. Because it is often the resulting emergence holes that are the earliest evidence of an outbreak, it is important to survey and monitor the surrounding area to ensure the adults have not already spread to neighbouring host trees.
Outbreak stage
Individual specimens of Asian longhorn beetle have occasionally been found from time to time in the UK, but in March 2012 a breeding population was confirmed by Forest Research scientists in the Paddock Wood area near Maidstone in Kent.
We and the Food & Environment Research Agency (Fera: now the Animal & Plant Health Agency (APHA)) rapidly implemented measures to eradicate the outbreak and prevent it spreading further afield. More than 4700 potential host trees were surveyed, and 2166 host trees were removed. A total of 66 infested trees were detected, of which only 24 were found by visual inspection, the remaining 42 only being detected after they were felled.
Fortunately this outbreak was detected before the 2012 adult beetle emergence period, which provided time to inspect and deal with infested trees.
Origins
It is suspected that the original beetles might have emerged from wood packaging material which had been used to import slate from China to a site next to where the outbreak was located. Untreated wood packaging is a known pathway for Asian longhorn beetles, and all wood packaging material imported into the EU should be marked to show that it has been treated to reduce the risk of carrying quarantine pests. It is illegal to import wood into the UK which shows signs of the beetle.
Susceptible species
Known hosts (tree species which it can infest) include:
Acer (maples and sycamores)
Aesculus (horse chestnut)
Albizia (Mimosa, silk tree)
Alnus (alder)
Betula (birch)
Carpinus (hornbeam);
Cercidiphyllum japonicum (Katsura tree)
Corylus (hazel)
Fagus (beech)
Fraxinus (ash)
Koelreuteria paniculata; Platanus (plane)
Populus (poplar)
Prunus (cherry, plum)
Robinia pseudoacacia (false acacia/black locust)
Salix (willow, sallow)
Sophora (Pagoda tree)
Sorbus (mountain ash, whitebeam etc)
Quercus palustris (American pin oak)
Quercus rubra (North American red oak)
Ulmus (elm)
Apple and pear trees can also be attacked.
Lifecycle
The lifecycle from egg through larvae to beetle is one to two years in Asia, and possibly longer in the UK. Beetles emerge from spring onwards and will mate and lay eggs, after which they die.
In North America and central and southern parts of Europe, ALB completes its life-cycle in 1-2 years, but in cooler regions the life-cycle can take up to three or four years. It is likely that in southern Britain most individuals will complete their development in two years, and climatic mapping work suggests that conditions along the south coast and south east England would be suitable for a two-year life cycle. Further north, the beetle is less likely to be able to complete its lifecycle in two years. However, there is always an element of uncertainty about these predictions, which results from very local variations in climate, our changing climate, and uncertainties about the origin of the invasive beetles.
Action
Residents and landowners within a 2km buffer zone around the infestation were asked to hold back from any felling/tree surgery or pruning of woody shrubs in gardens. This was because the beetle's larvae live in trunks and branches, so it was important to make sure these were properly disposed of. Residents in this zone who needed to prune or fell trees or woody shrubs were asked to ensure that all woody material was taken to an appropriate Kent County Council waste transfer station or recycling site.
The buffer zone area was extended in 2012 to include an infested tree found on the northernmost edge.
We urged everyone within the 2km buffer zone to keep a look out for, and report, the beetle or evidence of its presence to ensure the best prospects for eradicating this outbreak. We repeated this advice again in summer 2013.
We have re-surveyed the area every year to check for signs of any contnuing presence of the pest. No further evidence of its presence has been found, but will continue the surveys until 2018 before we can declare the pest eradicated from the area.
The only insecticides that could be considered are not completely effective, so there is no real substitute for tree removal as a means of eradicating Asian longhorn beetle.
ALB does not attack wood in houses. The adults only lay their eggs on living trees, and although the larvae can continue to develop in felled wood, the early-stage larvae require the conditions and nutrition found in living wood.
Movement controls and treatment
This pest is regulated, so movement of plants, logs and wood from infested areas is subject to statutory controls. Movement restrictions on host plants and woody material for two commercial retailers in the affected areas were implemented by plant health notices.
We advised local people not to undertake any tree surgery or felling until we had completed our survey, unless it was necessary for safety reasons, or to move any logs or branches which had been recently felled. Movement of infested material could carry the beetle to new locations. Also, the larvae can complete their development in felled trees or branches if left untreated, especially in the summer months, so this material would present an ongoing hazard.
Notices were served on plant retailers in the affected area to prevent the movement of any potentially infested host plants or host plant material (with stems more than 2cm in diameter).
Larvae within wood will not survive if the wood is chipped to lengths no longer than 25mm. Once the wood has been chipped in this way it is deemed safe and can be disposed of.
There is no reason to restrict people’s movements in infested areas or buffer zones. The only possible restrictions would have been brief local exclusions for safety reasons during any tree felling which became necessary.
Identification
Some common native beetles can be mistaken for Asian longhorn beetles. The adult beetles are large, about 20-40 mm long, and shiny black with variable white markings. Particularly distinctive are their antennae, which are up to twice the body length and black with white or light blue bands. They are almost identical in appearance to citrus longhorn beetle (Anoplophora chinensis), another non-indigenous longhorn beetle that threatens trees in Britain.
The most obvious symptoms of Asian longhorn beetle damage are the circular exit holes made by the emerging adult beetles in the trunks and branches, which are about 10 mm in diameter and are usually found in the main trunk and above.
Other signs which might be present, but less obvious, include piles of sawdust-like droppings at the base of infested trees, scraped bark, possibly sap bleeding from sites where eggs have been laid, and feeding damage on the bark of smaller branches and shoots.
The beetles tend to stay close to the site of original infestation in the early stages of an outbreak. However, they can fly more than 2km. Analysis of climate data suggests that most of England and Wales and some warmer coastal areas of Scotland are suitable for beetle establishment, but south-east England and the south coast are at greatest risk.
The lifecycle from egg to beetle is one to two years in parts of Asia, and possibly as long as four years in the UK. Beetles emerge during the summer and will mate and lay eggs, after which they die. Because it is often the resulting emergence holes that are the earliest evidence of an outbreak, it is important to survey and monitor the surrounding area to ensure the adults have not already spread to neighbouring host trees.
Outbreak stage
Individual specimens of Asian longhorn beetle have occasionally been found from time to time in the UK, but in March 2012 a breeding population was confirmed by Forest Research scientists in the Paddock Wood area near Maidstone in Kent.
We and the Food & Environment Research Agency (Fera: now the Animal & Plant Health Agency (APHA)) rapidly implemented measures to eradicate the outbreak and prevent it spreading further afield. More than 4700 potential host trees were surveyed, and 2166 host trees were removed. A total of 66 infested trees were detected, of which only 24 were found by visual inspection, the remaining 42 only being detected after they were felled.
Fortunately this outbreak was detected before the 2012 adult beetle emergence period, which provided time to inspect and deal with infested trees.
Origins
It is suspected that the original beetles might have emerged from wood packaging material which had been used to import slate from China to a site next to where the outbreak was located. Untreated wood packaging is a known pathway for Asian longhorn beetles, and all wood packaging material imported into the EU should be marked to show that it has been treated to reduce the risk of carrying quarantine pests. It is illegal to import wood into the UK which shows signs of the beetle.
Susceptible species
Known hosts (tree species which it can infest) include:
Acer (maples and sycamores)
Aesculus (horse chestnut)
Albizia (Mimosa, silk tree)
Alnus (alder)
Betula (birch)
Carpinus (hornbeam);
Cercidiphyllum japonicum (Katsura tree)
Corylus (hazel)
Fagus (beech)
Fraxinus (ash)
Koelreuteria paniculata; Platanus (plane)
Populus (poplar)
Prunus (cherry, plum)
Robinia pseudoacacia (false acacia/black locust)
Salix (willow, sallow)
Sophora (Pagoda tree)
Sorbus (mountain ash, whitebeam etc)
Quercus palustris (American pin oak)
Quercus rubra (North American red oak)
Ulmus (elm)
Apple and pear trees can also be attacked.
Lifecycle
The lifecycle from egg through larvae to beetle is one to two years in Asia, and possibly longer in the UK. Beetles emerge from spring onwards and will mate and lay eggs, after which they die.
In North America and central and southern parts of Europe, ALB completes its life-cycle in 1-2 years, but in cooler regions the life-cycle can take up to three or four years. It is likely that in southern Britain most individuals will complete their development in two years, and climatic mapping work suggests that conditions along the south coast and south east England would be suitable for a two-year life cycle. Further north, the beetle is less likely to be able to complete its lifecycle in two years. However, there is always an element of uncertainty about these predictions, which results from very local variations in climate, our changing climate, and uncertainties about the origin of the invasive beetles.
Action
Residents and landowners within a 2km buffer zone around the infestation were asked to hold back from any felling/tree surgery or pruning of woody shrubs in gardens. This was because the beetle's larvae live in trunks and branches, so it was important to make sure these were properly disposed of. Residents in this zone who needed to prune or fell trees or woody shrubs were asked to ensure that all woody material was taken to an appropriate Kent County Council waste transfer station or recycling site.
The buffer zone area was extended in 2012 to include an infested tree found on the northernmost edge.
We urged everyone within the 2km buffer zone to keep a look out for, and report, the beetle or evidence of its presence to ensure the best prospects for eradicating this outbreak. We repeated this advice again in summer 2013.
We have re-surveyed the area every year to check for signs of any contnuing presence of the pest. No further evidence of its presence has been found, but will continue the surveys until 2018 before we can declare the pest eradicated from the area.
The only insecticides that could be considered are not completely effective, so there is no real substitute for tree removal as a means of eradicating Asian longhorn beetle.
ALB does not attack wood in houses. The adults only lay their eggs on living trees, and although the larvae can continue to develop in felled wood, the early-stage larvae require the conditions and nutrition found in living wood.
Movement controls and treatment
This pest is regulated, so movement of plants, logs and wood from infested areas is subject to statutory controls. Movement restrictions on host plants and woody material for two commercial retailers in the affected areas were implemented by plant health notices.
We advised local people not to undertake any tree surgery or felling until we had completed our survey, unless it was necessary for safety reasons, or to move any logs or branches which had been recently felled. Movement of infested material could carry the beetle to new locations. Also, the larvae can complete their development in felled trees or branches if left untreated, especially in the summer months, so this material would present an ongoing hazard.
Notices were served on plant retailers in the affected area to prevent the movement of any potentially infested host plants or host plant material (with stems more than 2cm in diameter).
Larvae within wood will not survive if the wood is chipped to lengths no longer than 25mm. Once the wood has been chipped in this way it is deemed safe and can be disposed of.
There is no reason to restrict people’s movements in infested areas or buffer zones. The only possible restrictions would have been brief local exclusions for safety reasons during any tree felling which became necessary.
Identification
Some common native beetles can be mistaken for Asian longhorn beetles. The adult beetles are large, about 20-40 mm long, and shiny black with variable white markings. Particularly distinctive are their antennae, which are up to twice the body length and black with white or light blue bands. They are almost identical in appearance to citrus longhorn beetle (Anoplophora chinensis), another non-indigenous longhorn beetle that threatens trees in Britain.
The most obvious symptoms of Asian longhorn beetle damage are the circular exit holes made by the emerging adult beetles in the trunks and branches, which are about 10 mm in diameter and are usually found in the main trunk and above.
Other signs which might be present, but less obvious, include piles of sawdust-like droppings at the base of infested trees, scraped bark, possibly sap bleeding from sites where eggs have been laid, and feeding damage on the bark of smaller branches and shoots.
0
0
文章
Dummer. ゛☀
2017年09月15日
Distorted and misshapen leaves, flowers, buds and fruit growth. The leaf tissue around affected areas may become brown and eventually die.
Plants affected
Many different garden plants are affected including fruits, vegetables, ornamentals, trees and weeds.
About Capsid bugs
Capsid bugs feed on plant sap and in doing so cause deformation of plant material.
There are many different species of capsid bugs in the UK.
Capsids are also known as mirid bugs.
Some species of capsid also feed on other small insects.
Adults vary in colour from green to red/ brown, around 6mm in length, and have a long, slender feeding tube.
Young are similar in shape and colour, but smaller and wingless.
When disturbed they fall down onto the soil as a defence.
When feeding they inject saliva which is toxic to plants.
There can be one or two generations per year depending on the species.
Eggs are laid into cracks in tree bark, woody stems, and at the base of hedges. They hatch in late spring.
Depending on species, over-wintering takes place as eggs or as adults in plant debris.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Capsid bugs
Pyrethrins
Pyrethroids
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Regularly inspect plants in spring.
Remove and destroy adults by hand.
Winter wash trees to destroy eggs.
Prevention
Keep areas around plants free from plant debris.
Remove weeds around plants.
Plants affected
Many different garden plants are affected including fruits, vegetables, ornamentals, trees and weeds.
About Capsid bugs
Capsid bugs feed on plant sap and in doing so cause deformation of plant material.
There are many different species of capsid bugs in the UK.
Capsids are also known as mirid bugs.
Some species of capsid also feed on other small insects.
Adults vary in colour from green to red/ brown, around 6mm in length, and have a long, slender feeding tube.
Young are similar in shape and colour, but smaller and wingless.
When disturbed they fall down onto the soil as a defence.
When feeding they inject saliva which is toxic to plants.
There can be one or two generations per year depending on the species.
Eggs are laid into cracks in tree bark, woody stems, and at the base of hedges. They hatch in late spring.
Depending on species, over-wintering takes place as eggs or as adults in plant debris.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Capsid bugs
Pyrethrins
Pyrethroids
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Regularly inspect plants in spring.
Remove and destroy adults by hand.
Winter wash trees to destroy eggs.
Prevention
Keep areas around plants free from plant debris.
Remove weeds around plants.
0
0
文章
Dummer. ゛☀
2017年09月15日
Sawflies (Caliroa cerasi), also known as cherry or pear slugs, are widely distributed throughout the United States and Canada. They are a common pest of mountain ash, hawthorn, cotoneaster, cherry, plum and pear trees, and are occasionally found on quince and shadbush. High populations can defoliate entire trees.
Young larvae (1/2 inch long) are greenish-black, elongated, slim and slug-like, with very little evidence of legs. As the slugs grow, they become lighter colored. When fully mature, pear sawfly larvae resemble green-orange caterpillars. The adult (1/5 inch long) is a black and yellow, 4-winged non-stinging wasp (sawfly) that is rarely noticed.
Life Cycle
The winter is passed in the soil inside a cocoon. In the late spring, shortly after trees have come into full leaf, the adults emerge and deposit their eggs in the leaves. These hatch a week or more later, depending on temperature. Larval development is completed in less than a month and pupation takes place in the soil. Adults emerge during late July and August and lay eggs for the second generation of slugs. This generation usually causes the greatest amount of injury, especially on young trees which they may completely defoliate. When this second generation of larvae becomes fully grown, they go into the ground and remain as larvae until the following spring, when they pupate. There is usually only one generation per year, but there may be a partial second.
Sawfly Control
Cultivate around trees and shrubs in the early spring and again in the fall to help reduce the overwintering population.
Wash slugs off leaves with a strong jet of water from the Bug Blaster; larvae may also be sprayed with Safer® Soap.
Apply food-grade Diatomaceous Earth for long-lasting protection. Made up of tiny fossilized aquatic organisms, that look like broken glass under the microscope, DE kills by scoring an insect’s outer layer as it crawls over the fine powder. Contains NO toxic poisons!
Azatrol EC contains azadirachtin, the key insecticidal ingredient found in neem oil. This concentrated, organic insecticide offers multiple modes of action, making it virtually impossible for insect resistance to develop. Best of all, it’s non-toxic to honey bees and many other beneficial insects.
Surround WP (kaolin clay) forms a protective barrier film, which acts as a broad spectrum crop protectant for preventing damage from insect pests.
Many growers are reporting great success with Monterey® Garden Insect Spray (Spinosad). A relatively new insect killer, it can be applied to a large number of ornamental and garden plants. Best of all, it’s OMRI Listed for use in organic production.
Least-toxic botanical insecticides should be used as a last resort. Derived from plants which have insecticidal properties, these natural pesticides have fewer harmful side effects than synthetic chemicals and break down more quickly in the environment.
Young larvae (1/2 inch long) are greenish-black, elongated, slim and slug-like, with very little evidence of legs. As the slugs grow, they become lighter colored. When fully mature, pear sawfly larvae resemble green-orange caterpillars. The adult (1/5 inch long) is a black and yellow, 4-winged non-stinging wasp (sawfly) that is rarely noticed.
Life Cycle
The winter is passed in the soil inside a cocoon. In the late spring, shortly after trees have come into full leaf, the adults emerge and deposit their eggs in the leaves. These hatch a week or more later, depending on temperature. Larval development is completed in less than a month and pupation takes place in the soil. Adults emerge during late July and August and lay eggs for the second generation of slugs. This generation usually causes the greatest amount of injury, especially on young trees which they may completely defoliate. When this second generation of larvae becomes fully grown, they go into the ground and remain as larvae until the following spring, when they pupate. There is usually only one generation per year, but there may be a partial second.
Sawfly Control
Cultivate around trees and shrubs in the early spring and again in the fall to help reduce the overwintering population.
Wash slugs off leaves with a strong jet of water from the Bug Blaster; larvae may also be sprayed with Safer® Soap.
Apply food-grade Diatomaceous Earth for long-lasting protection. Made up of tiny fossilized aquatic organisms, that look like broken glass under the microscope, DE kills by scoring an insect’s outer layer as it crawls over the fine powder. Contains NO toxic poisons!
Azatrol EC contains azadirachtin, the key insecticidal ingredient found in neem oil. This concentrated, organic insecticide offers multiple modes of action, making it virtually impossible for insect resistance to develop. Best of all, it’s non-toxic to honey bees and many other beneficial insects.
Surround WP (kaolin clay) forms a protective barrier film, which acts as a broad spectrum crop protectant for preventing damage from insect pests.
Many growers are reporting great success with Monterey® Garden Insect Spray (Spinosad). A relatively new insect killer, it can be applied to a large number of ornamental and garden plants. Best of all, it’s OMRI Listed for use in organic production.
Least-toxic botanical insecticides should be used as a last resort. Derived from plants which have insecticidal properties, these natural pesticides have fewer harmful side effects than synthetic chemicals and break down more quickly in the environment.
0
0
文章
Dummer. ゛☀
2017年09月15日
A serious late season pest of pecan and hickory trees, the pecan weevil (Curculio caryae) chews holes through the shuck and shell of nuts and are responsible for two kinds of damage.
The first type of damage is caused by adult weevils feeding on kernels prior to the shells hardening. Nuts punctured by weevils during this stage have a tobacco-juice-like stain around the feeding site. Damaged nuts often shrivel, turn black inside and drop prematurely.
The second type of damage occurs later in the growing season when females place eggs within the newly formed kernels. Larvae hatch and feed within the kernel causing further damage. These infested nuts do not drop and are often harvested along with a healthy crop. The pecan weevil causes serious economic loses wherever pecan and hickory trees are grown.
Adults are hard shelled beetles about 3/8 inch long with long slender snouts (females have a snout longer than their bodies) and thin legs. They are reddish brown in color and densely covered with olive-brown hairs and scales. Larvae are fat, creamy white, C-shaped grubs. They have reddish-brown heads and grow to 1/3 inch long.
Life Cycle
Adult weevils and larvae overwinter in the soil. The majority of adults emerge from the soil during August and the first week of September. When nuts reach the dough stage of development, mated females lay 2-4 eggs in separate pockets within the kernels. After eggs hatch, young legless larvae feed for about 30-35 days inside pecans. Between late September and December larvae exit nuts through a small circular hole, drop to the ground and burrow into the soil to a depth of 4-12 inches. They spend one to two years in the soil before pupating in the fall. (Most of the grubs will pupate the following fall. Although some do not pupate until the fall of the next year.) The pupal stage lasts about three weeks. Adults remain in the soil until the following summer. There is one generation every 2-3 years.
Control
Spread in bands around the base of trees, Tanglefoot® Pest Barrier will prevent adult weevils from reaching the nuts on which they feed.
Beneficial nematodes are microscopic, worm-like parasites that actively hunt, penetrate and destroy pecan weevil larvae in the soil. Applications should be made around the base of trees, out to the drip line — or a little farther.
Azatrol EC contains azadirachtin, the key insecticidal ingredient found in neem oil. This broad spectrum, organic spray disrupts growth and development of pest insects and has repellent and anti-feedant properties. Best of all, it’s non-toxic to honey bees and many other beneficial insects.
Growers with only a few trees can place tarps under the canopy during August, especially several days after a rain, and jar the limbs to shake adults free. Weevils that fall will remain still for several minutes and can be collected and destroyed in a bucket of soapy water. This technique can be repeated until mid-September or until no weevils are found.
Apply fast-acting botanical insecticides after 6 weevils are jarred from a single tree. Normally, three to five sprays every 5-7 days are required. These natural pesticides will also prevent egg laying by adults, if applied soon after adults emerge.
The first type of damage is caused by adult weevils feeding on kernels prior to the shells hardening. Nuts punctured by weevils during this stage have a tobacco-juice-like stain around the feeding site. Damaged nuts often shrivel, turn black inside and drop prematurely.
The second type of damage occurs later in the growing season when females place eggs within the newly formed kernels. Larvae hatch and feed within the kernel causing further damage. These infested nuts do not drop and are often harvested along with a healthy crop. The pecan weevil causes serious economic loses wherever pecan and hickory trees are grown.
Adults are hard shelled beetles about 3/8 inch long with long slender snouts (females have a snout longer than their bodies) and thin legs. They are reddish brown in color and densely covered with olive-brown hairs and scales. Larvae are fat, creamy white, C-shaped grubs. They have reddish-brown heads and grow to 1/3 inch long.
Life Cycle
Adult weevils and larvae overwinter in the soil. The majority of adults emerge from the soil during August and the first week of September. When nuts reach the dough stage of development, mated females lay 2-4 eggs in separate pockets within the kernels. After eggs hatch, young legless larvae feed for about 30-35 days inside pecans. Between late September and December larvae exit nuts through a small circular hole, drop to the ground and burrow into the soil to a depth of 4-12 inches. They spend one to two years in the soil before pupating in the fall. (Most of the grubs will pupate the following fall. Although some do not pupate until the fall of the next year.) The pupal stage lasts about three weeks. Adults remain in the soil until the following summer. There is one generation every 2-3 years.
Control
Spread in bands around the base of trees, Tanglefoot® Pest Barrier will prevent adult weevils from reaching the nuts on which they feed.
Beneficial nematodes are microscopic, worm-like parasites that actively hunt, penetrate and destroy pecan weevil larvae in the soil. Applications should be made around the base of trees, out to the drip line — or a little farther.
Azatrol EC contains azadirachtin, the key insecticidal ingredient found in neem oil. This broad spectrum, organic spray disrupts growth and development of pest insects and has repellent and anti-feedant properties. Best of all, it’s non-toxic to honey bees and many other beneficial insects.
Growers with only a few trees can place tarps under the canopy during August, especially several days after a rain, and jar the limbs to shake adults free. Weevils that fall will remain still for several minutes and can be collected and destroyed in a bucket of soapy water. This technique can be repeated until mid-September or until no weevils are found.
Apply fast-acting botanical insecticides after 6 weevils are jarred from a single tree. Normally, three to five sprays every 5-7 days are required. These natural pesticides will also prevent egg laying by adults, if applied soon after adults emerge.
0
0
文章
Dummer. ゛☀
2017年09月15日
The peach tree borer (Synanthedon exitiosa) does damage to a variety of stone fruit trees. It attacks not the fruit, but the tree itself, burrowing into its trunk near or beneath ground level and devouring its way into the living cambium layer underneath.
Heavy infestations, recognizable from the circle of oozing frass (the larvae’s excreted waste) around the trunk, can completely girdle trees, killing them if left untreated. Young trees are especially vulnerable. Older trees that survive attacks will show less vigor and inferior fruit quality.
Borers are historically found across the United States and in parts of Canada, almost anywhere stone fruits grow. They existed on wild cherry and plum trees before non-native apricots, nectarines and peaches were introduced. Today, they’re a common and persistent threat to both commercial and home orchardists.
The larvae of peachtree borers are white to beige and brown and obtain an length of an inch or more. The chewing end of the larvae darkens as it matures. Despite they’re size, they’re seldom seen as they bore beneath a tree’s bark, gouging out wide, fass-filled tunnels. Pupae, wrapped in silky cocoons, are also unseen hidden inside the tree.
Adult moths have translucent wings and resemble wasps. Females are metallic blue and marked with an orange band on their abdomen. Males are smaller and are marked with yellow stripes. Their emergence a week or two into the summer sets off a frenzy of mating and egg laying.
The lesser peachtree borer (Synanthedon pictipes) is found in the eastern United States, across the southern states to Texas and the midwestern states to Minnesota. It attacks more of the tree, including primary limbs, and is more likely than Synanthedon exitiosa to produce eggs throughout the season. Larva are similar in appearance to exitiosa, but male moths have narrower, more numerous yellow bands across their abdomens. The pest’s life cycle and treatment is similar to those of exitiosa.
Life Cycle
Adults begin emerging in late spring and early summer from larvae that have overwintered inside the tree an inch or two beneath the soil line. They continue to emerge throughout the summer and into the fall. Knowing when moths first emerge in your region, as early as April in Georgia and other warmer areas but more commonly in May and June, is critical to controlling the pest.
The moths begin breeding almost as soon as they emerge. Females lay as many as 400 eggs on the trunk of the tree near the soil line or in the soil against the tree. The eggs take ten days to hatch.
Larvae immediately seek entrance into the tree’s bark, often through cracks, chips and other damage. They tunnel through the bark into the vulnerable cambium layer beneath it and beyond, growing as they do. Some may pass through to adult stage in a single season. As cold weather sets in, larvae will reduce activity and overwinter inside the tree. They begin feeding again when temperatures warm.
In spring, the larvae migrate from their holes, pupating near the entrance to their burrow or in nearby soil, creating a gummy cocoon of silk thread and bits of wood. The cocooning and pupation stages before moths emerge takes as much as four weeks. Moths begin laying eggs within minutes of taking to the air.
Utah State University Extension Cooperative (PDF) has wonderful color photographs of the pest’s various stages.
Damage
Peach tree borers bring major harm to important fruit-crop trees, destroying the tree’s vascular system through boring and girdling while inducing plant pathogens to invade the weakened tree.
Colorado State University’s Extension website doesn’t pull punches when addressing the pest’s effect on home and commercial growers, calling it “the most destructive insect pest of peach, cherry, plum and other stone fruits in Colorado.” The University of Florida’s Institute of Food and Agricultural Sciences provides perspective: “The peachtree borer and the lesser peachtree borer, Synanthedon pictipes, account for more damage to peach trees than all other insect pest combined.”
Borer damage inhibits the conduction of water and nutrients up the trunk to the tree’s branches, leaves and fruits. One or two borers will harm its growth and fruiting. Several burrowing into the same tree, fouling their tunnels with their waste, can kill a newly infested tree in a single season.
Infestation are most common in older trees that have seen damage from canker, harsh winters, pruning and mechanical injury (like trunks being hit by mowers). This give the larvae an easy way into the tree’s insides. The lesser peachtree borer is particularly attracted to older, damaged trees. Numerous larvae cluster at these places in “galleries” where substantial damage may be done.
The Missouri Botanical Garden has photos of damage signs as well as the larvae at work.
Control
Don’t allow borers to get established. Most trees will survive attack from small numbers. But large numbers of larvae can completely girdle a tree, killing it. Once the larvae move into the bark, they are difficult to manage. They’re most vulnerable at the surface before they chew their way into the tree’s bark and cambium layer.
Wild trees provide a year-to-year home for borers. If you have wild plum, cherry or other stone fruits in your woodlot, consider clearing them. Female adults are attracted to diseased, damaged and otherwise stressed trees. Removing and replacing older, stressed trees that harbor borers can help make control issues easier to deposit their eggs.
Healthy, adequately watered trees are less likely to invite infestation. Take care to keep your trees strong and undamaged.
Borer treatment begins early in spring even before larvae become active. Probe small holes in trunks near the soil line, especially those with evidence of frass, with the point of a knife or stiff wire to crush larvae (and later pupae) beneath the bark. In severe infestations, scoop soil out from around the crown of the tree where frass collects and use a sharp-pointed object to dig out the larvae, taking care not to harm the tree.
Be on watch and prepared for the emergence of adult moths. Because they begin breeding and laying eggs within hours of emerging, it’s important to treat for them as soon as they appear. Ask local nurserymen when the first moths are expected in your area. Monitor trees for moth activity daily and keep journal records for future years. Use pheromone traps or Tangle-Trap® Insect Trap Coating to capture adults. Inspect traps daily.
Begin spraying organic neem oil in the highest recommended concentrations around the crown of the tree and up the first six to 12 inches of the trunk when adults are anticipated. Saturate both bark and soil. The oil will disrupt the moths’ breeding cycle and discourage them from leaving eggs. It will also neutralize eggs that may already have been laid as well as penetrate the bark and inhibit development of larvae already in the tree. Spray twice a month throughout the breeding season which can last until September. Reapply after rains.
Citrus extract sprays will repel adults and discourage egg laying. Begin spraying trunks and around the crown of the tree just ahead of moth hatch.
Paint tree trunks and exposed roots with a paste of Surround WP, a powder made of kaolin clay. Coat base of tree, exposed roots and trunk up to 12 inches. Once dry, the coating deters adults and their egg laying.
Applications of Bt (Bacillus thuringiensis), a naturally occurring soil bacteria, will disrupt larvae and kill them depending on exposure. Spray Bt directly into borer holes after clearing out as much frass as possible.
Spinosad, an OMRI listed pesticide, can also be sprayed on tree trunks as larvae hatch and directly into borer holes. Spraying can be repeated every five or six days up to two weeks before harvest.
A recent study has shown that beneficial nematodes work against this destructive scourge. Nematodes attack eggs, larvae and pupae of numerous insect pests in soil. A spring application of nematodes suppressed 88% of orchard borer infestations. Spring and fall applications were found to be 100% effective.
Parasitic wasps can help with lesser peach tree borer whose eggs can be found. They are not effective on the pupae of the common, greater peachtree borer because they’re under the soil line out of the wasp’s reach. But certain wasps will parasitize eggs found on bark and just-hatched larvae that have not yet worked their way into the tree.
Woodpeckers and other birds will reduce numbers by grabbing larvae on and under the bark. Encourage them by providing suitable habitat and not spraying harmful pesticides.
Cedar chips and bark spread around the base of stone fruit trees is said to repel egg-laying adult moths. In the south, spreading tobacco dust around the base of trees is a traditional method of discouraging pests.
Some do-it-yourself sources advise the use of moth crystals to “gas” the larvae inside their burrows. It’s suggested that crystals worked into the soil at the trees crown will emit vapor that penetrates into the tree. Moth crystals, like moth balls, are made from napthalene, a suspected carcinogen which is also linked to liver failure and neurological damage in infants. Using and handling naphthalene — not a natural-gardening practice — should be avoided.
Heavy infestations, recognizable from the circle of oozing frass (the larvae’s excreted waste) around the trunk, can completely girdle trees, killing them if left untreated. Young trees are especially vulnerable. Older trees that survive attacks will show less vigor and inferior fruit quality.
Borers are historically found across the United States and in parts of Canada, almost anywhere stone fruits grow. They existed on wild cherry and plum trees before non-native apricots, nectarines and peaches were introduced. Today, they’re a common and persistent threat to both commercial and home orchardists.
The larvae of peachtree borers are white to beige and brown and obtain an length of an inch or more. The chewing end of the larvae darkens as it matures. Despite they’re size, they’re seldom seen as they bore beneath a tree’s bark, gouging out wide, fass-filled tunnels. Pupae, wrapped in silky cocoons, are also unseen hidden inside the tree.
Adult moths have translucent wings and resemble wasps. Females are metallic blue and marked with an orange band on their abdomen. Males are smaller and are marked with yellow stripes. Their emergence a week or two into the summer sets off a frenzy of mating and egg laying.
The lesser peachtree borer (Synanthedon pictipes) is found in the eastern United States, across the southern states to Texas and the midwestern states to Minnesota. It attacks more of the tree, including primary limbs, and is more likely than Synanthedon exitiosa to produce eggs throughout the season. Larva are similar in appearance to exitiosa, but male moths have narrower, more numerous yellow bands across their abdomens. The pest’s life cycle and treatment is similar to those of exitiosa.
Life Cycle
Adults begin emerging in late spring and early summer from larvae that have overwintered inside the tree an inch or two beneath the soil line. They continue to emerge throughout the summer and into the fall. Knowing when moths first emerge in your region, as early as April in Georgia and other warmer areas but more commonly in May and June, is critical to controlling the pest.
The moths begin breeding almost as soon as they emerge. Females lay as many as 400 eggs on the trunk of the tree near the soil line or in the soil against the tree. The eggs take ten days to hatch.
Larvae immediately seek entrance into the tree’s bark, often through cracks, chips and other damage. They tunnel through the bark into the vulnerable cambium layer beneath it and beyond, growing as they do. Some may pass through to adult stage in a single season. As cold weather sets in, larvae will reduce activity and overwinter inside the tree. They begin feeding again when temperatures warm.
In spring, the larvae migrate from their holes, pupating near the entrance to their burrow or in nearby soil, creating a gummy cocoon of silk thread and bits of wood. The cocooning and pupation stages before moths emerge takes as much as four weeks. Moths begin laying eggs within minutes of taking to the air.
Utah State University Extension Cooperative (PDF) has wonderful color photographs of the pest’s various stages.
Damage
Peach tree borers bring major harm to important fruit-crop trees, destroying the tree’s vascular system through boring and girdling while inducing plant pathogens to invade the weakened tree.
Colorado State University’s Extension website doesn’t pull punches when addressing the pest’s effect on home and commercial growers, calling it “the most destructive insect pest of peach, cherry, plum and other stone fruits in Colorado.” The University of Florida’s Institute of Food and Agricultural Sciences provides perspective: “The peachtree borer and the lesser peachtree borer, Synanthedon pictipes, account for more damage to peach trees than all other insect pest combined.”
Borer damage inhibits the conduction of water and nutrients up the trunk to the tree’s branches, leaves and fruits. One or two borers will harm its growth and fruiting. Several burrowing into the same tree, fouling their tunnels with their waste, can kill a newly infested tree in a single season.
Infestation are most common in older trees that have seen damage from canker, harsh winters, pruning and mechanical injury (like trunks being hit by mowers). This give the larvae an easy way into the tree’s insides. The lesser peachtree borer is particularly attracted to older, damaged trees. Numerous larvae cluster at these places in “galleries” where substantial damage may be done.
The Missouri Botanical Garden has photos of damage signs as well as the larvae at work.
Control
Don’t allow borers to get established. Most trees will survive attack from small numbers. But large numbers of larvae can completely girdle a tree, killing it. Once the larvae move into the bark, they are difficult to manage. They’re most vulnerable at the surface before they chew their way into the tree’s bark and cambium layer.
Wild trees provide a year-to-year home for borers. If you have wild plum, cherry or other stone fruits in your woodlot, consider clearing them. Female adults are attracted to diseased, damaged and otherwise stressed trees. Removing and replacing older, stressed trees that harbor borers can help make control issues easier to deposit their eggs.
Healthy, adequately watered trees are less likely to invite infestation. Take care to keep your trees strong and undamaged.
Borer treatment begins early in spring even before larvae become active. Probe small holes in trunks near the soil line, especially those with evidence of frass, with the point of a knife or stiff wire to crush larvae (and later pupae) beneath the bark. In severe infestations, scoop soil out from around the crown of the tree where frass collects and use a sharp-pointed object to dig out the larvae, taking care not to harm the tree.
Be on watch and prepared for the emergence of adult moths. Because they begin breeding and laying eggs within hours of emerging, it’s important to treat for them as soon as they appear. Ask local nurserymen when the first moths are expected in your area. Monitor trees for moth activity daily and keep journal records for future years. Use pheromone traps or Tangle-Trap® Insect Trap Coating to capture adults. Inspect traps daily.
Begin spraying organic neem oil in the highest recommended concentrations around the crown of the tree and up the first six to 12 inches of the trunk when adults are anticipated. Saturate both bark and soil. The oil will disrupt the moths’ breeding cycle and discourage them from leaving eggs. It will also neutralize eggs that may already have been laid as well as penetrate the bark and inhibit development of larvae already in the tree. Spray twice a month throughout the breeding season which can last until September. Reapply after rains.
Citrus extract sprays will repel adults and discourage egg laying. Begin spraying trunks and around the crown of the tree just ahead of moth hatch.
Paint tree trunks and exposed roots with a paste of Surround WP, a powder made of kaolin clay. Coat base of tree, exposed roots and trunk up to 12 inches. Once dry, the coating deters adults and their egg laying.
Applications of Bt (Bacillus thuringiensis), a naturally occurring soil bacteria, will disrupt larvae and kill them depending on exposure. Spray Bt directly into borer holes after clearing out as much frass as possible.
Spinosad, an OMRI listed pesticide, can also be sprayed on tree trunks as larvae hatch and directly into borer holes. Spraying can be repeated every five or six days up to two weeks before harvest.
A recent study has shown that beneficial nematodes work against this destructive scourge. Nematodes attack eggs, larvae and pupae of numerous insect pests in soil. A spring application of nematodes suppressed 88% of orchard borer infestations. Spring and fall applications were found to be 100% effective.
Parasitic wasps can help with lesser peach tree borer whose eggs can be found. They are not effective on the pupae of the common, greater peachtree borer because they’re under the soil line out of the wasp’s reach. But certain wasps will parasitize eggs found on bark and just-hatched larvae that have not yet worked their way into the tree.
Woodpeckers and other birds will reduce numbers by grabbing larvae on and under the bark. Encourage them by providing suitable habitat and not spraying harmful pesticides.
Cedar chips and bark spread around the base of stone fruit trees is said to repel egg-laying adult moths. In the south, spreading tobacco dust around the base of trees is a traditional method of discouraging pests.
Some do-it-yourself sources advise the use of moth crystals to “gas” the larvae inside their burrows. It’s suggested that crystals worked into the soil at the trees crown will emit vapor that penetrates into the tree. Moth crystals, like moth balls, are made from napthalene, a suspected carcinogen which is also linked to liver failure and neurological damage in infants. Using and handling naphthalene — not a natural-gardening practice — should be avoided.
0
0
文章
Dummer. ゛☀
2017年09月15日
Common on backyard trees, ornamental shrubs, greenhouse plants and houseplants, over 1,000 species of scale insects exist in North America. They are such oddly shaped and immobile pests that they often resemble shell-like bumps rather than insects. In many cases, heavy infestations build up unnoticed before plants begin to show damage. Large populations may result in poor growth, reduced vigor and chlorotic (yellowed) leaves. If left unchecked, an infested host may become so weak that it dies.
Scale insects can be divided into two groups:
Armored (Hard) – Secrete a hard protective covering (1/8 inch long) over themselves, which is not attached to the body. The hard scale lives and feeds under this spherical armor and does not move about the plant. They do not secrete honeydew.
Soft – Secrete a waxy film (up to 1/2 inch long) that is part of the body. In most cases, they are able to move short distances (but rarely do) and produce copious amounts of honeydew. Soft scale vary in shape from flat to almost spherical.
Life Cycle
Adult females lay eggs underneath their protective covering which hatch over a period of one to three weeks. The newly hatched nymphs (called crawlers) migrate out from this covering and move about the plant until a suitable feeding site is found. Young nymphs insert their piercing mouthparts into the plant and begin to feed, gradually developing their own armor as they transform into immobile adults. They do not pupate and may have several overlapping generations per year, especially in greenhouses.
Note: Males of many species develop wings as adults and appear as tiny gnat-like insects. They are rarely seen and do not feed on plants. Females often reproduce without mating.
Control
To get rid of scale insects prune and dispose of infested branches, twigs and leaves.
When scale numbers are low they may be rubbed or picked off of plants by hand.
Dabbing individual pests with an alcohol-soaked cotton swab or neem-based leaf shine will also work when infestations are light.
Commercially available beneficial insects, such as ladybugs and lacewing, are natural predators of the young larval or “crawler” stage.
Organic pesticides, like insecticidal soap and d-Limonene can also be used to kill the larvae. However, these products have very little persistence in the environment, so several applications during egg-hatching will be required for effective control.
Azamax contains azadirachtin, the key insecticidal ingredient found in neem oil. This concentrated spray is approved for organic use and offers multiple modes of action, making it virtually impossible for pest resistance to develop. Best of all, it’s non-toxic to honey bees and many other beneficial insects.
Horticultural oils and other safe, oil-based insecticides work by smothering insects and will control all pest stages, including adults which are protected from most other insecticides by their armor coverings.
Fast-acting botanical insecticides should be used as a last resort. Derived from plants which have insecticidal properties, these natural pesticides have fewer harmful side effects than synthetic chemicals and break down more quickly in the environment.
Scale insects can be divided into two groups:
Armored (Hard) – Secrete a hard protective covering (1/8 inch long) over themselves, which is not attached to the body. The hard scale lives and feeds under this spherical armor and does not move about the plant. They do not secrete honeydew.
Soft – Secrete a waxy film (up to 1/2 inch long) that is part of the body. In most cases, they are able to move short distances (but rarely do) and produce copious amounts of honeydew. Soft scale vary in shape from flat to almost spherical.
Life Cycle
Adult females lay eggs underneath their protective covering which hatch over a period of one to three weeks. The newly hatched nymphs (called crawlers) migrate out from this covering and move about the plant until a suitable feeding site is found. Young nymphs insert their piercing mouthparts into the plant and begin to feed, gradually developing their own armor as they transform into immobile adults. They do not pupate and may have several overlapping generations per year, especially in greenhouses.
Note: Males of many species develop wings as adults and appear as tiny gnat-like insects. They are rarely seen and do not feed on plants. Females often reproduce without mating.
Control
To get rid of scale insects prune and dispose of infested branches, twigs and leaves.
When scale numbers are low they may be rubbed or picked off of plants by hand.
Dabbing individual pests with an alcohol-soaked cotton swab or neem-based leaf shine will also work when infestations are light.
Commercially available beneficial insects, such as ladybugs and lacewing, are natural predators of the young larval or “crawler” stage.
Organic pesticides, like insecticidal soap and d-Limonene can also be used to kill the larvae. However, these products have very little persistence in the environment, so several applications during egg-hatching will be required for effective control.
Azamax contains azadirachtin, the key insecticidal ingredient found in neem oil. This concentrated spray is approved for organic use and offers multiple modes of action, making it virtually impossible for pest resistance to develop. Best of all, it’s non-toxic to honey bees and many other beneficial insects.
Horticultural oils and other safe, oil-based insecticides work by smothering insects and will control all pest stages, including adults which are protected from most other insecticides by their armor coverings.
Fast-acting botanical insecticides should be used as a last resort. Derived from plants which have insecticidal properties, these natural pesticides have fewer harmful side effects than synthetic chemicals and break down more quickly in the environment.
0
0
文章
Dummer. ゛☀
2017年09月15日
Pathogen-caused leaf spot diseases, particularly those of stone fruit trees and such vegetables as tomatoes, peppers and lettuce are of two types, those caused by bacteria and those caused by fungus. Leaf spotting of either kind is generally similar in appearance and effect. Prevention and treatment of both kinds often involve the same practices.
Symptoms
Infected plants have brown or black water-soaked spots on the foliage, sometimes with a yellow halo, usually uniform in size. The spots enlarge and will run together under wet conditions. Under dry conditions the spots have a speckled appearance. As spots become more numerous, entire leaves may yellow, wither and drop. Members of the Prunus family (stone fruits, including cherry, plum, almond, apricot and peach) are particularly susceptible to bacterial leaf spot. The fruit may appear spotted or have sunken brown areas. Bacterial leaf spot will also attack tomato and pepper crops in vegetable gardens.
Fungal leaf spot attacks lettuce and can also occur on brassicas and other vegetables including such as cabbage, cauliflower, Chinese cabbage, broccoli, Brussels sprouts, kohlrabi, kale, turnip and rutabaga. For more on vegetables susceptible to bacterial and fungal leaf spot, go here.
Bacterial leaf spot will also infect some annual and perennial flowering plants including geraniums, zinnias, purple cone flowers and black-eyed Susan. Fungal leaf spot will infect aspen and poplar trees. Leaf spot will also cause problems for strawberry plants.
Both types of leaf spot are most active when there is plenty of moisture and warm temperatures. During the summer months, especially if plants are watered by overhead sprinklers, sufficient moisture may be present for infection when the bacteria are splashed or blown on to leaves. Wind and rain transmit the bacteria to plants.
This disease overwinters in the soil around infected plants as well as on garden debris and seeds. It will also remain in the twig cankers, leaves, stems and fruit of infected trees.
Control
When selecting fruit trees, choose resistant varieties if possible.
Keep the soil under the tree clean and rake up fallen fruit.
Use a thick layer of mulch to cover the soil after you have raked and cleaned it well. Mulch will reduce weeds and prevent the disease pathogen from splashing back up onto the leaves.
Prune or stake plants to improve air circulation. Make sure to disinfect your pruning equipment (one part bleach to 4 parts water) after each cut.
Leaf spot among vegetables is most often introduced through infected seed or transplants. Make sure your seeds and transplants are from leaf spot-free stock.
There is no cure for plants infected with bacterial leaf spot. Preventive, organic measures include:
Spraying with a baking soda solution (a tablespoon of baking soda, 2 1/2 tablespoons of vegetable oil, a teaspoon of liquid soap, not detergent, to one gallon of water), or neem oil (do not use when pollinating insects including bees or other beneficial insects are present). Baking soda may burn some plant leaves. Spray only a few and then check for a reaction before applying applications every two weeks.
Apply sulfur sprays or copper-based fungicides weekly at first sign of disease to prevent its spread. These organic fungicides will not kill leaf spot, but prevent the spores from germinating.
Safely treat most fungal and bacterial diseases with SERENADE Garden. This broad spectrum bio-fungicide uses a patented strain of Bacillus subtilis that is registered for organic use. Best of all, SERENADE is completely non-toxic to honey bees and beneficial insects.
Containing copper and pyrethrins, Bonide® Garden Dust is a safe, one-step control for many insect attacks and fungal problems. For best results, cover both the tops and undersides of leaves with a thin uniform film or dust. Depending on foliage density, 10 oz will cover 625 sq ft. Repeat applications every 7-10 days, as needed.
Symptoms
Infected plants have brown or black water-soaked spots on the foliage, sometimes with a yellow halo, usually uniform in size. The spots enlarge and will run together under wet conditions. Under dry conditions the spots have a speckled appearance. As spots become more numerous, entire leaves may yellow, wither and drop. Members of the Prunus family (stone fruits, including cherry, plum, almond, apricot and peach) are particularly susceptible to bacterial leaf spot. The fruit may appear spotted or have sunken brown areas. Bacterial leaf spot will also attack tomato and pepper crops in vegetable gardens.
Fungal leaf spot attacks lettuce and can also occur on brassicas and other vegetables including such as cabbage, cauliflower, Chinese cabbage, broccoli, Brussels sprouts, kohlrabi, kale, turnip and rutabaga. For more on vegetables susceptible to bacterial and fungal leaf spot, go here.
Bacterial leaf spot will also infect some annual and perennial flowering plants including geraniums, zinnias, purple cone flowers and black-eyed Susan. Fungal leaf spot will infect aspen and poplar trees. Leaf spot will also cause problems for strawberry plants.
Both types of leaf spot are most active when there is plenty of moisture and warm temperatures. During the summer months, especially if plants are watered by overhead sprinklers, sufficient moisture may be present for infection when the bacteria are splashed or blown on to leaves. Wind and rain transmit the bacteria to plants.
This disease overwinters in the soil around infected plants as well as on garden debris and seeds. It will also remain in the twig cankers, leaves, stems and fruit of infected trees.
Control
When selecting fruit trees, choose resistant varieties if possible.
Keep the soil under the tree clean and rake up fallen fruit.
Use a thick layer of mulch to cover the soil after you have raked and cleaned it well. Mulch will reduce weeds and prevent the disease pathogen from splashing back up onto the leaves.
Prune or stake plants to improve air circulation. Make sure to disinfect your pruning equipment (one part bleach to 4 parts water) after each cut.
Leaf spot among vegetables is most often introduced through infected seed or transplants. Make sure your seeds and transplants are from leaf spot-free stock.
There is no cure for plants infected with bacterial leaf spot. Preventive, organic measures include:
Spraying with a baking soda solution (a tablespoon of baking soda, 2 1/2 tablespoons of vegetable oil, a teaspoon of liquid soap, not detergent, to one gallon of water), or neem oil (do not use when pollinating insects including bees or other beneficial insects are present). Baking soda may burn some plant leaves. Spray only a few and then check for a reaction before applying applications every two weeks.
Apply sulfur sprays or copper-based fungicides weekly at first sign of disease to prevent its spread. These organic fungicides will not kill leaf spot, but prevent the spores from germinating.
Safely treat most fungal and bacterial diseases with SERENADE Garden. This broad spectrum bio-fungicide uses a patented strain of Bacillus subtilis that is registered for organic use. Best of all, SERENADE is completely non-toxic to honey bees and beneficial insects.
Containing copper and pyrethrins, Bonide® Garden Dust is a safe, one-step control for many insect attacks and fungal problems. For best results, cover both the tops and undersides of leaves with a thin uniform film or dust. Depending on foliage density, 10 oz will cover 625 sq ft. Repeat applications every 7-10 days, as needed.
0
0
文章
Dummer. ゛☀
2017年09月14日
Sometimes called jumping plant lice, psyllids feed on a variety of plants including most fruit trees and small fruits as well as tomato and potato. Both adults and nymphs feed by piercing the leaf surface and extracting cell sap. This causes foliage (especially the upper leaves) to turn yellow, curl and eventually die. Honeydew secreted by the psyllids encourages the growth of dark sooty molds. Many species transmit disease-carrying viruses.
Adults (1/10 inch long) are reddish brown in color with transparent wings and strong jumping legs. They are very active and will hop or fly away when disturbed. Nymphs are flat and elliptical in shape, almost scale-like. They are less active than adults and are most numerous on the undersides of leaves. Newly hatched nymphs are yellowish in color but turn green as they mature.
Note: Psyllids are monophagous which means that they are host specific (each species feeds on only one plant type).
Life Cycle
Adults overwinter in crevices on tree trunks. In early spring they mate and females begin depositing orange-yellow eggs in the crevices about the buds, and after the foliage is out, on the leaves. Hatching occurs in 4-15 days. Yellow to green nymphs pass through five in instars in 2-3 weeks before reaching the adult stage. There are one to five generations per year depending on species.
Psyllid Control
To get rid of psyllids spray horticultural oil in early spring to destroy overwintering adults and eggs.
Beneficial insects, such as ladybugs and lacewing, are important natural predators of this pest. For best results, make releases when pest levels are low to medium.
If populations are high, use a least-toxic, short-lived natural pesticide to establish control, then release predatory insects to maintain control.
Diatomaceous earth contains no toxic poisons and works quickly on contact. Dust lightly and evenly over vegetable crops wherever adults are found.
Safer® Insecticidal Soap will work fast on heavy infestations. A short-lived natural pesticide, it works by damaging the outer layer of soft-bodied insect pests, causing dehydration and death within hours. Apply 2.5 oz/ gallon of water when insects are present, repeat every 7-10 day as needed.
Surround WP (kaolin clay) forms a protective barrier film, which acts as a broad spectrum crop protectant for preventing damage from insect pests.
70% Neem Oil is approved for organic use and can be sprayed on vegetables, fruit trees and flowers to kill eggs, larvae and adult insects. Mix 1 oz/ gallon of water and spray all leaf surfaces (including the undersides of leaves) until completely wet.
If pest levels become intolerable, spot treat with insecticides approved for organic use every 5-7 days. Thorough coverage of both upper and lower infested leaves is necessary for effective control.
Adults (1/10 inch long) are reddish brown in color with transparent wings and strong jumping legs. They are very active and will hop or fly away when disturbed. Nymphs are flat and elliptical in shape, almost scale-like. They are less active than adults and are most numerous on the undersides of leaves. Newly hatched nymphs are yellowish in color but turn green as they mature.
Note: Psyllids are monophagous which means that they are host specific (each species feeds on only one plant type).
Life Cycle
Adults overwinter in crevices on tree trunks. In early spring they mate and females begin depositing orange-yellow eggs in the crevices about the buds, and after the foliage is out, on the leaves. Hatching occurs in 4-15 days. Yellow to green nymphs pass through five in instars in 2-3 weeks before reaching the adult stage. There are one to five generations per year depending on species.
Psyllid Control
To get rid of psyllids spray horticultural oil in early spring to destroy overwintering adults and eggs.
Beneficial insects, such as ladybugs and lacewing, are important natural predators of this pest. For best results, make releases when pest levels are low to medium.
If populations are high, use a least-toxic, short-lived natural pesticide to establish control, then release predatory insects to maintain control.
Diatomaceous earth contains no toxic poisons and works quickly on contact. Dust lightly and evenly over vegetable crops wherever adults are found.
Safer® Insecticidal Soap will work fast on heavy infestations. A short-lived natural pesticide, it works by damaging the outer layer of soft-bodied insect pests, causing dehydration and death within hours. Apply 2.5 oz/ gallon of water when insects are present, repeat every 7-10 day as needed.
Surround WP (kaolin clay) forms a protective barrier film, which acts as a broad spectrum crop protectant for preventing damage from insect pests.
70% Neem Oil is approved for organic use and can be sprayed on vegetables, fruit trees and flowers to kill eggs, larvae and adult insects. Mix 1 oz/ gallon of water and spray all leaf surfaces (including the undersides of leaves) until completely wet.
If pest levels become intolerable, spot treat with insecticides approved for organic use every 5-7 days. Thorough coverage of both upper and lower infested leaves is necessary for effective control.
0
0
