文章
Dummer. ゛☀
2017年09月15日
Wilting plants and yellow/brown patches on lawns.
Plants affected
Leatherjackets mainly attack grass roots. They will also feed on cereal crops and burrow into potato tubers.
About Leatherjackets
Leatherjackets are the larval stage of crane flies.
Crane flies, also known as daddy-long-legs, have long thin legs, one pair of wings and a small thin body around 2.5cm long.
Males and females can be identified by comparing the tip of their abdomens: males - are blunt whilst females - are pointed.
Adults are commonly seen flying from late August to October.
Since adults do not feed they cause no plant damage.
Mating and egg laying takes place within 24 hours of adults emerging.
Females lay their eggs by 'hopping' on the soil surface. Each time they land they insert their pointed abdomen into the soil and deposit an egg.
The larvae emerge as small brown grubs. They will begin feeding on root structures of grasses.
During the day the larvae remain under the soil, but on wet nights may appear above the surface and feed on plant stems.
Larvae overwinter in the soil until spring, when they begin feeding again.
There are four stages of larval development.
When they reach full size larvae they can be up to 4cm in length.
They pupate in August.
The pupae have rows of spines along their sides which enable them to move up and down within the soil during wet and dry periods.
Treatment
Organic
Regular and thorough observation of lawns and plants is essential when wishing to control leatherjackets organically.
Remove by covering small areas of lawn with black polythene overnight after heavy rain or irrigation. The grubs will come up onto the grass and can be removed in the morning.
Natural enemies can be released onto the affected plants.
The parasitic nematode Steinernema feltiae can be watered into the ground around affected areas. These parasites infect the grubs with bacteria to kill them.
Compacting the soil using a heavy roller will make it harder for the grubs to move through it.
Prevention
Regularly check lawns and plants for signs of leatherjacket infestation and deal with them as soon as they appear.
Encourage insect-eating birds by hanging feeders in the winter months and nest boxes in the spring.
Plants affected
Leatherjackets mainly attack grass roots. They will also feed on cereal crops and burrow into potato tubers.
About Leatherjackets
Leatherjackets are the larval stage of crane flies.
Crane flies, also known as daddy-long-legs, have long thin legs, one pair of wings and a small thin body around 2.5cm long.
Males and females can be identified by comparing the tip of their abdomens: males - are blunt whilst females - are pointed.
Adults are commonly seen flying from late August to October.
Since adults do not feed they cause no plant damage.
Mating and egg laying takes place within 24 hours of adults emerging.
Females lay their eggs by 'hopping' on the soil surface. Each time they land they insert their pointed abdomen into the soil and deposit an egg.
The larvae emerge as small brown grubs. They will begin feeding on root structures of grasses.
During the day the larvae remain under the soil, but on wet nights may appear above the surface and feed on plant stems.
Larvae overwinter in the soil until spring, when they begin feeding again.
There are four stages of larval development.
When they reach full size larvae they can be up to 4cm in length.
They pupate in August.
The pupae have rows of spines along their sides which enable them to move up and down within the soil during wet and dry periods.
Treatment
Organic
Regular and thorough observation of lawns and plants is essential when wishing to control leatherjackets organically.
Remove by covering small areas of lawn with black polythene overnight after heavy rain or irrigation. The grubs will come up onto the grass and can be removed in the morning.
Natural enemies can be released onto the affected plants.
The parasitic nematode Steinernema feltiae can be watered into the ground around affected areas. These parasites infect the grubs with bacteria to kill them.
Compacting the soil using a heavy roller will make it harder for the grubs to move through it.
Prevention
Regularly check lawns and plants for signs of leatherjacket infestation and deal with them as soon as they appear.
Encourage insect-eating birds by hanging feeders in the winter months and nest boxes in the spring.
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文章
Dummer. ゛☀
2017年09月15日
Distorted, yellowing or slowed growth on plants can often be a sign of scale insects. These look like tiny brown or orange blobs and can often be found on the undersides of the leaves near the veins, on the stems or in the leaf joints. They produce sticky honeydew as they feed which can cause the foliage on infested plants to become sticky and covered with dark sooty mould.
Plants affected
Scales are usually pests of ornamental plants and can be especially troublesome in greenhouses. Over 300 species of ornamental plants are known hosts.
About Scale insects
Scale insects are small sap-sucking insects, so called because they produce an umbrella-like waxy coating or 'scale' over their soft bodies.
They're often difficult to detect on plants, although leaf yellowing or sticky honeydew deposits can be the first signs of infestation.
Scale insects may appear as small, flattened white, yellow or brown 'discs' or 'blobs', on stems or on the underside of leaves near the veins.
Scale insects are divided into two families - soft scale (Coccidae) and hard scale (Diaspididae).
Soft scales can breed all year round on protected crops and produce large amounts of sugary honeydew when they feed on the plant's sap. This honeydew attracts sooty moulds that grow on the leaves.
Hard scales lay eggs under their scales which hatch into nymphs or 'crawlers' after the female dies in early summer.
The nymphs can move short distances on a plant, but disperse long distances on the wind or on animals.
Hard scale don't produce large amounts of honeydew.
Female scale insect nymphs become immobile once they find a suitable feeding site and become adults.
Males are rarely seen but are often winged and midge-like in appearance.
The 'scale' produced by these insects can remain on a plant for a long time after they're dead.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Scale insects
Pyrethrum
Natural fatty acids
Rape seed oil
Tar oil wash (for use on deciduous trees and roses in December)
Thiacloprid (for use with outdoor fruit crops)
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Check bought plants thoroughly. If an infestation is in the early stages, the scales can be cleaned off using a brush and water, or just a thumbnail.
Biological control is available in the form of a tiny wasp which parasitises soft scales, Metaphycus helvolus. This can be purchased for release into the greenhouse but requires good light and temperatures of at least 22°C (72°F) to be effective.
The small predatory ladybird Chilocorus nigritus can also be purchased, that feeds on hard scale species. Lacewing larvae also control scale.
Prevention
Check plants regularly for signs of scale infestation and deal with them as soon as they appear.
Keep the environment clear of weeds because these often harbour the pest.
Monitor plants for signs of scale, such as leaf drop, honeydew or sooty mould.
Look out for ants running up and down the plants, 'milking' the honeydew.
Avoid using broad spectrum insecticides which will kill beneficial insects as well as scale.
Destroy any leaves that have been removed from an infested plant because these can harbour many mobile juvenile scales.
Plants affected
Scales are usually pests of ornamental plants and can be especially troublesome in greenhouses. Over 300 species of ornamental plants are known hosts.
About Scale insects
Scale insects are small sap-sucking insects, so called because they produce an umbrella-like waxy coating or 'scale' over their soft bodies.
They're often difficult to detect on plants, although leaf yellowing or sticky honeydew deposits can be the first signs of infestation.
Scale insects may appear as small, flattened white, yellow or brown 'discs' or 'blobs', on stems or on the underside of leaves near the veins.
Scale insects are divided into two families - soft scale (Coccidae) and hard scale (Diaspididae).
Soft scales can breed all year round on protected crops and produce large amounts of sugary honeydew when they feed on the plant's sap. This honeydew attracts sooty moulds that grow on the leaves.
Hard scales lay eggs under their scales which hatch into nymphs or 'crawlers' after the female dies in early summer.
The nymphs can move short distances on a plant, but disperse long distances on the wind or on animals.
Hard scale don't produce large amounts of honeydew.
Female scale insect nymphs become immobile once they find a suitable feeding site and become adults.
Males are rarely seen but are often winged and midge-like in appearance.
The 'scale' produced by these insects can remain on a plant for a long time after they're dead.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Scale insects
Pyrethrum
Natural fatty acids
Rape seed oil
Tar oil wash (for use on deciduous trees and roses in December)
Thiacloprid (for use with outdoor fruit crops)
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Check bought plants thoroughly. If an infestation is in the early stages, the scales can be cleaned off using a brush and water, or just a thumbnail.
Biological control is available in the form of a tiny wasp which parasitises soft scales, Metaphycus helvolus. This can be purchased for release into the greenhouse but requires good light and temperatures of at least 22°C (72°F) to be effective.
The small predatory ladybird Chilocorus nigritus can also be purchased, that feeds on hard scale species. Lacewing larvae also control scale.
Prevention
Check plants regularly for signs of scale infestation and deal with them as soon as they appear.
Keep the environment clear of weeds because these often harbour the pest.
Monitor plants for signs of scale, such as leaf drop, honeydew or sooty mould.
Look out for ants running up and down the plants, 'milking' the honeydew.
Avoid using broad spectrum insecticides which will kill beneficial insects as well as scale.
Destroy any leaves that have been removed from an infested plant because these can harbour many mobile juvenile scales.
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文章
Dummer. ゛☀
2017年09月15日
Stunted and deformed foliage, collapsed plants, swollen and distorted roots. The foliage may develop a purple tinge and wilt easily on hot dry days.
Plants affected
Members of the brassica family, including cabbages, Brussels sprouts, broccoli, cauliflower, swede, wallflowers, and related weeds.
About
Clubroot exists as spores in the soil and can survive for at least 20 years, waiting for a suitable plant to infect.
The spores enter plants through the roots.
Once inside the roots, more spores are produced which end up back in the soil when the infected plant ultimately rots away.
The disease can be easily transported to new sites in soil or on muddy boots or plant material.
Treatment
Preventing the disease from entering your garden is by far the most important consideration when dealing with clubroot.
Take care when buying brassica plants, especially when you’re not sure where they come from. For example those sold at car boot sales and small plant fairs.
Aim to grow all new brassicas from seed.
Clean tools, pots and boots carefully after use on contaminated ground.
Affected plants should be removed entirely once harvested, dried and then burned.
Some control of the symptoms is possible by liming the soil to raise the pH to around 7.
Keep your garden clear of related weeds which can harbour the disease. These include wild radish and shepherd’s purse.
Some varieties are more resistant to clubroot than others. Good choices include: Cabbage ‘Kilaxy’, Cauliflower ‘Clapton’, Brussels sprout ‘Crispus’ and Swede ‘Gowrie’
Plants affected
Members of the brassica family, including cabbages, Brussels sprouts, broccoli, cauliflower, swede, wallflowers, and related weeds.
About
Clubroot exists as spores in the soil and can survive for at least 20 years, waiting for a suitable plant to infect.
The spores enter plants through the roots.
Once inside the roots, more spores are produced which end up back in the soil when the infected plant ultimately rots away.
The disease can be easily transported to new sites in soil or on muddy boots or plant material.
Treatment
Preventing the disease from entering your garden is by far the most important consideration when dealing with clubroot.
Take care when buying brassica plants, especially when you’re not sure where they come from. For example those sold at car boot sales and small plant fairs.
Aim to grow all new brassicas from seed.
Clean tools, pots and boots carefully after use on contaminated ground.
Affected plants should be removed entirely once harvested, dried and then burned.
Some control of the symptoms is possible by liming the soil to raise the pH to around 7.
Keep your garden clear of related weeds which can harbour the disease. These include wild radish and shepherd’s purse.
Some varieties are more resistant to clubroot than others. Good choices include: Cabbage ‘Kilaxy’, Cauliflower ‘Clapton’, Brussels sprout ‘Crispus’ and Swede ‘Gowrie’
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文章
Dummer. ゛☀
2017年09月15日
Yellow/ brown patches on lawns. Wilting plants and damaged leaves on garden shrubs, vegetables and immature trees.
Plants affected
Chafer larvae attack the roots of lawns and some ornamental plants, fruit and vegetables, while adult chafers feed on the leaves of a range of different shrubs, plants and immature deciduous trees. However the adults rarely cause much damage.
About Chafer grubs
Adult chafers range in size, the biggest at 30mm in length being the Cockchafer, and the smallest the Welsh chafer at 11mm.
The adult chafers are mainly reddish brown in colour with distinctive large antennae.
Chafers have strong, hard cases that protect their delicate wings, when in flight these cases make a distinctive whirring sound.
The creamy, white larvae or grubs are often found curled up just below the soil surface, feeding especially on roots, mainly in August and September.
Larvae have distinctive grey ends to their abdomens, and brown heads.
Some species remain as larvae for up to three years.
Plant damage is mostly caused by the larvae although the adults can also seriously damage the upper parts of the plants.
Chafers overwinter below ground as pupae and the adults emerge in spring.
Adults often return to the same location to lay their eggs over a two week period during early summer.
Chafer predators such as foxes, badgers, rooks, crows, jays and magpies often damage lawns and community greens searching for grubs.
Treatment
Organic
Try natural pest controls, such as the parasitic nematode, Heterorhabditis megidis.
Where possible eradicate the larval stages by lifting sections of turf and disposing of the larvae.
Encourage birds that prey on the beetles and their larvae.
Use barrier methods such as fleece, to keep adults away from plants at risk.
Prevention
Check regularly for signs of chafer infestation and quickly deal with them.
Scarify and aerate lawns in autumn.
Where lawns have a history of infestation try to compress the turf by rolling it heavily during spring.
Plants affected
Chafer larvae attack the roots of lawns and some ornamental plants, fruit and vegetables, while adult chafers feed on the leaves of a range of different shrubs, plants and immature deciduous trees. However the adults rarely cause much damage.
About Chafer grubs
Adult chafers range in size, the biggest at 30mm in length being the Cockchafer, and the smallest the Welsh chafer at 11mm.
The adult chafers are mainly reddish brown in colour with distinctive large antennae.
Chafers have strong, hard cases that protect their delicate wings, when in flight these cases make a distinctive whirring sound.
The creamy, white larvae or grubs are often found curled up just below the soil surface, feeding especially on roots, mainly in August and September.
Larvae have distinctive grey ends to their abdomens, and brown heads.
Some species remain as larvae for up to three years.
Plant damage is mostly caused by the larvae although the adults can also seriously damage the upper parts of the plants.
Chafers overwinter below ground as pupae and the adults emerge in spring.
Adults often return to the same location to lay their eggs over a two week period during early summer.
Chafer predators such as foxes, badgers, rooks, crows, jays and magpies often damage lawns and community greens searching for grubs.
Treatment
Organic
Try natural pest controls, such as the parasitic nematode, Heterorhabditis megidis.
Where possible eradicate the larval stages by lifting sections of turf and disposing of the larvae.
Encourage birds that prey on the beetles and their larvae.
Use barrier methods such as fleece, to keep adults away from plants at risk.
Prevention
Check regularly for signs of chafer infestation and quickly deal with them.
Scarify and aerate lawns in autumn.
Where lawns have a history of infestation try to compress the turf by rolling it heavily during spring.
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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.
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文章
Dummer. ゛☀
2017年09月15日
Large holes in the leaves of brassica crops and nasturtiums are usually the work of cabbage white caterpillars. Before an attack you may notice large numbers of white buttlerflies around your plants, as they lay eggs. These hatch into larvae which make small holes in the leaves as they start to feed on them, becoming much larger as the caterpillars start to feed more vigorously. Caterpillars also produce small brown or dark green granular deposits as they feed.
Plants affected
All types of brassica are affected by cabbage white caterpillars, including cabbages, cauliflower, Brussels sprouts, swede and turnips.
About Cabbage white butterflies
The caterpillars of a few species of butterflies can cause extensive damage to cabbages and other brassicas, eating holes in leaves and tunnelling into the hearts. Plants begin to rot and become spoiled with excrement.
Two species are particularly important pests: the large white butterfly, Pieris brassicae, and the Small White butterfly Pieris rapae.
Both species are commonly seen flying within our gardens and are affectionately called summer snowflakes.
While the small white is a native species, the large white has usually migrated from southern Europe becasue they don't often survive a north European winter.
Large white butterflies have often been seen crossing the English channel in swarms of many hundred individuals.
Cabbage white butterflies overwinter as pupae. Those that survive the cold months will hatch into butterflies during the spring.
The butterflies mate then each female lays a few hundred eggs, on the leaves of cabbages, other related plants and nasturtiums.
The large white's eggs are often laid in batches of ten to 20,which hatch into yellow and black slightly hairy caterpillars in about two weeks.
Large white caterpillars feed for a month or more and can reach 50mm in length before they turn into pupae.
The small white's eggs are laid singly and hatch into bright velvety-green caterpillars. Unlike the large white, these caterpillars often burrow into the hearts of cabbages to feed.
Cabbage white caterpillars leave their food plants when ready to pupate and usually attach themselves to a vertical surface such as a fence or wall with a silk girdle before their final skin shed.
During the summer months, the pupae soon hatch into the next generation of butterflies and the cycle continues.
The severity of cabbage white problems can vary considerably from year to year due to weather, immigration and diseases.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Cabbage white butterflies
Pyrethrum
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Inspect the undersides of leaves and remove any egg clusters.
Remove caterpillars by hand, particularly before cabbages begin to develop hearts.
Encourage insectivorous birds within the garden by using bird-feeders in winter and nest boxes in spring.
Don't remove dead older caterpillars that have become parasitised because these will produce many more parasites that will attack and kill further generations of caterpillars.
A naturally occurring bacterium, Bacillus thuringiensis, kills only caterpillars and not the predatory insects, and is very effective when sprayed thoroughly above and below leaves.
Prevention
Inspect susceptible plants on a daily basis during the growing season and remove any eggs or caterpillars that are found. The appearance of white butterflies hovering around susceptible plants almost certainly means that eggs have been laid.
Cover plants with insect-proof mesh or fleece, although this can lead to overheating during the warmer summer days.
Transfer any parasitised caterpillars to plants where new caterpillar infestations are expected.
Avoid planting colourful, high nectar plants near the cabbage patch as these will encourage adult butterflies into the garden.
Plants affected
All types of brassica are affected by cabbage white caterpillars, including cabbages, cauliflower, Brussels sprouts, swede and turnips.
About Cabbage white butterflies
The caterpillars of a few species of butterflies can cause extensive damage to cabbages and other brassicas, eating holes in leaves and tunnelling into the hearts. Plants begin to rot and become spoiled with excrement.
Two species are particularly important pests: the large white butterfly, Pieris brassicae, and the Small White butterfly Pieris rapae.
Both species are commonly seen flying within our gardens and are affectionately called summer snowflakes.
While the small white is a native species, the large white has usually migrated from southern Europe becasue they don't often survive a north European winter.
Large white butterflies have often been seen crossing the English channel in swarms of many hundred individuals.
Cabbage white butterflies overwinter as pupae. Those that survive the cold months will hatch into butterflies during the spring.
The butterflies mate then each female lays a few hundred eggs, on the leaves of cabbages, other related plants and nasturtiums.
The large white's eggs are often laid in batches of ten to 20,which hatch into yellow and black slightly hairy caterpillars in about two weeks.
Large white caterpillars feed for a month or more and can reach 50mm in length before they turn into pupae.
The small white's eggs are laid singly and hatch into bright velvety-green caterpillars. Unlike the large white, these caterpillars often burrow into the hearts of cabbages to feed.
Cabbage white caterpillars leave their food plants when ready to pupate and usually attach themselves to a vertical surface such as a fence or wall with a silk girdle before their final skin shed.
During the summer months, the pupae soon hatch into the next generation of butterflies and the cycle continues.
The severity of cabbage white problems can vary considerably from year to year due to weather, immigration and diseases.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Cabbage white butterflies
Pyrethrum
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Inspect the undersides of leaves and remove any egg clusters.
Remove caterpillars by hand, particularly before cabbages begin to develop hearts.
Encourage insectivorous birds within the garden by using bird-feeders in winter and nest boxes in spring.
Don't remove dead older caterpillars that have become parasitised because these will produce many more parasites that will attack and kill further generations of caterpillars.
A naturally occurring bacterium, Bacillus thuringiensis, kills only caterpillars and not the predatory insects, and is very effective when sprayed thoroughly above and below leaves.
Prevention
Inspect susceptible plants on a daily basis during the growing season and remove any eggs or caterpillars that are found. The appearance of white butterflies hovering around susceptible plants almost certainly means that eggs have been laid.
Cover plants with insect-proof mesh or fleece, although this can lead to overheating during the warmer summer days.
Transfer any parasitised caterpillars to plants where new caterpillar infestations are expected.
Avoid planting colourful, high nectar plants near the cabbage patch as these will encourage adult butterflies into the garden.
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文章
Dummer. ゛☀
2017年09月15日
Mature plants can exhibit wilting, discoloured leaves. Younger and newly transplanted plants can show slower growth, and may eventually be killed.
Plants affected
Virtually all Brassica plants are attacked as well as some ornamentals.
About
Adults are similar in appearance and size to common house flies.
Larvae are white, legless grubs up to 1cm long, and can be found in the soil around plant roots.
Pupae are reddish brown, and are also found in the soil.
After over-wintering, adults emerge from pupal cases in late April / May to mate, and lay small white eggs in the soil at the base of plants.
Eggs will hatch in about a week and the tiny white larvae will begin feeding on the roots of susceptible plants.
After around a month of feeding, the larvae will pupate below the soil surface.
A second generation of adults will emerge in June / July, and a third later in the autumn.
Damage to older plants from larval feeding rarely results in death, although yields may be reduced.
Treatment
Organic
Regularly cultivate soil to expose larvae and pupae to predators. Chickens are particularly good for this, if you have access to them. Allow them onto the land during the winter, when they will happily consume the larvae.
Encourage insectivorous birds by hanging boxes and feeders.
Encourage predatory ground beetles by providing suitable winter shelters.
Prevention
Fleeces and netting can be used around bedding plants to prevent flies laying eggs. Alternatively, lay 15cm discs of carpet, plastic or cardboard around the base of plants.
Use sticky traps around plants to trap adults, and to monitor the first signs of pest presence.
A four year crop rotation will help stop larvae populations from building up in the soil. In simple terms, after growing brassicas, do not grow more brassicas in the same place for at least four years.
Plants affected
Virtually all Brassica plants are attacked as well as some ornamentals.
About
Adults are similar in appearance and size to common house flies.
Larvae are white, legless grubs up to 1cm long, and can be found in the soil around plant roots.
Pupae are reddish brown, and are also found in the soil.
After over-wintering, adults emerge from pupal cases in late April / May to mate, and lay small white eggs in the soil at the base of plants.
Eggs will hatch in about a week and the tiny white larvae will begin feeding on the roots of susceptible plants.
After around a month of feeding, the larvae will pupate below the soil surface.
A second generation of adults will emerge in June / July, and a third later in the autumn.
Damage to older plants from larval feeding rarely results in death, although yields may be reduced.
Treatment
Organic
Regularly cultivate soil to expose larvae and pupae to predators. Chickens are particularly good for this, if you have access to them. Allow them onto the land during the winter, when they will happily consume the larvae.
Encourage insectivorous birds by hanging boxes and feeders.
Encourage predatory ground beetles by providing suitable winter shelters.
Prevention
Fleeces and netting can be used around bedding plants to prevent flies laying eggs. Alternatively, lay 15cm discs of carpet, plastic or cardboard around the base of plants.
Use sticky traps around plants to trap adults, and to monitor the first signs of pest presence.
A four year crop rotation will help stop larvae populations from building up in the soil. In simple terms, after growing brassicas, do not grow more brassicas in the same place for at least four years.
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文章
Dummer. ゛☀
2017年09月15日
Waxy residues and small white skin sheds on leaves and heads of many brassicas and cabbage family plants. There may be a covering of a sticky, sugary substance on the leaves which could become infected with sooty mould. Leaves may become yellow with high infestations. Dense colonies of aphids may be found on the undersides of older leaves.
Plants affected
Cabbages, cauliflowers, kale, rape, spinach, Brussels sprouts, turnips, broccoli, mustard, other cabbage family crops, radishes, swedes and some weeds.
About Mealy cabbage aphid
Aphids are usually found on the youngest leaves and shoots, or on the heads of cabbages.
The undersides of more mature leaves will also be affected when infestations are large.
Adult aphids are up to 2mm long and elliptical in shape. They are mainly green in colour although their waxy coating gives them a powdery grey appearance.
During the warmer months aphids give birth to as many as five live young a day so rapidly produce large colonies.
When the colonies become over populated, they move to different locations by producing winged aphids.
During the autumn, aphids mate and produce eggs which overwinter.
Mealy cabbage aphids can damage plants in two ways, either directly by piercing the leaf with their feeding tubes and sucking the sap, or indirectly by infecting the plant with a virus.
Aphid-transmitted viruses can often result in deformed and stunted plants.
Aphids feed on plant sap, and excrete plant sugars as honeydew
Honeydew often covers the leaves of a plant and then becomes infected with unsightly black sooty moulds.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Mealy cabbage aphid
Pyrethroids and Pyrethrin
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Regular and thorough observation of plants.
Spray infested areas with a firm jet of water.
Spray with natural fatty acids, for example insecticidal soap.
Netting and fleece can be used to stop the aphids spreading.
For outdoor plants, aphid predators such as ladybirds, hoverflies, lacewing larvae and parasitic midges called aphidoletes, can be released onto affected plants.
For greenhouse plants in a contained environment, parasitic wasps such as Aphidius colemani and Aphidius ervi can be used.
Prevention
Regularly check plants for signs of aphid infestation and deal with them as soon as they appear.
Encourage natural enemies like ladybirds, hoverflies and lacewings to become established in the garden by planting daisy-like flowers, yellow flowers and in particular, the poached egg plant Limnanthes douglasii.
Avoid using broad spectrum insecticides which will kill beneficial insects as well as aphids.
Encourage insect-eating birds such as blue tits, by hanging feeders during the winter months and nest boxes in the spring.
Maintain a weed-free environment around the brassica plants and collect and destroy all shed leaves.
Plants affected
Cabbages, cauliflowers, kale, rape, spinach, Brussels sprouts, turnips, broccoli, mustard, other cabbage family crops, radishes, swedes and some weeds.
About Mealy cabbage aphid
Aphids are usually found on the youngest leaves and shoots, or on the heads of cabbages.
The undersides of more mature leaves will also be affected when infestations are large.
Adult aphids are up to 2mm long and elliptical in shape. They are mainly green in colour although their waxy coating gives them a powdery grey appearance.
During the warmer months aphids give birth to as many as five live young a day so rapidly produce large colonies.
When the colonies become over populated, they move to different locations by producing winged aphids.
During the autumn, aphids mate and produce eggs which overwinter.
Mealy cabbage aphids can damage plants in two ways, either directly by piercing the leaf with their feeding tubes and sucking the sap, or indirectly by infecting the plant with a virus.
Aphid-transmitted viruses can often result in deformed and stunted plants.
Aphids feed on plant sap, and excrete plant sugars as honeydew
Honeydew often covers the leaves of a plant and then becomes infected with unsightly black sooty moulds.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Mealy cabbage aphid
Pyrethroids and Pyrethrin
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Regular and thorough observation of plants.
Spray infested areas with a firm jet of water.
Spray with natural fatty acids, for example insecticidal soap.
Netting and fleece can be used to stop the aphids spreading.
For outdoor plants, aphid predators such as ladybirds, hoverflies, lacewing larvae and parasitic midges called aphidoletes, can be released onto affected plants.
For greenhouse plants in a contained environment, parasitic wasps such as Aphidius colemani and Aphidius ervi can be used.
Prevention
Regularly check plants for signs of aphid infestation and deal with them as soon as they appear.
Encourage natural enemies like ladybirds, hoverflies and lacewings to become established in the garden by planting daisy-like flowers, yellow flowers and in particular, the poached egg plant Limnanthes douglasii.
Avoid using broad spectrum insecticides which will kill beneficial insects as well as aphids.
Encourage insect-eating birds such as blue tits, by hanging feeders during the winter months and nest boxes in the spring.
Maintain a weed-free environment around the brassica plants and collect and destroy all shed leaves.
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文章
Dummer. ゛☀
2017年09月15日
The main symptoms of this prevalent disorder are large, black/brown, leathery sunken pits on the base of fruits. This is especially common on tomatoes and peppers.
Plants affected
Peppers, tomatoes, squashes, aubergines and watermelons. Plants with soft, succulent fruits suffer the worst from this condition.
About Blossom-end rot
Blossom-end rot is not a disease but is the result of a number of environmental and physiological factors.
It's most common for the disorder to arise as the fruits are half way through their development.
The disorder develops if the plant's water intake is not sufficient for example in drought, and consequently the plant cannot extract enough calcium from the soil.
Plants grown in acid soil are at a higher risk of developing these symptoms.
Over-watering can also cause the disorder.
Blossom-end rot can cause considerable fruit/crop damage, sometimes with large areas of the fruit affected.
The rot is not transmittable from plant to plant or fruit to fruit.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Blossom-end rot
Calcium carbonate
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Use Organic fertilisers with added plant nutrients, especially those containing calcium.
Try to maintain a constant soil pH around 6.5.
Prevention
Thorough checks of crops during the fruiting season will reveal the presence of this disorder and enable the growing conditions to be corrected.
Plants affected
Peppers, tomatoes, squashes, aubergines and watermelons. Plants with soft, succulent fruits suffer the worst from this condition.
About Blossom-end rot
Blossom-end rot is not a disease but is the result of a number of environmental and physiological factors.
It's most common for the disorder to arise as the fruits are half way through their development.
The disorder develops if the plant's water intake is not sufficient for example in drought, and consequently the plant cannot extract enough calcium from the soil.
Plants grown in acid soil are at a higher risk of developing these symptoms.
Over-watering can also cause the disorder.
Blossom-end rot can cause considerable fruit/crop damage, sometimes with large areas of the fruit affected.
The rot is not transmittable from plant to plant or fruit to fruit.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Blossom-end rot
Calcium carbonate
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Use Organic fertilisers with added plant nutrients, especially those containing calcium.
Try to maintain a constant soil pH around 6.5.
Prevention
Thorough checks of crops during the fruiting season will reveal the presence of this disorder and enable the growing conditions to be corrected.
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文章
Dummer. ゛☀
2017年09月15日
Colonies of aphids can be found in clusters on soft new growth of a wide variety of plants. Buds, tips of stems and the undersides of leaves are all good places to look. Aphids come in many different colours from common greenfly and blackfly to yellows, browns and whites. Many species are specific to one group of plants but they all need to be dealt with in a similar way.
Plants affected
From time to time, aphids may attack almost any garden plant.
About
Adult aphids are rarely more than 3mm long and are elliptical in shape.
Large colonies can cover areas on the youngest sections of stems, and the undersides of leaves and sometimes on flower-buds.
During the warmer months aphids give birth to as many as five live young a day, so large colonies can develop very quickly.
When the colonies become over-populated, they move to different locations by producing winged aphids.
During the cooler months, aphids mate and produce eggs which over-winter.
Aphids feed on plant sap and excrete plant sugars as honeydew.
Honeydew often covers the leaves of a plant and then becomes infested with black sooty moulds.
Treatment
Chemical
Lambda-cyhalothrin and deltamethrin are both contact insecticides which are effective only when sprayed directly onto the aphids. A suitable systemic insecticide is thiacloprid which is taken in through the leaves and is taken up by the feeding aphids. Naturally occurring insecticides such as pyrethrum and fatty acids can also be used.
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Encourage natural predators such as ladybirds and lacewings and insectivorous birds.
Have patience – when aphid populations peak, predatory insects will soon move in. Often this is when people lose their nerve and turn to sprays and, in doing so, kill all the natural predators too.
Don’t over-feed plants. Too much fertilizer will lead to lots of soft, sappy growth which will encourage aphid attacks.
Consider planting a sacrificial crop near to vegetables. For example, nasturtiums which attract black-fly away from brassicas.
Infestations in greenhouses or conservatories can be effectively treated with a biological control such as ladybird larvae.
Plants affected
From time to time, aphids may attack almost any garden plant.
About
Adult aphids are rarely more than 3mm long and are elliptical in shape.
Large colonies can cover areas on the youngest sections of stems, and the undersides of leaves and sometimes on flower-buds.
During the warmer months aphids give birth to as many as five live young a day, so large colonies can develop very quickly.
When the colonies become over-populated, they move to different locations by producing winged aphids.
During the cooler months, aphids mate and produce eggs which over-winter.
Aphids feed on plant sap and excrete plant sugars as honeydew.
Honeydew often covers the leaves of a plant and then becomes infested with black sooty moulds.
Treatment
Chemical
Lambda-cyhalothrin and deltamethrin are both contact insecticides which are effective only when sprayed directly onto the aphids. A suitable systemic insecticide is thiacloprid which is taken in through the leaves and is taken up by the feeding aphids. Naturally occurring insecticides such as pyrethrum and fatty acids can also be used.
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Encourage natural predators such as ladybirds and lacewings and insectivorous birds.
Have patience – when aphid populations peak, predatory insects will soon move in. Often this is when people lose their nerve and turn to sprays and, in doing so, kill all the natural predators too.
Don’t over-feed plants. Too much fertilizer will lead to lots of soft, sappy growth which will encourage aphid attacks.
Consider planting a sacrificial crop near to vegetables. For example, nasturtiums which attract black-fly away from brassicas.
Infestations in greenhouses or conservatories can be effectively treated with a biological control such as ladybird larvae.
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0
文章
Dummer. ゛☀
2017年09月15日
Look for
Small piles of earth around holes in soil, lawns, paths, and at the base of exterior walls. Adults may be in the house around fresh and stored food, and on sap-sucking pest-infested plants. Large swarms of flying ants appear in late summer.
Plants affected
Garden ants rarely cause damage to plants. However, they feed on sugary foods, oily seeds, honeydew from aphid-infected plants, and other small insects. Heaps of earth around the nest entrance can be a nuisance in the lawn where they interfere with mowing, and they can also partly bury low-growing plants.
About Garden ants
There are two main species of garden ants, the red ant Myrmica rubra and the black ant, Lasius niger.
Queen ants fly in from neighbouring gardens all the time but are killed by ants from existing nests. Killing a queen and her nest simply makes space for another. For this reason it is best to focus on controlling only those nests that are causing real problems.
Adult worker ants are all female, wingless, and around 5mm in length.
Queens are significantly longer and fatter.
Larvae are white legless grubs roughly 5mm long.
Each colony can vary in size from as small as 500 individuals to many thousands.
After over-wintering, females emerge in spring and lay eggs.
The first brood will be fed by the queen for three to four weeks before pupating in the soil.
Adult workers emerge after two weeks to maintain the nest and feed the queen and subsequent larvae.
When adults find a food source they leave a trail of chemicals known as pheromones back to the nest for others to follow.
Towards the end of summer winged males and females are produced.
Between August and September mating takes place during flight.
After mating, male adults die and females shed their wings and return to the soil to overwinter.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Garden ants
Pyrethrins
Pyrethroids
There are a large number of pesticides available for ant control although these are mainly for indoor use.
Organic
Observe foraging ants and follow them back to the nest.
Dig up nests where possible making sure to remove the queen.
Encourage insectivorous birds by hanging bird boxes and feeders.
Place tin cans over the ant hill in the morning. As it heats up, the ants take their eggs up into the can. In the afternoon slide a piece of cardboard under each can, and remove and dispose of the eggs. They make a tasty treat for birds, especially chickens.
Prevention
Clean previously infested surfaces to remove pheromone trails.
Use natural predators and parasites to control aphid populations.
Dig up soil in the winter months to disturb overwintering females.
Maintain pest-free plants.
Clean honeydew from any infested plants with water.
Small piles of earth around holes in soil, lawns, paths, and at the base of exterior walls. Adults may be in the house around fresh and stored food, and on sap-sucking pest-infested plants. Large swarms of flying ants appear in late summer.
Plants affected
Garden ants rarely cause damage to plants. However, they feed on sugary foods, oily seeds, honeydew from aphid-infected plants, and other small insects. Heaps of earth around the nest entrance can be a nuisance in the lawn where they interfere with mowing, and they can also partly bury low-growing plants.
About Garden ants
There are two main species of garden ants, the red ant Myrmica rubra and the black ant, Lasius niger.
Queen ants fly in from neighbouring gardens all the time but are killed by ants from existing nests. Killing a queen and her nest simply makes space for another. For this reason it is best to focus on controlling only those nests that are causing real problems.
Adult worker ants are all female, wingless, and around 5mm in length.
Queens are significantly longer and fatter.
Larvae are white legless grubs roughly 5mm long.
Each colony can vary in size from as small as 500 individuals to many thousands.
After over-wintering, females emerge in spring and lay eggs.
The first brood will be fed by the queen for three to four weeks before pupating in the soil.
Adult workers emerge after two weeks to maintain the nest and feed the queen and subsequent larvae.
When adults find a food source they leave a trail of chemicals known as pheromones back to the nest for others to follow.
Towards the end of summer winged males and females are produced.
Between August and September mating takes place during flight.
After mating, male adults die and females shed their wings and return to the soil to overwinter.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Garden ants
Pyrethrins
Pyrethroids
There are a large number of pesticides available for ant control although these are mainly for indoor use.
Organic
Observe foraging ants and follow them back to the nest.
Dig up nests where possible making sure to remove the queen.
Encourage insectivorous birds by hanging bird boxes and feeders.
Place tin cans over the ant hill in the morning. As it heats up, the ants take their eggs up into the can. In the afternoon slide a piece of cardboard under each can, and remove and dispose of the eggs. They make a tasty treat for birds, especially chickens.
Prevention
Clean previously infested surfaces to remove pheromone trails.
Use natural predators and parasites to control aphid populations.
Dig up soil in the winter months to disturb overwintering females.
Maintain pest-free plants.
Clean honeydew from any infested plants with water.
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文章
Dummer. ゛☀
2017年09月15日
Whiteflies are harmful to both outdoor and indoor plants by sucking plant sap. Under certain conditions, they can also transmit disease. The whitefly parasite (Encarsia formosa) lays its eggs — as many as 50 to 100 — in both pupae and later larval stages of the white fly, destroying them before they can become adults. The host larva turns black as the parasite develops. It emerges, depending on conditions, in about two weeks. The adults will also feed on the larval juices released when they puncture the larvae.
Shop our large selection of beneficial insects, including whitefly parasites, at Planet Natural. One strip of cards — 500 parasitic wasps — treats up to 250 square feet and costs $29.50 with USPS Priority Mail shipping included!
Attracted to the flies by the smell of the honeydew they produce, E. formosa is an efficient biological control of whitefly and one of the most cost effective ways to control greenhouse and indoor infestations of the pest.
Humidity and strong light encourage the parasite’s activity. Temperature is also key as the parasite will not fly and seek out new prey at temperatures under 62 degrees. Its preference for warm, humid, well-lit conditions make the whitefly parasite the perfect solution for indoor and greenhouse whitefly problems.
Depending on pest levels, the following release rates have been established:
2-4 per square foot of infested area
1-2 per plant when pests are first noticed
Whitefly parasites are shipped as mature pupae in host eggs, glued to a paper card and almost ready to hatch as adult parasitic wasps. If pest levels are high, use a least-toxic, short-lived natural pesticide (insecticidal soap, botanical insecticide) to establish control, then release beneficials 2-3 weeks later to maintain control.
Shop our large selection of beneficial insects, including whitefly parasites, at Planet Natural. One strip of cards — 500 parasitic wasps — treats up to 250 square feet and costs $29.50 with USPS Priority Mail shipping included!
Attracted to the flies by the smell of the honeydew they produce, E. formosa is an efficient biological control of whitefly and one of the most cost effective ways to control greenhouse and indoor infestations of the pest.
Humidity and strong light encourage the parasite’s activity. Temperature is also key as the parasite will not fly and seek out new prey at temperatures under 62 degrees. Its preference for warm, humid, well-lit conditions make the whitefly parasite the perfect solution for indoor and greenhouse whitefly problems.
Depending on pest levels, the following release rates have been established:
2-4 per square foot of infested area
1-2 per plant when pests are first noticed
Whitefly parasites are shipped as mature pupae in host eggs, glued to a paper card and almost ready to hatch as adult parasitic wasps. If pest levels are high, use a least-toxic, short-lived natural pesticide (insecticidal soap, botanical insecticide) to establish control, then release beneficials 2-3 weeks later to maintain control.
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文章
Dummer. ゛☀
2017年09月15日
Thrips are tiny pests capable of doing sizeable damage to plants. The thrips predator (Amblyseius cucumeris) moves quickly to attack eggs, larvae and small adult thrips. Female thrips predators, while consuming two to three thrips a day, also lay two to three eggs a day, multiplying the beneficial insect’s population as it feeds.
Shop our large selection of biological controls, including thrips predators, at Planet Natural. One bottle — 50,000 predatory mites — treats up to 2,000 square feet and costs $84.95 with UPS Express shipping included!
A. cucumeris, like thrips themselves, are small (1/16 inch or less). These tan colored predatory mites are hard to spot. They are best introduced ahead of infestations or when thrips are first noticed, allowing the predator time to establish an effective population before their prey has a chance to gain footing. Once thrips populations are eliminated, this effective biological control will stay established in gardens and greenhouse, feeding on pollen and spider mites.
The delicate predator eggs are deposited on fine hairs found on the underside of the leaves. Tiny nymphs hatch within two to three days and begin feeding on pollen, pest eggs and the smallest thrips. Their entire life cycle is no more than three to four weeks. Adults are a pinkish beige, tear-drop shaped with short front legs. They’re often found resting in hiding places including leaf-stem junctures along leaf veins and in flower heads.
HOW TO RELEASE:
Gently turn and shake the bottle to mix the contents.
Spread the material evenly over leaves and throughout crops.
When introduced on rockwool, place in small heaps (2.5 ml/ plant) to encourage reproduction.
Shop our large selection of biological controls, including thrips predators, at Planet Natural. One bottle — 50,000 predatory mites — treats up to 2,000 square feet and costs $84.95 with UPS Express shipping included!
A. cucumeris, like thrips themselves, are small (1/16 inch or less). These tan colored predatory mites are hard to spot. They are best introduced ahead of infestations or when thrips are first noticed, allowing the predator time to establish an effective population before their prey has a chance to gain footing. Once thrips populations are eliminated, this effective biological control will stay established in gardens and greenhouse, feeding on pollen and spider mites.
The delicate predator eggs are deposited on fine hairs found on the underside of the leaves. Tiny nymphs hatch within two to three days and begin feeding on pollen, pest eggs and the smallest thrips. Their entire life cycle is no more than three to four weeks. Adults are a pinkish beige, tear-drop shaped with short front legs. They’re often found resting in hiding places including leaf-stem junctures along leaf veins and in flower heads.
HOW TO RELEASE:
Gently turn and shake the bottle to mix the contents.
Spread the material evenly over leaves and throughout crops.
When introduced on rockwool, place in small heaps (2.5 ml/ plant) to encourage reproduction.
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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.
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0
文章
Dummer. ゛☀
2017年09月15日
Found in warmer growing climates, mealybugs are soft-bodied, wingless insects that often appear as white cottony masses on the leaves, stems and fruit of plants. They feed by inserting long sucking mouthparts, called stylets, into plants and drawing sap out of the tissue. Damage is not often significant at low pest levels. However, at higher numbers they can cause leaf yellowing and curling as the plant weakens. Feeding is usually accompanied by honeydew, which makes the plant sticky and encourages the growth of sooty moulds. Mealybugs are a common greenhouse pest that affect ornamentals, houseplants, avocados and fruits.
Adults (1/10 — 1/4 inch long) are soft, oval distinctly segmented insects that are usually covered with a white or gray mealy wax. Small nymphs, called crawlers, are light yellow and free of wax. They are active early on, but move little once a suitable feeding site is found.
Note: There are approximately 275 species of mealybugs known to occur throughout the United States.
Life Cycle
Adult females deposit 300-600 eggs within an excreted, compact, waxy cottony-appearing mass mostly found on the underside of leaves (these egg cases can be confused with downy mildew). Egg laying is continues for about 2 weeks with the female dying shortly after all eggs are laid. Hatching occurs within 1-3 weeks and the small active yellow nymphs begin migrating over the plant in search of feeding sites on which to settle. As they feed, they secrete honeydew and a waxy coating begins to form over their bodies. Female nymphs pass through three stages (instars) with a generation taking as little as one month, depending on temperature. Male nymphs pass through five instars. They do not feed after the first two instars and exist solely to fertilize the females. In the greenhouse, continuous and overlapping generations occur throughout the year. There is little winter survival outside of greenhouses in the North.
Mealybug Control
Prune out light infestations or dab insects with a Q-tip dipped in rubbing alcohol.
Do not over water or overfertilize — mealybugs are attracted to plants with high nitrogen levels and soft growth.
Commercially available beneficial insects, such as ladybugs, lacewing and the Mealybug Destroyer (Cryptolaemus montrouzieri), are important natural predators of this pest.
Use the Bug Blaster to hose off plants with a strong stream of water and reduce pest numbers. Washing foliage regularly with a leaf shine — made from neem oil — will help discourage future infestations.
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.
Neem oil disrupts the 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. Mix 1 oz/ gallon of water and spray every 7-14 days, as needed.
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.
Washing foliage regularly with a leaf shine will help discourage future infestations.
Adults (1/10 — 1/4 inch long) are soft, oval distinctly segmented insects that are usually covered with a white or gray mealy wax. Small nymphs, called crawlers, are light yellow and free of wax. They are active early on, but move little once a suitable feeding site is found.
Note: There are approximately 275 species of mealybugs known to occur throughout the United States.
Life Cycle
Adult females deposit 300-600 eggs within an excreted, compact, waxy cottony-appearing mass mostly found on the underside of leaves (these egg cases can be confused with downy mildew). Egg laying is continues for about 2 weeks with the female dying shortly after all eggs are laid. Hatching occurs within 1-3 weeks and the small active yellow nymphs begin migrating over the plant in search of feeding sites on which to settle. As they feed, they secrete honeydew and a waxy coating begins to form over their bodies. Female nymphs pass through three stages (instars) with a generation taking as little as one month, depending on temperature. Male nymphs pass through five instars. They do not feed after the first two instars and exist solely to fertilize the females. In the greenhouse, continuous and overlapping generations occur throughout the year. There is little winter survival outside of greenhouses in the North.
Mealybug Control
Prune out light infestations or dab insects with a Q-tip dipped in rubbing alcohol.
Do not over water or overfertilize — mealybugs are attracted to plants with high nitrogen levels and soft growth.
Commercially available beneficial insects, such as ladybugs, lacewing and the Mealybug Destroyer (Cryptolaemus montrouzieri), are important natural predators of this pest.
Use the Bug Blaster to hose off plants with a strong stream of water and reduce pest numbers. Washing foliage regularly with a leaf shine — made from neem oil — will help discourage future infestations.
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.
Neem oil disrupts the 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. Mix 1 oz/ gallon of water and spray every 7-14 days, as needed.
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.
Washing foliage regularly with a leaf shine will help discourage future infestations.
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