文章
Dummer. ゛☀
2017年09月15日
Colonies can usually be found on the undersides of leaves as well as on soft new shoot tips or buds. Black bean aphids cluster together and are noticeable because of their dark colouring. As they feed, they secrete a sticky, honeydew substance which drips onto lower foliage and often becomes covered in a sticky black mould.
Plants affected
Black bean aphids affect a wide range of garden plants, trees shrubs and certain vegetables (mainly beans and peas).
About Black bean aphid
The black bean aphid is more commonly known as 'Black fly'.
Adult aphids are up to 2mm long and elliptical in shape. They are black in colour, although they can also appear dark green or purple.
Black bean aphid infestations are commonly managed by black garden ants which 'farm' the aphids and 'milk' the sticky honeydew that they produce. Ants will often carry young aphids onto new plants to establish new colonies.
Large colonies can cover areas on the youngest sections of stems, and the undersides of leaves and sometimes on flowerbuds.
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 overwinter.
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. However, this is less common with black bean aphids where ants are collecting the honeydew.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Black bean aphid
Pyrethrum
Natural fatty acids
Surfactant based products
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Inspect plants regularly and deal with early symptoms immediately.
Remove as many aphids as you can by hand or, if possible, cut off infested shoots and stems on susceptible shrubs.
Spray the infested areas of a plant with a strong jet of water to keep aphid numbers down.
Use nettings and fleeces to stop aphids spreading to susceptible plants.
Encourage natural aphid predators such as ladybirds, Aphidoletes, hoverfly and lacewing larvae. These can be obtained from commercial suppliers and released on to affected plants outdoors.
For greenhouse plants use parasitic wasps of aphids such as Aphidius matricariae and Aphidius ervi which can be purchased for release in a contained space.
Prevention
Regularly check plants for signs of aphid infestation and deal with them as soon as they appear.
Encourage natural enemies.
Avoid using broad spectrum insecticides which will kill beneficial insects as well as aphids.
Encourage insectivorous birds by hanging feeders during the winter months and provide nesting boxes in the spring.
Plants affected
Black bean aphids affect a wide range of garden plants, trees shrubs and certain vegetables (mainly beans and peas).
About Black bean aphid
The black bean aphid is more commonly known as 'Black fly'.
Adult aphids are up to 2mm long and elliptical in shape. They are black in colour, although they can also appear dark green or purple.
Black bean aphid infestations are commonly managed by black garden ants which 'farm' the aphids and 'milk' the sticky honeydew that they produce. Ants will often carry young aphids onto new plants to establish new colonies.
Large colonies can cover areas on the youngest sections of stems, and the undersides of leaves and sometimes on flowerbuds.
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 overwinter.
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. However, this is less common with black bean aphids where ants are collecting the honeydew.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Black bean aphid
Pyrethrum
Natural fatty acids
Surfactant based products
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Inspect plants regularly and deal with early symptoms immediately.
Remove as many aphids as you can by hand or, if possible, cut off infested shoots and stems on susceptible shrubs.
Spray the infested areas of a plant with a strong jet of water to keep aphid numbers down.
Use nettings and fleeces to stop aphids spreading to susceptible plants.
Encourage natural aphid predators such as ladybirds, Aphidoletes, hoverfly and lacewing larvae. These can be obtained from commercial suppliers and released on to affected plants outdoors.
For greenhouse plants use parasitic wasps of aphids such as Aphidius matricariae and Aphidius ervi which can be purchased for release in a contained space.
Prevention
Regularly check plants for signs of aphid infestation and deal with them as soon as they appear.
Encourage natural enemies.
Avoid using broad spectrum insecticides which will kill beneficial insects as well as aphids.
Encourage insectivorous birds by hanging feeders during the winter months and provide nesting boxes in the spring.
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文章
Dummer. ゛☀
2017年09月15日
Leaves will become a dark brown colour and drop. Blossoms will die back. Fruits will become discoloured and wrinkled. A white slimy substance may excrete from infected areas. Often, the first time this disease becomes apparent is when new leaves do not appear in spring on deciduous trees and shrubs. Alternatively, woody plants may suddenly defoliate and die-back along their stems. Determining the cause as honey fungus can be tricky though. A clear indicator is the presence of strands of the fungus in the soil around affected plants. These look like thick black bootlaces. Pale brown or yellowish toadstools may appear in autumn and a gooey resin may be found oozing from the base of stems.
Plants affected
The most susceptible include: apples, crab apples, walnut, willow, wisteria, cotoneaster, rhododendron, roses and many conifers, including pine, cypress and thuja. In addition almost all garden trees and shrubs and some herbaceous plants can also succumb.
About Honey fungus
Honey fungus lives in dead tree stumps and spreads from there to healthy plants nearby.
There are a group of closely related fungi which are collectively known as honey fungus.
Honey fungus is notoriously difficult to diagnose as the symptoms are easily confused with other problems.
Honey fungus remains in the soil for years if allowed to establish.
Treatment
Chemical
There is currently no chemical control commercially available for honey fungus.
Organic
Remove diseased plants and dig out the roots as far as possible.
Do not replant with trees or shrubs for at least a year.
Remove and replace the infected soil from around the affected plant.
Where possible, have any large stumps removed from the garden.
When replanting, stick to resistant plants such as oak, ash, beech, yew, clematis, laurel or mahonia.
Prevention
Sterilise any tools used for removing infected material with a household bleach solution after every use
Plants affected
The most susceptible include: apples, crab apples, walnut, willow, wisteria, cotoneaster, rhododendron, roses and many conifers, including pine, cypress and thuja. In addition almost all garden trees and shrubs and some herbaceous plants can also succumb.
About Honey fungus
Honey fungus lives in dead tree stumps and spreads from there to healthy plants nearby.
There are a group of closely related fungi which are collectively known as honey fungus.
Honey fungus is notoriously difficult to diagnose as the symptoms are easily confused with other problems.
Honey fungus remains in the soil for years if allowed to establish.
Treatment
Chemical
There is currently no chemical control commercially available for honey fungus.
Organic
Remove diseased plants and dig out the roots as far as possible.
Do not replant with trees or shrubs for at least a year.
Remove and replace the infected soil from around the affected plant.
Where possible, have any large stumps removed from the garden.
When replanting, stick to resistant plants such as oak, ash, beech, yew, clematis, laurel or mahonia.
Prevention
Sterilise any tools used for removing infected material with a household bleach solution after every use
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文章
Dummer. ゛☀
2017年09月15日
Cankers are deformed and diseased areas of tree bark. The directly infected area is usually sunken down, with the surrounding bark cracked and distorted. Initial signs of infection may include new shoots dying and wilting or discoloured leaves. Fruits can also be affected and may rot. Cankers usually have white or red coloured pustules depending on the time of year.
Plants affected
Apple canker infects apple, pear, mountain ash, beech, hawthorn, poplar and willow. Some varieties are more susceptible than others.
About Apple canker
Apple cankers occur when the fungus Nectria galligena finds its way into cracks and wounds in tree bark.
The infection will kill the tissue beneath the bark first.
The bark around the canker will eventually die back revealing the tissue.
Damage from pruning can also become infected.
Fungal spores appear creamy white in the spring and a darker red colour later in the year.
Spores can move between wounds by wind, water splash, or insect.
Wet soil exacerbates the infection.
Mild infections still allow some fruit to set.
Severe infections can rarely be cured and the tree may die.
The more infected and exposed areas a tree has, the more susceptible it is to further damage and infections.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Apple canker
Myclobutanil
Mancozeb
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Remove infected branches and twigs, making clean, neat cuts.
Larger cankers on trunks and thick branches can be cut out, although care must be taken to ensure that all bark showing symptoms of disease is removed.
Burn all removed infected material to ensure the spores are destroyed.
Prevention
Disinfect blades before and after pruning.
After pruning, apply canker paint to exposed healthy tissue.
Try to prune only in dry weather.
When planting new trees, pick varieties with a higher level of resistance to canker.
Include a spade of lime with the soil when planting a new tree.
Pruning back leaves and branches to improve the air circulation of older trees will help to stop the disease establishing.
Plants affected
Apple canker infects apple, pear, mountain ash, beech, hawthorn, poplar and willow. Some varieties are more susceptible than others.
About Apple canker
Apple cankers occur when the fungus Nectria galligena finds its way into cracks and wounds in tree bark.
The infection will kill the tissue beneath the bark first.
The bark around the canker will eventually die back revealing the tissue.
Damage from pruning can also become infected.
Fungal spores appear creamy white in the spring and a darker red colour later in the year.
Spores can move between wounds by wind, water splash, or insect.
Wet soil exacerbates the infection.
Mild infections still allow some fruit to set.
Severe infections can rarely be cured and the tree may die.
The more infected and exposed areas a tree has, the more susceptible it is to further damage and infections.
Treatment
Chemical
Products containing the following chemical ingredients are all effective on Apple canker
Myclobutanil
Mancozeb
Note: It is important to read manufacturer's instructions for use and the associated safety data information before applying chemical treatments.
Organic
Remove infected branches and twigs, making clean, neat cuts.
Larger cankers on trunks and thick branches can be cut out, although care must be taken to ensure that all bark showing symptoms of disease is removed.
Burn all removed infected material to ensure the spores are destroyed.
Prevention
Disinfect blades before and after pruning.
After pruning, apply canker paint to exposed healthy tissue.
Try to prune only in dry weather.
When planting new trees, pick varieties with a higher level of resistance to canker.
Include a spade of lime with the soil when planting a new tree.
Pruning back leaves and branches to improve the air circulation of older trees will help to stop the disease establishing.
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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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成长记
littlebadger
2017年09月15日
I new added a "Portulacaria afra variegata (elephant bush)" in my "garden"
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文章
Dummer. ゛☀
2017年09月15日
A soil-borne fungal disease that affects seeds and new seedlings, damping off usually refers to the rotting of stem and root tissues at and below the soil surface. In most cases, infected plants will germinate and come up fine, but within a few days they become water-soaked and mushy, fall over at the base and die.
Several fungi can cause decay of seeds and seedlings including species of rhizoctonia, fusarium and phytophthora. However, species of the soil fungus pythium are most often the culprit. Damping off typically occurs when old seed is planted in cold, wet soil and is further increased by poor soil drainage. High humidity levels, rich potting soils and planting too deeply will also encourage its growth.
Fungal spores live in the soil and are primarily a problem in seed beds. They can be transported on garden tools and in garden soils taken into the house or greenhouse.
Note: Older plants are rarely killed by damping off primarily because the production of secondary stem tissue forms a protective barrier and limits fungal penetration.
Treatment
There is no cure for plants that already have damping off. However, you can easily prevent the problem by providing good air circulation. A small fan or simply cracking the lid of the germination tray will suffice. The biological fungicide Mycostop may also be used as a seed treatment to prevent seed or soil-borne diseases. Other steps for preventing damping off include the following:
When starting seeds indoors, use good organic potting soil or sterilize your own potting soil in an oven.
Make sure your seed starter mix is light and fast-draining.
Plant seedlings so that the soil surface is near the top of the container to insure proper air circulation.
Sow seeds thinly to prevent over crowding which can lead to humid, moist conditions.
Seedling trays that provide water from below are preferable to overhead watering.
Never water past noon so that the soil surface and the plants are dry by evening.
Avoid overwatering tender seedlings.
Organocide® Plant Doctor is an earth-friendly systemic fungicide that works its way through the entire plant to combat a large number of disease problems. Apply as a soil drench or foliar spray (3-4 tsp/ gallon of water) to prevent and attack many fungal problems, including pythium, fusarium and root rot.
Several fungi can cause decay of seeds and seedlings including species of rhizoctonia, fusarium and phytophthora. However, species of the soil fungus pythium are most often the culprit. Damping off typically occurs when old seed is planted in cold, wet soil and is further increased by poor soil drainage. High humidity levels, rich potting soils and planting too deeply will also encourage its growth.
Fungal spores live in the soil and are primarily a problem in seed beds. They can be transported on garden tools and in garden soils taken into the house or greenhouse.
Note: Older plants are rarely killed by damping off primarily because the production of secondary stem tissue forms a protective barrier and limits fungal penetration.
Treatment
There is no cure for plants that already have damping off. However, you can easily prevent the problem by providing good air circulation. A small fan or simply cracking the lid of the germination tray will suffice. The biological fungicide Mycostop may also be used as a seed treatment to prevent seed or soil-borne diseases. Other steps for preventing damping off include the following:
When starting seeds indoors, use good organic potting soil or sterilize your own potting soil in an oven.
Make sure your seed starter mix is light and fast-draining.
Plant seedlings so that the soil surface is near the top of the container to insure proper air circulation.
Sow seeds thinly to prevent over crowding which can lead to humid, moist conditions.
Seedling trays that provide water from below are preferable to overhead watering.
Never water past noon so that the soil surface and the plants are dry by evening.
Avoid overwatering tender seedlings.
Organocide® Plant Doctor is an earth-friendly systemic fungicide that works its way through the entire plant to combat a large number of disease problems. Apply as a soil drench or foliar spray (3-4 tsp/ gallon of water) to prevent and attack many fungal problems, including pythium, fusarium and root rot.
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