首页
动态
文章
百科
花园
设置
简体中文
已关注
+
关注
动态 (3585)
Dummer. ゛☀
2017年09月14日
Dummer. ゛☀
Many species of the root maggot exist in home gardens throughout North America. Particularly destructive to early season plantings, they feed underground on succulent roots and attack a large variety of vegetable crops including radish, cabbage, carrot, turnip and onions. Heavily infested roots are often riddles with tunnels and rotted. Affected plants lack vigor, may be stunted or yellowed and often wilt during the heat of the day. In some cases, maggots may even chew through taproots, causing plants to die.
Adults (1/5 inch long) are dark gray flies that look like the common housefly, only smaller. They lay their eggs in the soil at the base of host plants and are very good at detecting newly planted seed beds. Maggots (1/3 – 1/4 inch long) are small, yellowish white, legless larvae with tapered or pointed heads and a rear end that is blunt. Note: Tunneling and feeding by this pest creates entry points for rot diseases such as black rot.
Life Cycle Adults emerge in the spring or early summer from overwintering pupal cocoons in the soil. They soon mate and females begin depositing 50-200 small, white eggs in plant stems right at the soil line or in cracks in the soil near plant stems. Eggs hatch in a few days and the larvae burrow down into the soil to feed on small roots, root hairs, and germinating seeds. After feeding for 1-3 weeks, maggots begin to pupate in plant roots or the surrounding soil. There are several generations per year.
Root Maggot Control Female flies are attracted for egg laying by the moisture emitted from newly planted seed rows. Cover seedbeds with floating row cover immediately after seeds are sown to prevent problems. Be sure the cover extends at least 6 inches on each side of the seed rows. Apply small amounts of Diatomaceous Earth around seedling stems to deter egg laying by adults.
Yellow Sticky Traps placed around vegetable crops will capture many adult flies before they can mate and lay eggs. Heavy paper collars or other sturdy material may be placed around the base of transplants to prevent egg laying around stems. Applying beneficial nematodes in seed furrows or as a top dressing around plants can be effective in getting rid of the larvae. Using a pyrethrin drench is also an effective option, but should only be considered as a last resort. Roto-till under crop debris immediately after harvest to destroy overwintering sites.
0
0
文章
Dummer. ゛☀
2017年09月14日
Dummer. ゛☀
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.
0
0
文章
Dummer. ゛☀
2017年09月14日
Dummer. ゛☀
Colorado potato beetles (Leptinotarsa decemlineata) are such a common pest in home gardens that they are often just called “potato bugs.” Both the adult and larval forms chew leaves and can completely defoliate an entire crop if potato beetle control methods are not implemented. Their feeding can greatly reduce yield and in some cases, may even kill plants. Alternate host plants include tomatoes, peppers and eggplant.
Adults (1/3 inch long) are rounded, yellowish-orange beetles with black stripes on their wings and black spots just behind the head. The plump larvae (1/8 to 1/2 inch long) are red with black head and legs, and become yellowish-red or orange with two rows of black spots on each side of the body. Life Cycle Overwintering beetles hibernate in the soil or garden debris, emerging in the spring. At this point, they do not have enough energy to fly and must walk in search of suitable host plants. Females lay orange-yellow eggs in clusters on the undersides of leaves. In 4-15 days (depending on temperature) hatching occurs, and the voracious larvae begin feeding on foliage for up to one month. When mature, they drop from the plant, enter the soil and pupate, emerging as adults 5-10 days later. There are 1 to 3 generations each year.
Potato Beetle Control Plant resistant cultivars when possible. In early morning, shake adults beetles from plants onto ground cloth and dump captured pests into soapy water. To impede the movement of overwintering adults, mulch at least 2-3 inches deep with a layer of clean straw or hay as soon as plants emerge. Protect plants with Harvest-Guard row cover through spring. Beneficial insects, such as ladybugs, spined soldier bugs and lacewing, feed on eggs and the young larval stages. Beneficial nematodes will attack the immature stages developing in the soil.
Diatomaceous earth contains no toxic poisons and works on contact. Dust lightly and evenly over vegetable crops wherever pest insects are found. Surround WP (kaolin clay) forms a protective barrier film, which acts as a broad spectrum crop protectant for preventing damage from chewing pests. Monterey Garden Insect Spray (Spinosad) is a highly effective bio-pesticide recommended for use against potato beetles. For best results, apply when young.
Azatrol EC 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 insect resistance to develop. Best of all, it’s non-toxic to honey bees and many other beneficial insects. Spot treat with fast-acting organic pesticides if pest levels become intolerable. After harvest pick up garden debris and turn the soil over around plants to disturb overwintering beetles.
0
0
文章
Dummer. ゛☀
2017年09月14日
Dummer. ゛☀
The Mexican bean beetle (Epilachna varivestis) is one of the most destructive insect pests of beans in the eastern United States and portions of the southwest. Both the adult and the larval stages feed on the undersides of the leaves, and sometimes will attack young pods and stems. As a result of feeding, only the veins are left, giving the leaves a lacy appearance. Damage is most severe in July and August and occurs on all bean varieties, including bush, pole, lima, pinto, navy, kidney, soybeans and cowpeas. Bush varieties seem to be attacked more readily than pole varieties.
Adult beetles (1/4 inch long) are similar in appearance to large ladybugs. They are yellow to coppery-brown in color, oval in shape, and have 16 black spots on their wing covers. Larvae (1/3 inch long) are fat, hump-backed grubs with fuzz or spines, arranged in six longitudinal rows on their backs. They are orange to yellow in color and attach themselves to leaf surfaces.
Life Cycle Adults overwinter in plant debris and other protected areas and emerge when the weather warms up in mid-to-late spring (usually when beans begin sprouting). After feeding for 1 to 2 weeks females begin to deposit yellow eggs in groups of 40 to 60 on the undersides of bean leaves. Larvae hatch in 5 to 14 days and feed for 2 to 5 weeks before pupating on the undersurfaces of leaves. Adults emerge 3 to 10 days later and live from 4 to 6 weeks. The period from egg to adult is about 30-70 days, depending on temperature. There are several generations each growing season. Mexican Bean Beetle Control Since damage is most severe during summer months, consider planting early maturing bean varieties to reduce pest problems. Hand pick the adults and immature stages from plants and drop them in a pail of soapy water. Also, remove the bright yellow eggs laid in clusters on the undersides of leaves.
Harvest-Guard can be used as a physical barrier to keep beetles and grubs from damaging plants. Beneficial insects, such as ladybugs, green lacewing and minute pirate bugs, are all voracious predators of both the egg and young larval stage. Diatomaceous earth contains no toxic poisons and works quickly on contact. Dust lightly and evenly over vegetable crops wherever pest insects are found. Surround WP (kaolin clay) forms a protective barrier film, which acts as a broad spectrum crop protectant for preventing damage from chewing pests. Spot treat with Safer Soap or other insecticidal soap and neem combinations. Thorough coverage of both upper and lower leaves is necessary for effectiveness.
Azatrol EC 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 insect resistance to develop. Best of all, it’s non-toxic to honey bees and many other beneficial insects. If pest levels become intolerable, spot treat with fast-acting botanical insecticides as a last resort. Treatments should be repeated in 7-10 days if additional beetles are found.
0
0
文章
Dummer. ゛☀
2017年09月14日
Dummer. ゛☀
Found in greenhouses, home gardens and landscaped areas across the country, leafminers are the larval (maggot) stage of an insect family that feeds between the upper and lower surfaces of leaves. On heavily infested plants it is not uncommon to find 6 or more maggots per leaf. Although damage can restrict plant growth, resulting in reduced yields and loss of vigor, healthy plants can tolerate considerable injury. Host plants include beans, blackberries, cabbage, lettuce, peppers, and a variety of ornamental flowers, trees and shrubs.
Adults (1/10 inch long) are often black to gray flies with yellow stripes and clear wings. They are similar in appearance to small, hunched-back house flies and lay their eggs on the undersides of leaves. Larvae are worm-like maggots (1/3 inch) which are often pale yellow or green in color. They create winding tunnels that are clear, except for the trail of black fecal material (frass) left behind as they feed. Note: In some cases, pathogenic fungi and bacteria may enter old mines left from eradicated insects. This can cause leaves to turn yellow and drop.
Life Cycle Mature larvae overwinter in the soil under host plants. As temperatures warm in the spring larvae pass to the pupal stage and appear as young adults in late April. Mated females use their needle-like ovipositor to lay up to 250 eggs just under the surface of the leaf epidermis. Deposited eggs may appear as small raised spots on the leaf. Within 10 days hatching larvae tunnel through the mid-leaf tissue, feeding as they go and leaving tell-tale wavy lines that are visible on the surface. Larvae mature in 2-3 weeks, and when ready to pupate, leave the leaf and drop to the soil. Once on the ground, they dig 1-2 inches into the soil and pupate. Adults emerge within 15 days as adult flies. There are several generations per year.
Damage Various types of leafminers attack various kinds of plants. They’re found on broadleaf trees, including elm, aspen, hawthorn, and poplar as well as shrubs and bushes, including lilacs. Damage can be limited in initial stages of infestations but increase as leafminer numbers multiply, and even minor infestations, while not killing a plant, will cripple its hardiness. Leafminers are a major cause of poor harvest numbers in home gardens as they weaken individual vegetable plants. They’re especially fond of spinach leaves and their tunneling severely decreases the attractiveness and value of the crop.
Leafminer Control Natural, and organic control methods work best when fighting leafminer problems. That’s because they don’t harm the naturally occurring beneficial insect populations that largely keep the leafminer and other harmful pests under control. While pesticide use can encourage leafminer outbreaks, natural controls and beneficial insects prevent as well as cure these pest problems. Don’t wait until you spot leafminer tunnels in your plants’ leaves, especially if you’ve had problems with them in the past. Be prepared with the products you’ll need to prevent and destroy infestations. Then stay vigilant.
Monitor plant leaves closely. At the first sign of tunneling, squeeze the leaf at the tunnel between two fingers to crush any larvae. Done soon enough, this killing larvae can allow plants to survive minor outbreaks. Pick off and destroy badly infested leaves in small gardens. The more healthy the plant, the less chance that leafminers will hurt it. Maintain plant health with organic fertilizers and proper watering to allow plants to outgrow and tolerate pest damage. Keep your soil alive by using compost and other soil amendments. Use floating row covers (Harvest-Guard) to prevent fly stage from laying eggs on leaves. The parasitic wasp Diglyphus isaea is a commercially available beneficial insect that will kill leafminer larva in the mine. The wasp is especially beneficial to indoor growers of ornamentals and vegetables.
Use yellow or blue sticky traps to catch egg laying adults. Cover soil under infested plants with plastic mulches to prevent larvae from reaching the ground and pupating. Azatrol EC contains azadirachtin, the key insecticidal ingredient found in neem oil. This concentrated 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. 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14日
Dummer. ゛☀
Many species of leafhoppers exist in home gardens throughout North America. Both adults and nymphs feed by puncturing the undersides of leaves and sucking out plant juices. Their toxic saliva causes spotting (white specks), yellowing, leaf curling, stunting and distortion of plants. They are also responsible for transmitting the organisms causing virus diseases in plants. Common host plants include beans, lettuce, beets, potato, grapes, roses and many others.
Leafhopper adults (1/4 inch long) are slender, wedge-shaped insects that fly or disperse rapidly when disturbed. Depending on species they may be green, brown or yellow in color and often have colorful markings. Nymphs do not have wings and are generally lighter in color than adults. Both adults and nymphs run sideways and are good jumpers.
Note: There are more leafhopper species worldwide than all species of birds, mammals, reptiles and amphibians combined. Life Cycle Adults overwinter in crop debris or non-cultivated areas adjacent to gardens. In late spring females deposit 1-6 eggs daily within the stems and larger veins of the leaves. Hatching occurs in 6-9 days, and the young nymphs molt 5 times before they become fully grown adults. White cast skins shed by the molting nymphs can often be found attached to the underside of damaged leaves. The period from egg to adult is about three weeks. Several overlapping generations may be completed during the growing season.
Leafhopper Control Remove garden trash and other debris shortly after harvest to reduce over-wintering sites. Floating row covers can be used as a physical barrier to keep leafhoppers from damaging plants.
Commercially available beneficial insects, such as ladybugs, lacewing and minute pirate bugs, are all voracious predators of both the egg and young larval stage. Apply diatomaceous earth to plants and/or spot treat with insecticidal soap to keep pest populations under control. Thorough coverage of both upper and lower infested leaves is necessary for effective control. If pest levels become intolerable, spot treat with potent, fast-acting organic insecticides as a last resort.
0
0
文章
Dummer. ゛☀
2017年09月14日
Dummer. ゛☀
Grasshoppers are voracious feeders, consuming approximately one-half of their body weight per day. Both adults and nymphs cause damage by chewing on the leaves and stems of plants, and if infestations are severe, may defoliate entire fields. It is estimated that grasshoppers consume up to 25 percent of the available forage in the western United States annually.
Adults (1-2 inch long) are brown to reddish yellow or green in color with prominent jaws, fully developed wings and short antennae. They have enlarged hind legs and can jump great distances. Immature stages — nymphs — are similar in appearance to adults, but are smaller and have wing buds instead of wings. Note: Ten adults per square yard are economically damaging to rangeland, according to the USDA. Smaller numbers can damage cropland or gardens, depending on crop type and age. A classic study showed that 6-7 adults per square yard on 10 acres of pasture ate as much as a cow.
Life Cycle The injurious species of grasshoppers are all alike in their cycle of development. Eggs are deposited in late summer in elongated masses or pods inserted in the soil. These pass through the winter, and on hatching in the spring, the young seek food in the immediate area. As they increase in size and food becomes scarce, migration to other food sources takes place. After molting 5 or 6 times, during a period of 40-60 days, the adults appear and continue feeding until cold weather kills them. One generation per year in most areas.
Control Roto-till or cultivate crops in the spring to destroy overwintering eggs. Harvest-Guard row covers can be used to cover and protect small garden areas. For long-term grasshopper protection, apply organic Semaspore Bait (Nosema locustae) to hatching beds – field margins and other undisturbed grassy areas – when grasshoppers are young. Heavy infestations may require multiple applications. 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.
Spread EcoBran Bait or apply botanical insecticides, such as organic pyrethrins, to areas where you are experiencing heavy grasshopper damage and require a quick-kill. Read our pamphlet on How to Control Grasshoppers with Modern Baits here. Tip: Mow a “clean” strip between grassy fields and your garden area to help slow grasshopper migration. Pests are reluctant to enter the strip because it has no food, and they are very exposed to predators. A wider strip is better, especially if the adjacent area is large.
0
0
文章
Dummer. ゛☀
2017年09月14日
Dummer. ゛☀
In the mid 1800s, gypsy moth larvae (Lymantria dispar) that were being evaluated for silk production were blown from a window sill in Medford, Massachusetts. The first outbreak of gypsy moth occurred in 1889. By 1987, the gypsy moth had established itself throughout the Northeast and is now found throughout much of the Eastern United States. It is one of the most damaging pests of hardwood forests and urban landscapes, defoliating a million or more forested acres annually. Gypsy moths are spread over large areas primarily by shipment of infested nursery stock or any object on which eggs may be deposited.
Only the caterpillar stage of the gypsy moth feeds. When fully grown, they will be approximately 2 inches long, very hairy and have five pairs of blue dots followed by six pairs of red dots along its back. Adults are gray (male) or white (female) colored hairy moths with a 1-1/2 – 2 inch wingspan. Although both sexes are winged, the female moth does not fly.
Life Cycle The female gypsy moth lays an egg mass, covering it with body hairs to act as insulation and to help protect the eggs from predators. Shortly after the female gypsy moth lays the egg mass, she dies, and the eggs wait out the winter until temperatures rise in the spring and a hatch begins. Upon hatching, small black headed gypsy moth caterpillars, climb to the tops of the trees where they may begin to feed on foliage or they may dangle from silk strands and drift in the wind to colonize other trees. Gypsy moth caterpillars go through five or six instars and feed from late April to mid June. Most of the feeding occurs at night to protect caterpillars from extreme heat and predation by birds during the day. When fully mature, caterpillars stop feeding, and change into pupae. Adult moths emerge 7-10 days later. There is one generation per year.
Gypsy Moth Control Keep your yard as clean as possible. Remove discarded items, dead branches, stumps, etc., where the adult female moth is likely to lay egg masses. Destroy any egg masses that are found. The Gypsy Moth Trap is used to monitor the moth population and may also prevent male moths from homing in on females. Tanglefoot Pest Barrier or Sticky Tree Bands can be placed around tree trunks to help curtail the caterpillars movement into and out of the tree canopy. Apply Bacillus thuringiensis, var. kurstaki or Monterey Garden Insect Spray (Spinosad) to the leaves of trees to kill gypsy moth caterpillars. For best results, sprays must be applied when caterpillars are young, less than one inch long. In instances where populations are high, two (or more!) applications five days apart might be needed.
Azatrol EC contains azadirachtin, the key insecticidal ingredient found in neem oil. This concentrated 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. 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14日
Dummer. ゛☀
Many species of flea beetles are found throughout the United States. They are small jumping insects (similar in appearance to fleas) commonly found in home gardens early in the growing season. A voracious pest, they will damage plants by chewing numerous small holes in the leaves, which make them look as if they have been peppered by fine buckshot. When populations are high, flea beetles can quickly defoliate and kill entire plants. They feed most on hot sunny days and attack a wide variety of plants including beans, cabbage, corn, eggplant, potatoes, peppers, tomatoes, lettuce and most seedlings. Adults are small (1/10 inch long), shiny, dark brown or black beetles with large hind legs that allow them to jump when disturbed. Some species may have white or yellow stripes on their wing cases. Larvae are small, cream-colored worms (1/8 – 1/3 inch long). They live underground and feed on the roots and tubers of young plants as well as on germinating seeds.
Note: Flea beetles transmit viral and bacterial diseases. Life Cycle Adults overwinter in the soil or garden debris and become active in the spring, feeding on host plants as new growth appears. Tiny white eggs are laid on or in soil cracks around the base of plants. These hatch in about one week, and the slender white larvae feed on plant roots for approximately 2-3 weeks. Pupae usually remain in the soil for 7-9 days until adults emerge and the cycle is completed. There are one to four generations per year, depending on species and climate.
Flea Beetle Control Remove garden trash and plow or roto-till under weeds to reduce overwintering sites. Floating row covers are extremely effective when placed on seedlings and left in place until plants are old enough to tolerate beetle damage. Place yellow sticky traps throughout garden rows every 15 to 30 feet to capture adults. Beneficial nematodes applied to the soil will destroy the larval stage, reducing root feeding and helping to prevent the next generation of adults from emerging.
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! Surround WP (kaolin clay) forms a protective barrier film, which acts as a broad spectrum crop protectant for preventing damage from insect pests. Azatrol EC contains azadirachtin, the key insecticidal ingredient found in neem oil. This concentrated product is approved for organic use and 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.
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
相关用户
举报 反馈

您有什么意见或建议,欢迎给我们留言。

请输入内容
设置
VIP
退出登录
分享

分享好文,绿手指(GFinger)养花助手见证你的成长。

请前往电脑端操作

请前往电脑端操作

转发
插入话题
提醒好友
发布
/
提交成功 提交失败 最大图片质量 成功 警告 啊哦! 出了点小问题 转发成功 举报 转发 显示更多 _zh 文章 求助 动态 刚刚 回复 邀你一起尬聊! 表情 添加图片 评论 仅支持 .JPG .JPEG .PNG .GIF 图片尺寸不得小于300*300px 最少上传一张图片 请输入内容