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Dummer. ゛☀
2017年09月15日
Dummer. ゛☀
The peach tree borer (Synanthedon exitiosa) does damage to a variety of stone fruit trees. It attacks not the fruit, but the tree itself, burrowing into its trunk near or beneath ground level and devouring its way into the living cambium layer underneath.
Heavy infestations, recognizable from the circle of oozing frass (the larvae’s excreted waste) around the trunk, can completely girdle trees, killing them if left untreated. Young trees are especially vulnerable. Older trees that survive attacks will show less vigor and inferior fruit quality. Borers are historically found across the United States and in parts of Canada, almost anywhere stone fruits grow. They existed on wild cherry and plum trees before non-native apricots, nectarines and peaches were introduced. Today, they’re a common and persistent threat to both commercial and home orchardists. The larvae of peachtree borers are white to beige and brown and obtain an length of an inch or more. The chewing end of the larvae darkens as it matures. Despite they’re size, they’re seldom seen as they bore beneath a tree’s bark, gouging out wide, fass-filled tunnels. Pupae, wrapped in silky cocoons, are also unseen hidden inside the tree.
Adult moths have translucent wings and resemble wasps. Females are metallic blue and marked with an orange band on their abdomen. Males are smaller and are marked with yellow stripes. Their emergence a week or two into the summer sets off a frenzy of mating and egg laying. The lesser peachtree borer (Synanthedon pictipes) is found in the eastern United States, across the southern states to Texas and the midwestern states to Minnesota. It attacks more of the tree, including primary limbs, and is more likely than Synanthedon exitiosa to produce eggs throughout the season. Larva are similar in appearance to exitiosa, but male moths have narrower, more numerous yellow bands across their abdomens. The pest’s life cycle and treatment is similar to those of exitiosa.
Life Cycle Adults begin emerging in late spring and early summer from larvae that have overwintered inside the tree an inch or two beneath the soil line. They continue to emerge throughout the summer and into the fall. Knowing when moths first emerge in your region, as early as April in Georgia and other warmer areas but more commonly in May and June, is critical to controlling the pest. The moths begin breeding almost as soon as they emerge. Females lay as many as 400 eggs on the trunk of the tree near the soil line or in the soil against the tree. The eggs take ten days to hatch.
Larvae immediately seek entrance into the tree’s bark, often through cracks, chips and other damage. They tunnel through the bark into the vulnerable cambium layer beneath it and beyond, growing as they do. Some may pass through to adult stage in a single season. As cold weather sets in, larvae will reduce activity and overwinter inside the tree. They begin feeding again when temperatures warm. In spring, the larvae migrate from their holes, pupating near the entrance to their burrow or in nearby soil, creating a gummy cocoon of silk thread and bits of wood. The cocooning and pupation stages before moths emerge takes as much as four weeks. Moths begin laying eggs within minutes of taking to the air. Utah State University Extension Cooperative (PDF) has wonderful color photographs of the pest’s various stages.
Damage Peach tree borers bring major harm to important fruit-crop trees, destroying the tree’s vascular system through boring and girdling while inducing plant pathogens to invade the weakened tree. Colorado State University’s Extension website doesn’t pull punches when addressing the pest’s effect on home and commercial growers, calling it “the most destructive insect pest of peach, cherry, plum and other stone fruits in Colorado.” The University of Florida’s Institute of Food and Agricultural Sciences provides perspective: “The peachtree borer and the lesser peachtree borer, Synanthedon pictipes, account for more damage to peach trees than all other insect pest combined.” Borer damage inhibits the conduction of water and nutrients up the trunk to the tree’s branches, leaves and fruits. One or two borers will harm its growth and fruiting. Several burrowing into the same tree, fouling their tunnels with their waste, can kill a newly infested tree in a single season.
Infestation are most common in older trees that have seen damage from canker, harsh winters, pruning and mechanical injury (like trunks being hit by mowers). This give the larvae an easy way into the tree’s insides. The lesser peachtree borer is particularly attracted to older, damaged trees. Numerous larvae cluster at these places in “galleries” where substantial damage may be done. The Missouri Botanical Garden has photos of damage signs as well as the larvae at work. Control Don’t allow borers to get established. Most trees will survive attack from small numbers. But large numbers of larvae can completely girdle a tree, killing it. Once the larvae move into the bark, they are difficult to manage. They’re most vulnerable at the surface before they chew their way into the tree’s bark and cambium layer.
Wild trees provide a year-to-year home for borers. If you have wild plum, cherry or other stone fruits in your woodlot, consider clearing them. Female adults are attracted to diseased, damaged and otherwise stressed trees. Removing and replacing older, stressed trees that harbor borers can help make control issues easier to deposit their eggs. Healthy, adequately watered trees are less likely to invite infestation. Take care to keep your trees strong and undamaged. Borer treatment begins early in spring even before larvae become active. Probe small holes in trunks near the soil line, especially those with evidence of frass, with the point of a knife or stiff wire to crush larvae (and later pupae) beneath the bark. In severe infestations, scoop soil out from around the crown of the tree where frass collects and use a sharp-pointed object to dig out the larvae, taking care not to harm the tree. Be on watch and prepared for the emergence of adult moths. Because they begin breeding and laying eggs within hours of emerging, it’s important to treat for them as soon as they appear. Ask local nurserymen when the first moths are expected in your area. Monitor trees for moth activity daily and keep journal records for future years. Use pheromone traps or Tangle-Trap® Insect Trap Coating to capture adults. Inspect traps daily.
Begin spraying organic neem oil in the highest recommended concentrations around the crown of the tree and up the first six to 12 inches of the trunk when adults are anticipated. Saturate both bark and soil. The oil will disrupt the moths’ breeding cycle and discourage them from leaving eggs. It will also neutralize eggs that may already have been laid as well as penetrate the bark and inhibit development of larvae already in the tree. Spray twice a month throughout the breeding season which can last until September. Reapply after rains. Citrus extract sprays will repel adults and discourage egg laying. Begin spraying trunks and around the crown of the tree just ahead of moth hatch. Paint tree trunks and exposed roots with a paste of Surround WP, a powder made of kaolin clay. Coat base of tree, exposed roots and trunk up to 12 inches. Once dry, the coating deters adults and their egg laying. Applications of Bt (Bacillus thuringiensis), a naturally occurring soil bacteria, will disrupt larvae and kill them depending on exposure. Spray Bt directly into borer holes after clearing out as much frass as possible.
Spinosad, an OMRI listed pesticide, can also be sprayed on tree trunks as larvae hatch and directly into borer holes. Spraying can be repeated every five or six days up to two weeks before harvest. A recent study has shown that beneficial nematodes work against this destructive scourge. Nematodes attack eggs, larvae and pupae of numerous insect pests in soil. A spring application of nematodes suppressed 88% of orchard borer infestations. Spring and fall applications were found to be 100% effective. Parasitic wasps can help with lesser peach tree borer whose eggs can be found. They are not effective on the pupae of the common, greater peachtree borer because they’re under the soil line out of the wasp’s reach. But certain wasps will parasitize eggs found on bark and just-hatched larvae that have not yet worked their way into the tree. Woodpeckers and other birds will reduce numbers by grabbing larvae on and under the bark. Encourage them by providing suitable habitat and not spraying harmful pesticides.
Cedar chips and bark spread around the base of stone fruit trees is said to repel egg-laying adult moths. In the south, spreading tobacco dust around the base of trees is a traditional method of discouraging pests. Some do-it-yourself sources advise the use of moth crystals to “gas” the larvae inside their burrows. It’s suggested that crystals worked into the soil at the trees crown will emit vapor that penetrates into the tree. Moth crystals, like moth balls, are made from napthalene, a suspected carcinogen which is also linked to liver failure and neurological damage in infants. Using and handling naphthalene — not a natural-gardening practice — should be avoided.
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Dummer. ゛☀
2017年09月15日
Dummer. ゛☀
Found in all apple-growing areas of the world, the codling moth (Cydia pomonella) is considered to be one of the most destructive pests of apples. Adults are gray to brown moths with a 3/4 inch wingspan. They have a chocolate-colored patch at the tip of each forewing and coppery transverse markings.
Codling moth larvae are pink or creamy white caterpillars with mottled brown heads that tunnel through apples directly to the core. As they feed, they push out mounds of fecal material, called frass, which gathers around the entrance hole. Damage lowers the market value of the fruit and makes it unfit for human consumption. Alternate host plants include pears, crabapples, walnuts and stone fruits. Note: The codling moth was introduced to North America by the colonists more than 200 years ago and is now one of the leading pests in home orchards.
Life Cycle Full grown larvae pass through the winter in a cocoon beneath loose bark or in orchard litter. Pupation takes place in the spring. Moths begin emerging about the time that apple trees are in bloom and lay an average of 50 to 60 eggs on leaves, twigs and fruits. Once eggs hatch the larvae feed briefly on leaves, then damage fruit by boring into the centers. Larvae feed for three weeks, then leave to seek a suitable place to spin cocoons. There are two generations per year. Control Scrape loose bark in early spring to remove overwintering cocoons and then spray All Seasons® horticultural oil to eradicate eggs and first generation early instar stages. Beneficial nematodes are microscopic, worm-like parasites that actively hunt, penetrate and destroy immature stages of this pest. Spray on trunks and main branches, and also over the soil out to the drip line for a 60% to 90% mortality in pre-pupae.
Use pheromone traps to determine the peak flight period for moths, then release trichogramma wasps to attack eggs. Pheromone traps will also help reduce male moths where populations are low and trees are isolated. Surround WP — a wettable kaolin clay — can be used to deter a broad range of fruit tree pests (and diseases), and will reduce codling moth damage by 50-60%. Apply before moths arrive and continue for 6-8 weekly applications, or until the infestation is over.
In areas of severe infestation, spray plant-derived insecticides when 75% of petals have fallen, followed by three sprays at 1-2 week intervals. These natural pesticides have fewer harmful side effects than synthetic chemicals and break down more quickly in the environment.
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Dummer. ゛☀
2017年09月15日
Dummer. ゛☀
Slightly smaller than a housefly, adult apple maggots (Rhagoletis pomonella) are 1/5 inch long and have conspicuous black bands — resembling a W — running across their transparent wings. The larvae (1/4 inch long) are white, tapered maggots that tunnel throughout the flesh of fruit. They are often found in large numbers and can quickly reduce a beautiful apple to a brown, pulpy mess. External signs of maggot infestation appear as pinpricks made on the apple surface. These are often small, distorted or pitted areas.
Life Cycle The apple maggot overwinters as pupae in the soil. Adult flies emerge in late spring and begin to lay eggs just under the apple skin. The eggs hatch, and the larvae begin to tunnel through the fruit. When mature, the maggot leaves through a small opening made in the side of the fruit and enters the soil. One or two generations per year.
Control The majority of maggots leave the fruit several days after it has fallen from the tree. As a result, a certain level of control can be achieved by picking up and discarding the dropped apples. Red Sphere Traps will greatly reduce damage and work well to capture and reduce the number of egg laying adults. Traps should be placed within the canopy just as trees are finished blooming. Hang spheres high in the brightest areas of the tree, 6-7 feet from the ground. Set out one trap for every 150 apples (2 traps per dwarf tree).
Beneficial nematodes are microscopic, worm-like parasites that actively hunt, penetrate and destroy the pupal stage of this pest. For best results, apply in the early spring or fall around the base of trees, out to the drip line. One application will continue working for 18 months. Surround WP — made from kaolin clay — will suppress a broad range of insects and has shown over 90% control of apple pests. It also has a positive effect on fungal diseases like fire blight, sooty blotch and flyspeck.
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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Dummer. ゛☀
2017年09月15日
Dummer. ゛☀
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.
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Dummer. ゛☀
2017年09月15日
Dummer. ゛☀
Hemp and russet mites are part of the eriophyid family of mites. Among the 100 or so plant-specific eriophyid species, including gall, rust, and blister mites, the tomato-attacking, microscopic russet mite is among the hardest to detect. Visible, if then, only in clusters, a single mite is too tiny to be seen by the human eye without magnification of 10x and higher. Their near invisibility makes these mites a particular threat to become established in your garden before you realize it.
Unlike spider mites, these voracious plant pests leave no webbing or other secretions when present. Visible damage to the plant is the first indication of its presence a damage often mistaken for mineral and other nutritional deficits. Seen through a lens, russet-hemp mites are tapered, translucent, wedge-shaped cylinders that take on a yellow tint, especially in groups. Unlike most varieties of mites, eriophyid, including russet mites, have only two pairs of legs. Like spider mites and others, they are increasing their range and are now common in places not previously seen. Because of their size, they’re effectively dispersed by wind.
Crop specific, they tend to multiply in areas of intensive growing, like the tomato raising regions of Florida, and also do quite well indoors where warm, moist environments facilitate rapid reproduction. In the past decade, they have spread from growers in California north into Oregon. Lifecycle Females over winter just inside stems of the plants they infest or where twigs are joined to stems. Translucent eggs, nearly adult in size, are laid in spring and go through two nymph stages, both little different than the adult. The mites produce multiple, over-lapping generations through the course of a season, maturing in as little as eight days in warm, humid conditions.
Damage Mites are sap suckers working at the cellular level. Damage typically appears first at the bottom of plants and moves upward as they feed. Lower leaves begin to yellow and curl, the leaf droops and the stem discolors. As the plant’s nourishment is sucked away, less vigorous green growth and flowering is observed. The tiny mites, in increasing numbers, spread to all parts of the plant. The mites seem particularly attracted to flower resins and will congregate in flowers and blossoms where they can effectively hide and do great damage. If left unchecked, the mites will eventually sap the entire plant. Russet Mite Control The best controls for both indoor and outdoor growers are preventive methods. Make sure you don’t introduce mites into your grow space by bringing in infected plants or contaminated potting soil that may carry female mites or eggs. Regular and close scrutiny of your plants, especially around the leaves nearest the soil line if outdoors, or anywhere a plant is flowering, is crucial to early detection. What might appear to be an iron or magnesium deficiency may well be an infestation of russet mites. If in doubt, treat for mites as well as adjusting nutrient solutions or amending soil. Finding and removing mites in their first generation, a period that can be short as a week under the right conditions, can short-circuit a cascade of generations once the mites begin laying eggs.
Many of the precautions and treatments used on spider mites also apply to this pest. Inspection of plants is crucial during treatment. Look to see if damage has stopped. Remove all damaged leaves, stems, and even entire plants and dispose in a way that won’t spread the tiny creatures or its eggs. Outdoor Plants: Russet mites are most frequently found in outdoor container plantings. This suggests that they’re introduced both in potting soils and plants brought into the garden. Use only dependable, high-quality potting medium and plants from a nursery you trust. Don’t be afraid to ask if mites have been a problem. Even if they’ve been dealt with and the plant shows no signs of damage, eggs may still exist in the soil. Introducing beneficial nematodes just as soil temperatures begin to warm and ahead of planting can help destroy eggs that are in the soil and nymphs once they hatch. Apply a second round of vermiculite-carried nematodes if damage to lowest leaves is spotted. Avoid over-fertilizing plants. Mites are attracted to vigorous green growth that comes of too much nitrogen. Periodic releases of predatory mites can blunt infestations, giving you time to deal with them. (Yes, the same spray mentioned below will also kill beneficial mites.)
Because of their near invisibility, it’s difficult to apply insecticidal soaps to suspected mite infestations. Home-made sprays using garlic, hot peppers, or citrus oils will not usually take down mites but may provide some deterrent. (Because they often arrive in the wind, russet-hemp mites aren’t easily deterred.) Neem oil will repel and kill mites. It should be applied at first signs of damage. Pyrethrum sprays have proven effective in killing mites but require complete coverage to ensure that none of the microscopic pests are overlooked. Tailor applications to the lifecycle of the mite. Spraying once a week — once every five days in warm conditions — for three to four weeks should cover adults, emerging nymphs, and eggs.
No matter which method you’re using, close inspection of plants during treatment is crucial. Use a lens of 14X magnification or larger to see mites gathered at the center of curled leaves, at stem junctures, or in flowers. Don’t wait to see how effective one treatment is before continuing or using another. Once infestations spread up plants, it’s almost impossible to save the plant. Don’t hesitate to discard entire plants, even if they’re not entirely affected. While you’re treating affected plants, the mites are hurriedly spreading to others.
Prevent spreading mites. Discard infested plants in plastic bags and dispose of them in sealed garbage containers. Indoor Plants: Do not bring uninspected plants or plants from any grower who’s had previous problems with mites into your grow space. This is especially important, whether taking clones or tomato starts from friends and professionals. Know your grower. Keep a clean grow space. Don’t introduce unnecessary tools used outside or suspect soil or growing mediums. Periodic releases of spider mite predators in a greenhouse can help keep pests at bay. At the first sign of mites, reduce their breeding environment by adjusting room temperatures and moisture content as much as possible. This will slow the breeding cycle, buying you time to inspect and treat plants before the mites next generation is spawned.
Azamax will discourage mites from feeding and slow their breeding cycle, especially helpful if you’re moving towards harvest. Neem oil and pyrethrum/ canola oil sprays, used as above, will knock down mite infestations with repeated use. If your grow space has been infected, clean it from top to bottom. Scrub benches and other equipment with a mild bleach solution (1:10 bleach-to-water solution is said to be safe for cleaning according to the Centers For Disease Control), sterilize all hydroponic equipment, throw away any soil that can’t be sanitized, and leave nothing that was in the space during the infestation unscrubbed. The invisible eggs of this troublesome pest can survive in tiny, unseen places.
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Dummer. ゛☀
2017年09月15日
Dummer. ゛☀
Root aphids — aphids that stay at or above the soil line — are from the family Phylloxera, a near-cousin of aphids. They are an escalating problem, especially among indoor growers, and spreading through parts of the country where they haven’t been seen before. They’re hard to spot and unlike small colonies of green and other aphids found on stems and leaves, root aphids are more likely to get out of control. They can multiply quickly, unseen, and sap enough vigor from your plants to kill them.
Because they’re small — about the size of a mite — and often colored to blend with roots and soil, Phylloxera is hard to spot. Often, growers will see the white, waxy material that the aphids secrete, a chalkier type of the honeydew secreted by other aphids. Their bodies are more pear-shaped than oval as are mealybugs. They’re about the same size or slightly smaller than stem-and-leaf aphids with shorter legs and antennae. They come in a variety of colors, including pink, but are mostly white and brown. They’re commonly confused with the larger mealy bugs, because of the white substance they spread. In their winged stage, they can be confused with fungus gnats. Like other aphids, they have small cornicals or “tail pipes” at the end of their abdomen which also distinguishes them from mealybugs.
Because of their size and below-soil habitat they can go unnoticed, even through one or more grow cycles. They can be spotted attached to the sides of grow cups when growers take the trouble to look. Root aphid damage is often mistaken for other problems, especially nutrient deficiencies. Plants that appear to be suffering from magnesium or iron deficiency should be checked carefully for root aphids. In outdoor gardens, root aphids may be accompanied by ants. Once established in soil or hydroponic systems, root aphids are difficult to completely remove.
Lifecycle Root aphids are surprisingly adaptable and their lifecycle can vary tremendously. They reproduce asexually during the growing season. Eggs over-winter in soil or, in warm seasons, are attached to leaves and stems above the root line where they hatch and fall to the ground. The aphid bores into the root, creating scars that leave plants vulnerable to mildew and disease. As infestations increase, “crawlers” will move up the stem to feed. Once a plant is nearly destroyed, some root aphids will develop wings that enable them to seek new plants to attack. In the fall, winged aphids, now male and female, mate in brush and trees and produce more eggs. Ants are known to carry aphids from exhausted plants to un-colonized ones. Damage Damage from root aphids is usually visible in a lack of vigor from plants. Withered, curled, and yellow leaves, similar to signs of nutrient deficiencies, appear and plants fail to reach the size of uninfested plants. Fruits and blossoms on aphid infested plants will be small, stunted, and generally less desirable as nutrition is siphoned away from them.
Attacks from root aphids can leave plants vulnerable to root rot, mildew, and disease. Visible symptoms, like yellowing leaves, often lead growers to consider adding certain minerals, usually magnesium, to their nutrient mixture, often with no result. In addition to greenhouse and garden perennials, various types of root aphids attack rice crops, the roots of a variety of trees including fir, walnut, and hickory. Root aphids can also cause problems for perennial herbs, including those grown in pots. Root Aphid Control Detecting the first signs of root aphids, especially when growing indoors, is crucial to saving your plants vegetating and fruiting abilities. At a certain point, usually sooner rather than later, affected plants and containers should be removed from the grow space completely and destroyed. Waiting for fruits or flowers to mature in an attempt to save something of a crop is not advised. This only gives root aphids a chance to inoculate themselves into your entire grow area. It’s best to start over, sanitizing all containers and growing equipment that’s been used. Indoor growers should clean their entire grow space.
Outdoor plants: Avoid introducing commercial grade soils, including bagged composts, that may contain aphids and their eggs. This is probably the most usual way that aphids have been spread to gardens throughout the country. Buy soil and compost from a reliable, local source, make your own. Attract birds who will pick aphid eggs from trees and the ground. Several types of parasitic wasps attack aphid eggs. Ladybugs will also predate aphids they find on the surface but not those burrowed in the soil. Introduce beneficial nematodes (link below) into soil at the first sign of root aphid infestation or, better, in anticipation of them. Nematodes will attack a number of soil-borne pests yet are harmless to earthworms, pets, and humans. Make sure the soil is moist when applying nematodes. Use Azatrol as a preventive treatment to prevent aphids from feeding on roots. Because it’s slow acting, Azatrol is not a good choice for treating infestations, but can be effective, over time, for minor infestations.
Neem oil can help stop aphid infestations from growing, especially as crawlers move up stems. Do not use insecticidal soaps to control soil-borne aphids. While they will kill crawlers moving up plant stems, they will do little to stop aphids in the soil and may harm your plants’ roots. Pyrethrum-based sprays can be effective if used early enough in the infestation. Water lightly after applying to disperse this chrysanthemum-based botanical into the soil. Reapply every two weeks (eggs in soil may continue hatching) until plants regain vigor and all aphid sign disappears. When removing infected plants, be careful not to drop soil or spread aphids into other parts of your garden. Put plants, roots and all, in a bucket, and take away with minimum disturbance. Removal, in conjunction with preventive spraying, may be your most effective form of control. Indoor plants: Avoid importing soil or other growing medium of unknown origin into your growing space. Many nursery plants, especially those from large, commercial growers, have been found to carry root aphids and their eggs into green houses.
Use yellow sticky traps across indoor grow spaces to discover signs of root aphids on the move. Pay careful attention to your plants. Roots that are visible in grow cups and other hydroponic methods should be periodically inspected. The small, usually white mite stage may be noticeable attached to the sides of grow cups, tanks and trays. Beneficial nematodes introduced to hydroponic solutions at the first sign of infestation may slow the spread of root aphids. With lights off, saturate the growing medium with a solution of Nuke Em (1 oz/ 31 oz water). Slowly pour near the plant stem into the soil and let stand for at least 1 hour — longer contact times are best. Rinse the media before turning lights back on. When treating aphids in various indoor growing mediums, complete and thorough coverage of infected areas is critical to control. Submerge infested grow cups and root balls completely in a pyrethrum concentrate for a half-minute or more, gently swirling roots and medium to insure complete saturation.
Remove badly infested plants. No orchid, no herb or flowering perennial is worth risking your other plants and the health of your entire grow space in an attempt to wait out harvest on an affected plant. Dealing with root aphids, indoors or out, is an evolving and ever-changing set of practices. Don’t be tempted to use harsh, chemical treatments if you already have an infestation. A University of Maryland Cooperative Extension study conducted inside two greenhouses with root aphids on gallardia, aster and boltonia perennials found applications of Talstar (bifenthrin) and Marathon (imidacloprid) applied as a soil drench gave poor results. Keeping aphids out of your garden or grow space in the first place is the most effective practice. And with this problem spreading, it is becoming harder and harder to do.
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Dummer. ゛☀
2017年09月15日
Dummer. ゛☀
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.
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Dummer. ゛☀
2017年09月15日
Dummer. ゛☀
Fungus gnats (families Mycetophilidae and Sciaridae) are a common pest of plants grown indoors, especially where humidity and moisture are high. They’re usually first noticed when the harmless adults are seen flying around house plants or gathered at a nearby window. These non-biting adult gnats can become a flying nuisance. But it’s the larval stage, feeding in the soil, that can damage tender plant roots.
Adults are delicate, grayish black, mosquito-like flies (1/8 inch long) with long legs and one pair of clear wings. They are not strong fliers and emerge from potted plants, especially when watering. Larvae or maggots (1/4 inch) have a shiny black head and an elongated, whitish to transparent body. They are most abundant in damp, rich soils and feed on root hairs, fungi and other organic materials.
Life Cycle Adults live about one week and lay up to 300 eggs in rich, moist soils. Within 4-6 days tiny larvae emerge and begin feeding on plant roots during their two week period. The pupal stage lasts 3-4 days before young adults leave the soil and begin the next generation. The entire life cycle from egg to adult may be completed in as little as 3-4 weeks depending on temperature. Because of their proclivity and relative short gestation, potted plants can host each stage — egg, larvae, pupae, adult — in multiple generations at once. Because of this remedies usually require repeated applications until there are no surviving eggs.
Damage Plant symptoms that indicate fungal gnats are seen as sudden wilting, loss of vigor, poor growth, and yellowing. With severe infestations, a considerable portion of the plants may be lost. Especially prone to injury: Geraniums African violets Carnations Poinsettias Note: Larvae are most damaging to seedlings, cuttings and young plants. Fungus Gnat Control Inspect plants thoroughly prior to purchase for signs of insect pests. Turn up soil carefully near the base of the plant and look for the glossy, clear larvae. Reject any plant sending up flying gnats.
Fungus gnats do best in damp soils; be careful not to overwater, especially during winter months when plants use less. When potting, avoid water holding, organic material such as peat moss that may encourage egg laying. If pests are present, allow the soil to dry to a depth of one to two inches between waterings. This not only kills larvae and inhibits the development of eggs, it also makes the soil less attractive to egg-laying females. Apply Gnat Nix as a top dressing to significantly reduce pest populations. Use Yellow Sticky Traps placed horizontally at the soil surface to capture large numbers of egg laying adults. The gnats are attracted to yellow and are easily removed on the trap before they can lay more eggs.
Mosquito Bits and Microbe-Lift® BMC contain Bacillus thuringiensis var. israelensis, a highly selective biological pesticide that kills damaging larvae, yet is SAFE for fish, wildlife, humans and non-target species. Contains NO harmful residues. Top dress houseplants with Beneficial Nematodes to destroy the larvae stage. Nematodes are microscopic round worms that penetrate fungus gnat larvae, as well as harmful lawn and garden grubs , fleas, and other soil-borne pests (they do not harm earthworms), then release a bacterium that consumes the pest from the inside out. The long-lasting nematodes are safe for use around pets, plants, and your family. Flying Insect Killer, a combination of peppermint, cinnamon and sesame oils, is a non-toxic spray that will get rid of gnats and other insects that gather around windows.
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Dummer. ゛☀
2017年09月15日
Dummer. ゛☀
There are more than 5,000 known species of rust on plants. Common rust (Phragmidium spp.) is a fungal disease that attacks roses, hollyhocks, snapdragons, daylilies, beans, tomatoes and lawns. It is most often found on mature plants where symptoms appear primarily on the surfaces of lower leaves.
Early on, look for white, slightly raised spots on the undersides of leaves and on the stems. After a short period of time, these spots become covered with reddish-orange spore masses. Later, leaf postules may turn yellow-green and eventually black. Severe infestations will deform and yellow leaves and cause leaf drop. Rust diseases are favored by 4 to 8 hours of low light intensity, warm temperatures and moisture — humidity, dew or rain — followed by 8 to 16 hours of high light intensity, high temperatures and slow drying of leaf surfaces.
Black spores are visible on leaves and stems in fall and overwinter inside infected stems which are distinguished by dark, corky blotches at points of infection. The spores are spread by wind or by water splashing back up onto the foliage. Treatment Select rust-resistant plant varieties when available. Pick off and destroy infected leaves and frequently rake under plants to remove all fallen debris. Water in the early morning hours — avoiding overhead sprinklers — to give plants time to dry out during the day. Drip irrigation and soaker hoses can be used to help keep leaves dry.
Use a slow-release, organic fertilizer on crops and avoid excess nitrogen. Soft, leafy, new growth is most susceptible. Apply copper sprays or sulfur powders to prevent infection of susceptible plants. For best results, apply early or at first sign of disease. Spray all plant parts thoroughly and repeat every 7-10 days up to the day of harvest. Effectively treat fungal diseases with SERENADE Garden. This broad spectrum bio-fungicide uses a patented strain of Bacillus subtilis and is approved for organic gardening. Best of all, it’s safe to use — you can treat and pick crops the same day! Containing sulfur and pyrethrins, Bonide® Orchard Spray is a safe, one-hit concentrate for insect attacks and fungal problems. For best results, apply as a protective spray (2.5 oz/ gallon) early in the season. If disease, insects or wet weather are present, mix 5 oz in one gallon of water. Thoroughly spray all parts of the plant, especially new shoots.
Prune or stake plants and remove weeds to improve air circulation. Make sure to disinfect your pruning tools (one part bleach to 4 parts water) after each cut. Use a thick layer of mulch or organic compost to cover the soil after you have raked and cleaned it well. Mulch will prevent the disease spores from splashing back up onto the leaves. Burn or bag infected plants after the growing season (see Fall Garden Cleanup). Do NOT compost.
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Dummer. ゛☀
2017年09月15日
Dummer. ゛☀
Common on many plants and easily recognized, powdery mildew is a fungal disease found throughout the United States. It is caused by a variety of closely related fungal species, each with a limited host range. (The fungi attacking your roses are unlikely to spread to your lilacs). Low soil moisture combined with high humidity levels at the plant surface favors this disease.
Symptoms usually appear later in the growing season on outdoor plants. Powdery mildew starts on young leaves as raised blister-like areas that cause leaves to curl, exposing the lower leaf surface. Infected leaves become covered with a white to gray powdery growth, usually on the upper surface; unopened flower buds may be white with mildew and may never open. Leaves of severely infected plants turn brown and drop. The disease prefers young, succulent growth; mature leaves are usually not affected. Fungal spores overwinter inside leaf buds and other plant debris. Wind, water and insects transmit the spores to other nearby plants. Zucchini, beans, cucumbers, squash, pumpkins, tomatoes, roses and zinnia are especially susceptible.
Treatment Plant resistant cultivars in sunny locations whenever possible. Prune or stake plants to improve air circulation. Make sure to disinfect your pruning tools (one part bleach to 4 parts water) after each cut. Remove diseased foliage from the plant and clean up fallen debris on the ground. Use a thick layer of mulch or organic compost to cover the soil after you have raked and cleaned it well. Mulch will prevent the disease spores from splashing back up onto the leaves. Wash foliage occasionally to disrupt the daily spore-releasing cycle. Neem oil and PM Wash, used on a 7 day schedule, will prevent fungal attack on plants grown indoors.
Water in the morning, so plants have a chance to dry during the day. Drip irrigation and soaker hoses will help keep the foliage dry. Use a slow-release, organic fertilizer on crops and avoid excess nitrogen. Soft, leafy, new growth is most susceptible. Destroy all plant debris after harvest (see Fall Garden Cleanup). Do NOT compost. If disease symptoms are observed, treat plants with one of the following approved organic fungicides: Apply sulfur or copper-based fungicides to prevent infection of susceptible plants. For best results, apply early or at first sign of disease. Spray all plant parts thoroughly and repeat at 7-10 day intervals up to the day of harvest. Green Cure Fungicide contains a patented formula of potassium bicarbonate — commonly used in food products — that kills many plant diseases on contact and provides up to 2 weeks of residual protection. At first sign of disease, mix 1-2 Tbsp/ gallon of water and apply to all exposed surfaces of the plant. Monterey® BI-CARB is a similar product containing micro-encapsulated potassium bicarbonate as the active ingredient. Mix 4 tsps in 2 gallons of water to thoroughly cover foliage.
Effectively treat fungal diseases with SERENADE Garden. This broad spectrum bio-fungicide uses a patented strain of Bacillus subtilis that is approved for organic gardening. Best of all, it’s safe to use — you can treat and pick crops the same day! SNS 244 and Zero Tolerance Herbal Fungicide are made from 100% pure, food-grade ingredients that work fast to kill existing plant diseases and prevent new fungal problems from starting. Indoor growers may want to consider using a Sulfur Burner/ Vaporizer which turns sulfur prills into a fine dust and changes the pH of leaf surfaces. Fungal spores and mold can’t get established on this plant coating. As an added benefit, studies have shown that this dust will eliminate spider mites.
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