cat entfact.* PEACHTREE BORER by Ric Bessin, Extension Entomologist University of Kentucky College of Agriculture The peachtree borer is a native North American pest that causes serious damage to peach, cherry, plum, nectarine, and apricot. Damage is caused by the larval stage, primarily to younger trees. Larvae tunnel into the roots and lower trunks of the hosts feeding on the growing tissue and inner bark. Young trees may be completely girdled and older trees may have their crop bearing capacity greatly reduced. Infested trees may yellow and eventually die as the larvae girdle the tree at the crown. The adult peachtree borer is a clear wing moth with a 1-1/4 wing span. Unlike the majority of moths, these fly during the day and are most active from 10 a.m. to 2 p.m. The female is dark, steel blue with one or two wide orange bands around her abdomen. Her front wings are opaque while the hind ones are clear. The male moth is smaller and more slender. It is also steel blue, but has several narrow-yellow bands around the abdomen. Both pairs of wings are clear. Egg laying begins shortly after the moths emerge and lasts only a few days. The eggs are deposited on the trunk at or near the base. Females lay 500-600 eggs on average. The larvae will begin to hatch in 9 to 10 days. Upon hatching, the larvae wander down the trunk to the soil line and burrow into the bark, often entering through a crack or wound. When full grown, the larva is 1-1/4 in long, cream colored with a dark brown head. The winter is spent as a larva under the bark. In the spring the larva will construct a silken cocoon and cover it with tiny bits of chewed wood. The borer will remain in the pupal stage from 18 to 30 days before emerging as an adult. There is a single generation per year. Infestation by the peachtree borer is often identified by oozing of gum around the base of the tree. The gum is usually mixed with dirt and reddish-brown frass. Frequently empty brown pupal cases can be found around the base of damaged trees, either at the head of the larval gallery or in the soil close to the tree trunk. Prevention Key to Control Control of peach tree borers in commercial orchards relies on preventing the larval establishment underneath the bark. Once under the bark, chemical control is ineffective. Insecticides should be timed to coincide with initial egg hatch in order to be effective. To aid in the timing of sprays, pheromone traps are used to alert producers to the presence and activity of peachtree borer moths. Because egg hatch begins about 9 to 10 days after the moths emergence, insecticidal sprays should be applied 7 to 14 days after the first male peachtree borer moths are captured in the traps. Sprays containing Asana XL, Lindane, Lorsban, or Thiodan are labeled for control of peachtree borer on peaches. Directed sprays should be applied uniformly to the trunk from the base to the lower limbs. Thoroughly wet the bark. Do not allow Lorsban or Lindane sprays to contact fruit foliage. Asana XL and Lorsban have a 14 day preharvest interval, while Thiodan has a 21 day preharvest interval. Asana XL is a RESTRICTED USE insecticide. Pheromone Trapping Pheromone trapping uses chemical lures to attract male moths. These lures are synthetic copies of the chemicals female moths use to attract the mates. Moth captures in pheromone traps alert growers to pest activity and aid timing of insecticide sprays. A trap consists of plastic top and bottom held together by a wire hanger with the lure placed inside. The inner surface of the bottom is coated with a sticky material to hold the insects once they land in the trap. Traps are hung in the tree at eye level, usually one for each ten acres of trees (minimum of two traps per orchard) in commercial orchards. For a list of source of the various types of pheromone traps, see ENT-54, Vendors of Microbial and Botanical Insecticides and Insect Monitoring Devices. Moth activity can occur anytime between mid June and early August. In order to detect the first activity, traps should be hung in tree well in advance of the anticipated flight. Usually this means hanging traps shortly after petal-fall. Trap lures need to be replaced once a month. Traps bottoms should be replaced when the stick surface becomes clogged with other debris. Proper identification of the moths captured in the trap is essential. There are many other moths which may wander into the trap, even other clear wing moths, such as the lilac borer or dogwood borer. Check the description of the male peachtree borers above. The lilac borer has red and black antennae, yellow and red legs, and the front wings are opaque black. The dogwood borer has thin yellow abdominal bars on the abdomen similar to the male peachtree borer, but the tips of the front wings have a broad black tips. Worming Trees May be an Alternative for Some Before the development of chemicals for controlling peachtree borers, producers relied on digging the borers out of the bark by hand. This is still an alternative for backyard gardeners in the fall. Dirt should be removed from around the base of the tree to a depth of 4 to 5 inches. Care should be taken not to cut the sound bark more than necessary, and cutting should be done vertically. Carelessness may result in more damage to the tree than the damage that would have been caused by the borers! After the larvae have been located and removed, the dirt should be replaced around the base of the tree to the original level. APPLE INSECT CONTROL WITH REDUCED INSECTICIDE USE by Ric Bessin, Extension Entomologist University of Kentucky College of Agriculture Control of the major insect pests of apples for commercial production sometimes involves timely insecticide applications. Unlike some crop pests, pests of apples can be very elusive and damage can often occur without individual pests being seen. To maintain healthy, productive trees and fruit, producers should recognize what the pests to look for, understand pest biology, use appropriate preventive measures, and apply timely controls when needed. The "Kentucky Commercial Tree Fruit Spray Guide," ID-96, provides a listing of the available insecticides and guidelines for applications at regular intervals for commercial producers, while "Disease and Insect Control Program for Home Grown Fruit in Kentucky," ID-21, is the corresponding guide for home owners. Following these guidelines, a producer should be able to maintain a protective insecticidal shield against insect infestation. These guidelines are designed to protect against nearly any insect pest problem in tree fruit that can occur in the commonwealth throughout the year. However, experience has shown us that all orchards do not have all pests during the whole growing season. Regular cover spray schedules provide preventive control without regard to whether the pests are present or whether the pest populations are large enough to be economically threatening. An important IPM concept is that pest populations need to be present in large enough numbers in order to justify the cost of pesticide applications. Applying unnecessary insecticide applications can be very costly and can lead to the development of insecticide resistance or secondary pest outbreaks. Monitoring Which insecticide applications are unnecessary? These will be different for different orchards. They are determined through the use of pheromone traps and timely examination of the trees. Typically, trees should be examined once a week in the spring and early summer, and once every two weeks there after. Pheromone traps should be examined daily until initial catches are made then once a week until harvest. Key pests to control in an orchard insect management program include codling moth, plum curculio, and San Jose scale. Other secondary pests include European red mites, rosy apple aphids, red- banded and oblique-banded leafrollers, green fruitworms, leafhoppers, Japanese beetles, and woolly apple aphids. The secondary pests are usually less threatening, in that use rescue treatments are usually effective means of control when economic infestations are found through scouting. Predicting Insect Development Using Degree Days Temperature plays the major role in determining the rate of insect development. Each insect has an optimum temperature at which it will develop at its fastest rate. For each insect there is a minimum temperature (termed threshold temperature) below which there is no development, as well as a maximum temperature (termed upper cutoff) above which development stops. By using the relationship between temperature and rate of development, when insects will pass through certain stages and cause crop damage can be predicted. This method of estimating time is called the degree day method. A degree day is the same as an average of one degree over the threshold temperature for a 24-hour period. The ability of these models to predict insect development depends partly on the acurracy of the data used in determining degree days. The easiest way to calculate degree days each day is to subtract the threshold from the average daily temperature. The average daily temperature can be determined by averaging the minimum and maximum temperature over a 24-hour period. Minimum and maximum temperatures should be recorded from a Min/Max thermometer about the same time each day, preferably in the mid morning or late afternoon. For example, if the min/max thermometer indicates a minimum temperature of 45øF and a maximum of 75øF, then the average temperature for the day was (75+45)/2 = 60øF. If the threshold temperature was 50øF, then 10 degree days would have accumulated. With apple IPM, degree day models are used primarily for two insects, San Jose scale and codling moth. Degree day accumulations are used to predict when certain biological events occur, such as egg laying, egg hatch, or scale crawler movement, they also synchronize for insecticide sprays. For both of these pests, degree days are accumulated after certain events, termed biofixes (usually based on pheromone trap catches). These occur in the early spring. Orchard Insect Management Program The key to successful insect management in apple orchards, whether the orchard is managed by a conventional program or a reduced-pesticide integrated pest management program, is effective early season control. To achieve this, insecticide sprays are required during the following stages; dormant or delayed-dormant, pink, and petal-fall. The combination of these applications will help to manage some of the more difficult to control pests. The dormant or delayed-dormant application is used to control several troublesome insects including San Jose scale, European red mite, and rosy apple aphid. This is an oil application. Usually 1 to 4 gal. of oil per 100 gallons of spray is used. Petroleum oils function as insecticides and miticides by suffocating eggs and other susceptible stages of some insects. Therefore thorough coverage is essential! Sprayers should be properly calibrated and the tree adequately pruned to allow for complete coverage. Timing of the dormant oil can influence the degree of control of some pests. Apply a delayed-dormant oil spray unless San Jose scale is a major problem. Oil sprays applied at green-tip provide better control of European red mites and moderate control of San Jose scale. Dormant oil applications provide the best control of San Jose scale and should be used where infestations are heavy. Failure to apply either a dormant or delayed-dormant oil may require that additional inseason treatments be applied. These are not only more costly, but are more disruptive to beneficial arthropods that keep secondary pests under control. Insecticide sprays timed at the pink and petal-fall stages are required to control insects that cause cat-facing of the fruit. Cat- facing insects include plum curculio, stink bugs, and plant bugs. Plum curculio causes characteristic crescent-shaped wounds to the fruit by feeding and egg laying. Stink bugs and plant bugs damage fruit while feeding with their piercing sucking mouthparts. These wounds often develop into sunken pits or dimples on the fruit as the uninjured parts of the fruit expand more rapidly during development. Currently, because there is no effective method to predict when damage will be caused by these pests, insecticides should be included in the cover sprays at the pink and petal-fall stages. With the exception of codling moths and San Jose scale, other apple pests can be effectively controlled with rescue treatments based on weekly examinations of the trees and fruit. Reduced pesticide programs for codling moth and San Jose scale involve scouting, pheromone trapping, and the use of degree day models. PLUM CURCULIO MANAGEMENT by Ric Bessin, Extension Entomologist University of Kentucky College of Agriculture Plum curculio is a native pest of North America that has caused considerable problems in orchards throughout Kentucky. While it has only a single generation in Kentucky, it can cause serious early season fruit damage to apple, pears, peaches and other stone fruits. The adult is a typical snout beetle, 1/4 inch long, dark brown in color with patches of white or gray. There are four prominent humps on the wing covers. The snout is 1/4 the length of the body, with mouth parts located at the end. Plum curculio overwinters in the adult stage in ground litter or soil usually outside the orchard. Adults migrate into the orchards each spring. Often border rows near woods are the first to show injury. The adult curculio becomes active in the early spring where it flies to trees and feeds on buds, flowers and newly set fruit over a five to six week period. This results in cat-facing facing of the fruit because of plum curculio feeding and egg-laying injuries. The female adult cuts a hole in the fruit with her mouthparts and hollows out a small cavity then turns and deposits an egg in the cavity. She then cuts a crescent-shaped silt which extends beneath the egg so as to leave the egg in a flap of flesh. Injury will appear as a 1/8 inch crescent- shaped cut on the fruit. This prevents the egg from being crushed by the rapidly developing fruit. After about five days, the larvae will hatch burrow into the fruit. The larva is a leg-less grayish white grub with a brown head. Its length will be about 1/3 inch when full grown. When the larvae are fully developed, they will leave the fruit through clean-out holes. No frass or webbing will be evident. Frass is usually found around the calyx end on codling moth damaged fruit. Surface feeding and egg-laying by the overwintering adults can scar or misshape the fruit by harvest, while feeding by the larvae causes premature drop of the fruit. In peaches, gummy material can often be seen at the location of the wound. These insects are active primarily at night and serious damage may appear in orchards that have been scouted rigorously even though the adults were not detected. Currently there are no methods to accurately predict when plum curculio damage will occur. Newly emerging adults in the late summer will feed on apples for a short period of time. They cause round, cylindrical feeding wounds in the side of the fruit that penetrate about 1/4 inch often lead to localized rots on the fruits. Control Adults control is accomplished by insecticide applications timed at the pink and petal-fall stages for apples, and the petal-fall and shuck-split stages in peaches and cherries. Serious plum curculio damage is usually restricted to orchards that do not use both these insecticide applications. Home gardeners can help reduce future problems by picking up these damaged apples as they fall off the tree and destroying them before the adults emerge. In apples, the larvae will only complete development in fruit drops. ENTFACT-203 CODLING MOTH by Ric Bessin, Extension Entomologist University of Kentucky College of Agriculture The codling moth larva is one of the very destructive pests introduced from Europe by settlers. Female moths lay the scale-like eggs singly on developing fruit or adjacent leaves or stems just after sundown each night. Upon hatching the larva enters into the calyx end or side of the fruit then tunnel to the center where they feed and develop. Brown frass is often noticed near the calyx end of the developing fruit. The larva is pinkish to white in color with a brown head and can reach 3/4 inch. Larval development is completed in 3 to 5 weeks. Larvae exit the fruit to pupae in a thick silken cocoon on the bark or other protected areas. The fully developed larva is the overwintering stage. Pupation occurs in spring beginning about the same time as bloom with adults first active in late April or early May. In Kentucky, there are three generations each year. The adult is about 3/8 inch, gray, with distinctive bronze areas on the bottom 1/3 of the wing. Control of codling moth in commercial orchards relies on three tools; regular examination of the trees and fruit (termed scouting), pheromone trapping, and the use of weather monitoring and degree day models. Orchards should be scouted on a weekly basis for insects and mites beginning at the half-inch green stage in the early spring until harvest. Closer to harvest every other scouting trip may be omitted such that visits are no more than two weeks apart. Pheromone Trapping Pheromone trapping uses chemical lures to attract male moths. These chemical lures are synthetic copies of the chemicals female moths use to attract males for mating. A trap consists of plastic top and bottom held together by a wire hanger with the lure placed inside. The inner surface of the bottom is coated with a sticky material to hold the insects once they land in the trap. Traps are hung in the southeast quadrant of the tree at eye level, usually one for each ten acres of trees (minimum of two traps per orchard) in commercial orchards. Home owners have a few different options for controlling codling moths. Home owners can use pheromone traps to time insecticide sprays, or to "trap out" all the male moths. This involves using enough pheromone traps such that all of the male moths are captured before the female moths mate. Female moths are then able to lay only unfertilized eggs that will not develop. Typically, 2 to 4 traps per tree are required for this to be successful. This is less effective if there are additional sources of mated females, such as other trees in the neighborhood or wild hosts. Traps should be put out at the pink stage of bud development. Every month, pheromone lures need to be replaced. Codling moths can be distinguished from other insects in the traps by their bronze wing tips. For a list of the sources of various type of pheromone traps, see ENT- 54, Vendors of Microbial and Botanical Insecticides and Insect Monitoring Devices. Degree Day Accumulation Initial trap catches in the early spring are termed biofixes. This information will be used to predict when egg hatch will occur and synchronize insecticide sprays. In commercial IPM orchards, inclusion of an insecticide in the cover sprays is recommended as long as pheromone trap catches exceed an average of five moths per trap per week. The biofix for the codling moth is the starting date of the first sustained flight of male moths captured in pheromone traps. Generally, this is when the fifth moth has been captured in the trap. A few moths often emerge very early in the spring ahead of the rest. Using the fifth moth as the biofix better represents when the majority of the codling moths begin to emerge. This usually occurs just after petal fall. Codling moth traps need to be examined daily in order to know exactly when the biofix occurs. After the biofix has occurred, degree days are calculated on a daily basis and a running total is kept (see "Predicting Insect Development Using Degree Days" in ENTFACT-201). The codling moth has a 50øF threshold temperature. These degree day accumulations are compared with the target values in the following table. DD Target Action taken when target reached 250 Egg hatch begins. An insecticide spray is recommended. If codling moth are abundant (more than 10 per trap per week), a second spray may be necessary 7 to 10 days later. 1000 When 1st generation moth begin to fly. Use their emergence as the next biofix. 1300 About when 2nd generation egg hatch begins. An insecticide spray is recommended. If codling moth are abundant, a second spray may be necessary 7 to 10 days later. Codling moth trap catch records need to be maintained throughout the summer to monitor additional generations. However, after the initial biofix it is only necessary to examine the traps twice a week. A threshold of five moths per trap per week is used to determine if there are sufficient levels of moths to warrant an insecticide application. Trunk Banding Another tactic that can be used by home owners is the use of cardboard bands placed around the trunk of the trees to serve as pupation sites for the wandering larvae. A four to six inch band encircling the trunk or scaffold limbs will attract the larvae. Bands should be in place before larvae begin to leave the apples in search of pupation sites and removed and destroyed before moth emergence begins. Bands should be placed on trees in August to capture overwintering pupae and removed and destroyed in December. Bands can also be used in the summer to capture pupae from the summer generations, but timing is more difficult. Sanitation Home owners should also pick up a destroy fallen fruit. Often fruit that drop prematurely are infested with either codling moth or plum curculio larvae. For more information on reduced insecticide apple management, see ENTFACT-201, Apple Insect Control with Reduced Insecticide Usage. SAN JOSE SCALE by Ric Bessin, Extension Entomologist University of Kentucky College of Agriculture San Jose scale is an extremely important indirect pest of apples, pears, peaches, and plums. It is a sucking inject that injects a toxin into the plant as it feeds causing localized discolorations. The presence of reddish blemishes on fruit at harvest indicates potentially damaging numbers on the trees. Left uncontrolled, San Jose scale can kill the entire tree in a couple years. If such damage is noted, inspect trees for scale, especially one year-old wood. Purplish-red halos on young bark are indications of scale infestation. Often this very small insect goes unnoticed until large populations have developed. San Jose Scale overwinter as immature scales. In the spring, the tiny winged males emerge and mate with the wingless females, and about one month after the begin of the male flight, the first crawlers can be seen. Eggs are not seen because females give birth to live crawlers. These tiny yellow insects move around randomly on bark and foliage before settling down permanently. A few days after settling down, crawlers will secrete a waxy covering over their body that will protect them from pesticides. From this point on female scales will not move. Males will remain in one location until maturity, at which time the winged males will seek out females and the cycle will begin again. Pheromone Trapping & Degree Day Accumulation Pheromone trapping involves the use of chemical lures to attract male scales. These chemical lures are synthetic copies of the chemicals female scale use to attract the male for mating. A trap consists of a lure suspended between the two sticky sides of a tent-like trap. Pheromone traps for this insect should be placed in scale infested trees either prior to or during bloom. For a list of the sources of various types of pheromone traps see ENT-54, Vendors of Microbial and Botanical Insecticides and Insect Monitoring Devices. Lures should be replaced monthly. Male scales are extremely small gnat-like insects, so traps need to examined carefully. Scales appear as a fine dust on the trap, usually concentrated on the sticky surface near the pheromone lure. Trapping of scale is used to indicate when the activity of the male scales begins. The date that the first males are caught in the trap is termed the biofix date. Male flight usually occurs after petal fall (mid to late April). Pheromone traps need to be examined daily in order to known when biofix occurs. After the biofix has occurred, degree days are calculated on a daily basis and a running total kept (see "Predicting Insect Development Using Degree Days" in ENTFACT-201). San Jose scale has a 51øF threshold temperature. These degree day accumulations are compared with the target values in the following table. Detecting Crawler Movement Crwler movement begins sometime between mid-May and mid-June. Dark double sided sticky tape should be used to monitor for emerging crawlers. A small amount of tape is applied tightly to around a scaffold limb after removing surface debris with sandpaper. A limb with a known infestation should be selected. Crawlers will appear as extremely small lattened yellowish insects which can be seen with a hand lens on the tape (especially around the edges). Within two days, the crawlers will find a permanent resting spot where they will feed and begin to secrete a protective waxy covering. There are two generations each year. DD Target Action taken when target reached --------- -------------------------------------------------------- 300 Place a piece of black tape, with sticky side out on an infested scaffold limb. Begin examining tape at least twice weekly for minute scale crawlers. 380-400 Crawler emergence should begin. 600-700 Maximum crawler movement. This is the best time for an insecticide spray. Effective control of San Jose Scale in apples is obtained with dormant oil sprays and a late spring insecticide spray aimed at the immature, crawler, stage. Sprays directed against crawlers also protect fruit from infestation. Sprays should be timed about one week after the first crawlers are seen. If populations are heavy, a second application two weeks after the first should be used. These applications aimed at the crawlers have little effect on the adult scales. Because San Jose Scale occur on all parts of the tree, spray coverage as well as are very critical to effective control. Although there is a second generation later in the summer, crawlers emerge over an extended period of time making insecticidal control of this generation impractical. For more information on reduced insecticide apple management programs, see ENTFACT-201, Apple Insect Control with Reduce Insecticide Use. EUROPEAN RED MITES by Ric Bessin, Extension Entomologist University of Kentucky College of Agriculture The European red mite is another introduced pest in the US. It is a pest of nut, pome and stone fruits, and some berries. This pest damages leaves and causes fruit russetting. European red mites can have 6 to 8 generations per year, depending on the temperature. Summer generations may develop in as little as 14 days. The adult female mites are brick red with white spots at the base of six to eight hairs on their back. The male mite is more slender and lighter in color than the female, with a more pointed abdomen. Eggs are red, globular and somewhat flattened (onion shaped) with a slender stalk on the upper side. European red mites overwinters as eggs laid in roughened bark around the bases of buds and spurs on small branches. During the summer eggs are laid on the underside of leaves. Egg hatch in the spring is closely correlated with bud development and begins close to the tight cluster stage. During the summer, eggs require 7 to 14 days to hatch. All active stages of the European red mite injure the foliage by feeding with piercing mouthparts and removing cell contents, including chlorophyll. Moderate to high numbers of mites can cause the leaves to initially turn pale and with continued feeding the leaves turn bronze. Heavy mite feeding early in the season can reduce tree growth, yield, and also effect fruit bud formation for the following year. Some apple cultivars, such as 'Red Delicious' and 'Braeburn', are more prone to mite buildup and injury. European red mites are rarely a problem on backyard apple trees. Predatory mites, ladybird beetles and the six-spotted thrips help to maintain these European red mite at nondamaging levels. This mite is considered a secondary pest, it typically only builds to damaging levels after its natural enemies have been depleted by insecticide applications used to control codling moth or other pests. Minimizing insecticide usage and selecting insecticides that are least toxic to beneficial organisms will help to minimize problems with this mite. Monitoring To monitor for mites, examine 5 hardened-off leaves from each of four scaffold limbs per tree. Commercial orchardists should examine at least 5 tree per acre. Certain varieties, such as Red Delicious, are more likely to develop large numbers of mites, so be sure to make samples representative of the varieties in the orchard. Using a hand lens, count all active stages of pest and predatory mites. Predatory mites are more active and are tear-drop shaped. Determine the average number of European red mites per leaf. The economic threshold for the mites varies with the time of year. A miticide is recommended early in the year (until April 1) if numbers of active mites exceed an average of 5 per leaf, during April and May when mite numbers exceed 10 per leaf, or the rest of the season if mite numbers exceed 15 per leaf. Some insecticide cover sprays are less severe on mite predators, consult ID-92, "Commercial Tree Fruit Spray Guide", for a list of those sprays and there ratings against mite predators. Management Overwintering mite eggs should be controlled through the use of a delayed-dormant oil treatment, anytime between just before bud swell until half inch green. Control with dormant oil improves the closer to egg hatching. Management of mites during the growing season is based on scouting and the use of miticides or summer oil treatments as needed. Often when heavy summer infestations exist, a second miticide treatment may be required 10 to 14 days later. Horticultural oils provide an alternative to traditional synthetic miticides, are able to kill all mite life stages, and are less toxic to the applicator. While effective control can be obtained with summer horticultural oil treatments, caution is advised as these may be incompatible with some other pesticides (particularly sulfur containing products), are phytotoxic at higher temperatures (above 90øF and high humidity), and may affect fruit finish on some varieties. NUT WEEVILS by Ric Bessin, Extension Entomologist University of Kentucky College of Agriculture Nut weevils can be very serious pests of native and non-native nut trees. These damaging insects begin to attack the kernels in the developing nuts while the nuts are still on the tree. However, problems often are not noticed until the nuts are harvested and opened. Occasionally, these weevil grubs are found in homes or other places nuts are stored. Pecan Weevil, Curculio caryae This is a serious late season pest of hickory and pecan. The greatest damage is caused by the grub that feeds directly on the developing kernel. Adults are reddish-brown and densely covered with olive-brown hairs and scales. Body length is about 3/8 inch long exclusive of the snout. The female has a snout as long as her body, while the male's is about half that of the female's snout. Two types of damage are caused by this insect; mid-season adult feeding on young nuts causing premature nut drop, and grub damage to the kernels that usually occurs after shell hardening. Adults weevils emerge from the ground in late August through September, about the time nuts begin to harden. Peak periods of adult emergence usually follow heavy rains. After the nut kernels have hardened, the female uses her long snout to chew a hole in the side of the nut and deposits her egg in little pockets in the nut. Creamy white grubs with reddish brown heads hatch and feed inside the nuts during the fall, reaching 3/5 inch in length. When mature, the grub chews a perfectly round 1/8 inch hole in the side of the nut and fall to the ground in late fall or early winter, usually between late September and December. They make earthen cells in the ground where they remain as a grub one to two years. Most of the grubs will pupate the following fall. Some, however, do not pupate until the fall of the next year. Adults emerge during the summer following pupation. The entirelife cycle requires 2 to 3 years to complete, most of it in the soil. Weevils usually move only a short distance after emerging and often attack nuts on the same trees year after year, so long as there is a crop of nuts. Weevils apparently prefer trees growing in low areas or those near hickory trees. Early maturing varieties are most susceptible to the weevils. Hickory nuts are attacked by the pecan weevil as well. Monitoring for Pecan Weevils Trees can be jarred trees beginning in mid August to determine when to apply insecticides. Place a large harvesting sheet under the trees and jar the limbs with a padded pole. The adults weevils will fall onto the sheet and remain motionless for a short period. When three or more weevils are jarred per tree, insecticide applications should begin. Peak emergence cycle usually follow rains. Otherwise spray applications should begin when shell hardening begins and repeated at 10 to 14 day intervals. Sevin, Imidan, and Asana XL can be used to control pecan weevils on pecan. Asana XL is a restricted use pesticide. Those not prepared to spray can reduce weevil injury by periodically shaking weevils onto a harvesting sheet. Dislodged beetles usually remain motionless on the sheet and can be easily collected and destroyed. Shaking should begin after the first heavy rain in early August and continue through mid-September or until no weevils are collected. Chestnut Weevil Lesser Chestnut Weevil and Larger Chestnut Weevil Curculio sayi and Curculio caryatrypes Of the larger and lesser chestnut weevils, the lesser chestnut weevil is the more common of the two species of weevil infesting chestnuts in Kentucky. These weevils breed exclusively in chinquapin, American and Chinese chestnuts. At one time these weevils were common, but since the passing of the american chestnut they have become much less common. The 1/4 inch lesser chestnut weevils emerge from the ground beginning in late May until July, about when the chestnuts bloom, but do not lay eggs until the fall. Egg laying begins when the nuts are nearly mature and most eggs are laid after the burr begins to open. Eggs are usually laid in the downy inner lining of the brown shell covering the nut. Eggs hatch in about 10 days and larval development is completed 2 to 3 weeks later. Soon after the nut fall to the ground, the grubs chew a circular hole in the side of the nut to enter the soil. Most of the lesser chestnut weevil grubs overwinter the first year as grubs, pupate the following fall, and overwinter the following winter as adults. Some pass two winters in the grub stage and a third winter as adults before emerging from the ground. The life cycle is completed in 2 to 3 years. Biology of the larger chestnut weevil differs from the lesser chestnut weevil. Adults begin to emerge in late July and August. The adult is 3/8 inch long exclusive of the snout. The female has a 5/8 inch beak and the male's is 1/4 inch. Larger chestnut weevils begin egg laying soon after emerging, before egg laying begins with the lesser chestnut weevil. Eggs hatch in 5 to 7 days and the larvae feed for 2 to 3 weeks before leaving the nut. Larger chestnut weevil grubs chew and exit hole in the side of the nut and drop to the ground usually before the nuts fall. Grubs overwinter in earthen cells in the ground. Pupation and adults emergence takes place the following summer. A few grubs will overwinter a second year before pupating. The life cycle is completed in 1 to 2 years. Management Weevil infestations can be reduced by picking up chestnuts daily and after curing, heat them to 140 F for 30 minutes to kill the larvae in the nuts. A cold treatment of holding the nuts at 0 F for four days may also be effective, but it may also affect the nuts flavor. Sanitation is important, always collect and destroy fallen nuts before the larvae have a chance to escape and enter the soil. Only one insecticide, carbaryl (Sevin) is registered for use against chestnut weevils on chestnuts. Trees can be jarred similar to monitoring for pecan weevils to determine the presence of adult weevils. STRAWBERRY PESTS by Ric Bessin, Extension Entomologist University of Kentucky College of Agriculture Strawberry Root Weevils Several species of root weevils feed on the young roots and crowns of strawberry plants. Although adults will eat notches in the leaves, this damage is unimportant. However, the grubs of these weevils can cause serious damage by tunneling in roots and crown of plants. Damaged plants are stunted and darkened with leaves closely bunched. Plants may be weakened or ever killed. Often the damage is restricted to a circular area in field due to the tendency of adults to gather in large groups. The adult stage of these insects is a small, dark snout beetle with rows of pits along their backs. The different species will differ slightly in size and color. The strawberry root weevil is black to light brown and 1/5 inch, the rough strawberry weevil chocolate brown and 1/4 inch, and the black vine weevil is black with small flecks of yellow on its back and 2/5 inch. The grubs are white, 1/4 to 1/2 inch long, and a characteristic "c" shape. These grubs can be distinguished from other soil grubs because they are smaller and legless with a lighter colored head. Root weevils overwinter in the soil as grubs that pupate in the spring. Adult beetles emerge in late May through June, feed at night on foliage leaving characteristic leaf notching, and hide during the day. After feeding for a short as 10 to 14 days (strawberry root weevil) to as long as 30 to 60 days (black vine weevil) they begin laying eggs in soil near strawberry plants. The eggs hatch in late summer or early fall and the grubs start feeding on the roots. Most damage is caused by grubs after resuming feeding in the spring. To prevent spread of root weevils to new beds, plow under old beds as soon as possible. Post harvest foliar sprays to control adult weevils prior to egg laying is recommended at renovation. Growers should watch for leaf notching as an indication of adult emergence. Meadow Spittlebug The meadow spittlebug is an annoying pest on strawberries that can stunt plants and reduce berry size. More important to some producers, particularly u-pick growers, is the annoyance that spittle masses cause pickers. Although the spittle is harmless, pickers object to being wetted by the insect excretion. Spittlebugs can be recognized by the white masses of wet foam or spittle on leaves, petioles, and stems. The tiny green nymphs produce the spittle covering to protect themselves from predators and desiccation. Newly emerged adults are bright green and darken to a dull brown. Nymphs feed for five to eight weeks before entering the adult stage. Adults are seen on foliage from late May until frost, but usually go unnoticed because they produce no spittle. Adults lay their eggs in the stems and leaves of plants from July through October. There is only one generation per year. Initially the nymphs feed at the base of the plants, but later move up to the tender foliage. Feeding may cause leaves to become wrinkled and dark-green. While fruit may be stunted, significant yield loss seldom occurs. High spittlebug populations are often associated with weedy fields, so proper weed control along with other practices encouraging healthy plants are important. Prebloom sprays are rarely necessary for spittlebugs, but u-pick growers should keep populations less than one spittle mass per square foot through prebloom to appease customers. Begin estimating spittlebug density at 10% bloom by inspecting five to ten 1-square-foot areas per acre of strawberries at two week intervals. It will be necessary to spread plants and inspect the crowns as well as leaves and stems. Control is considered at one spittlebug per square foot (u-pick) up to four to five per square foot. Tarnished Plant Bug Tarnished plant bug is a common sap-feeding insect attacking a wide range of economically important plants. The tarnished plant bug can cause considerable damage to strawberries by puncturing young fruits before receptacles expand. These damaged areas do not develop along with the rest of the berry, resulting in misshapen "catfaced" fruit. The damage may range from slight deformation to complete loss of market value of the crop. The tarnished plant bug overwinters as an adult in leaf debris and other protected areas. Adults are recognized by their greenish-brown body marked with yellowish and black dashes with a characteristic small yellow-tipped triangle behind the head. Adults become active in April and begin egg laying in weeds. The tiny nymphs are slender, pale green insects that resemble aphids. However, aphids have a pair of cornicles (tail pipe-like tubes on top of their abdomen)and tarnished plant bugs do not. The nymphs turn brown during the last instar. The entire life cycle is completed in 30-40 days with two to four overlapping generations occurring each year. Most damage takes place just after petal fall. Early June bearing varieties can escape most tarnished plant bug injury because pest populations are small and consist of less damaging early instars. Late maturing cultivars are more susceptible to damage. Plantings near alfalfa fields, woods, or weedy areas more prone to damage. Alternative hosts, especially weeds and seed-producing plants should be eliminated around the planting. Regular mowing or weeding may help, but should be avoided just before or during the blossom period. From pre blossom until harvest, shake blossom or fruit clusters from ten to fifteen plants per acre over light colored pan. Treatment is suggested when levels reach an average of 0.5 nymphs per cluster. Sap Beetles Sap beetles are attracted to ripe, damaged, or cracked fruits. Any injury exposing plant sap that has a chance to ferment will attack sap beetles. Damage may appear as small holes in the bottom of the berry, or as large sections devoured from the side. Beetles may spread rot-causing disease organisms from berry to berry. Sap beetles are mostly small black or dark insects that are flattened and broadly oval. Most feed on plant sap that exudes from wounds on ripe and decaying fruit or fungi. A common sap beetle in Kentucky is the four spotted sap beetle known as the "picnic beetle". This beetle is 1/4 inch with four yellowish spots on its black wing covers. The best management practice is sanitation. Keep fields as clean of ripe fruit as possible through timely removal of damaged, diseased, and overripe fruits. Sap beetle problems often occur after a rainy period during harvest, when there may be a buildup of overripe fruit. Sap beetle traps are sometimes used, but there is no convincing evidence of their effectiveness and are not a replacement for proper sanitation. Sap beetle traps are placed outside the field, between field margins and wooded areas. This is to intercept beetles on their way to the crop. Any container of fermenting plant juices will attract sap beetles. Common baits include stale beer, molasses and water with yeast, vinegar, and overripe fruit from the field. Beetles fall into the container and drown. Sprays for sap beetles are available but difficult to use because they are applied to a crop that is ready for harvest. Therefore, selecting an insecticide with a short harvest interval is essential. Sprays should be applied only if absolutely necessary. Label directions should be read and followed carefully. Slugs Slugs range from yellow to black and may be several inches long. They feed by rasping ragged holes in plant surfaces. Because of the tell-tale slimy trails, left on fruit surfaces, slug damage is easy to verify. Because slugs have no shell, they require a damp, moist environment in order to survive. Strawberry fields with excessive mulch or litter on the soil and dense growth of foliage are attractive to slugs. Most injury occur during damp rainy, spring months. Control of weeds, removal of excessive mulch, and planting at lower densities may reduce slug infestations. Various slug traps have been tried, including the stale beer trap. Traps are unlikely to be practical in commercial plantings, and their effectiveness under field conditions remains unproven. Toxic baits are available for slugs and snails, but this control method is usually ineffective. Most frequently, prevention through cultural management, including incorporation of trickle irrigation, is suggested. Two-Spotted Spider Mite Two-spotted spider mites are common on many species of cultivated and weedy plants. These mites can overwinter on the undersides of strawberry leaves close to the ground. Mites feed by piercing tissue with their mouthparts and extracting cell contents. Damaged leaves may take on a stippled or bronzed appearance. High populations of mites can weaken strawberry plants and there may be a visible webbing on the undersides of leaves and between leaflets and stems. Feeding by spider mites reduces vigor and yield and may lead to stunting or death. Two-spotted spider mites are light to dark green with two distinctive black spots on the abdomen. Eggs are spherical and clear when first laid. After hatching the larva has three pairs of legs, but later stages will have four pairs. Males are smaller with more pointed abdomens than females. Females can lay 200 eggs, and during hot, dry weather the life cycle may be completed in 7 days. Because mites can be a problem at any time of the year, plants should be monitored throughout the summer. Growers should pay particular attention to fields during hot, dry weather and fields with a history of mite problems. To monitor for mites, walk diagonally across the field and randomly pick one mature leaflet from every other row until 60 leaflets are collected. If 25% of the leaves are infested, a miticide spray is recommended. Indiscriminate use of pesticides can create mite problems. Pesticides need to be selected which have little impact on natural enemies of mites. Guthion, Vendex, Captan, Ronalin, and Thiram have little effect on predatory mites. Effective control of mites requires thorough coverage of the undersides of leaves. Coverage can be adjusted through nozzle selection and placement, sprayer pressure, spray volume, and tractor speed. GRAPE INSECTS by Ric Bessin, Extension Entomologist University of Kentucky College of Agriculture Grape Berry Moth The grape berry moth is a key pest of grapes that is distributed in the United States east of the Rocky Mountains, and in eastern Canada. The larvae of this insect can cause serious damage to commercial vineyards by feeding on the blossoms and berries. Infested berries may appear shriveled with fine webbing. Damage by grape berry moth may increase mold, rots and numbers of fruit flies. While grape berry moth larvae may only damage a few berries in a cluster, it is impractical for growers to remove damaged berries and webbing from clusters. Hosts include wild and cultivated grapes. The adult moth is small, active, and about 1/4 inch long. When it is at rest with its wings folded, there is a brown band across the middle of the insect, the hind portion is gray-blue with brown markings, while the front portion is gray-blue without markings. The full grown larva is 2/5 inch long, pale olive-green, and can have with a purplish tinge from the food it has eaten. The pupa is about 1/5 inch long, greenish-brown to dark brown and found under a flap cut in the leaf surface. The grape berry moth overwinters as a pupa in leaf litter under vines. Adults begin to emerge in late May and lay eggs of the first generation singly on fruit stems just before blossom time. Eggs hatch in about 5 days. Under a flimsy web, the larvae feed for about 21 days on the blossoms and young fruit. In mid to late July, larvae move to leaves where they make a semi-circular slit, fold the flap over themselves and pupate. Adult moths emerge from the pupae in 10 to 15 days. Moths begin laying eggs for the next generation after 4 to 5 days. There may be 2 or 3 generations per year. Larvae of the 2nd and 3rd generations enter berries and feed within, passing from one berry to another under protection of webbing. Some of the cocoons of the 2nd or 3rd generations fall to the ground where they overwinter. Webbing over blossoms and berries, and leaf flap cocoons are indicative of grape berry moth. In winter, the cocoons may be found in leaf litter under the vines. Clean up or bury leaf litter under vines in winter to eliminate over wintering pupae. Although larvae first appear when the grapes are in bloom, insecticides should not be applied until the berries are the size of small peas so as not to destroy beneficial pollinators. Insecticidal control of second generation is more difficult due to an extended flight period of moths as well as the difficulty of getting adequate spray coverage inside the cluster as berry size increases. Pheromone traps are available to monitor for adult moth activity and enhance timing of insecticides for grape berry moth control. Recent studies in some states have shown mating disruption with synthetic pheromones to be an effective alternative in situations where there is no immigration of moths from outside sources. Mating disruption relies on releasing enough of the pheromone in the vineyard so that males cannot find female moths. Pheromone is imbedded in 8-inch plastic twist-ties using 400 twist ties per acre. Commercial systems available for mating disruption for this insect are recommended for vineyards at least 5 acres in size. Grape Phylloxera Grape phylloxera is native to eastern United States, but has been distributed to other grape regions of the U.S. and is also established in Europe where it is of great economic importance. The leaf galls caused by grape phylloxera are unsightly and do little damage, however, infestation of the roots can be difficult to control and can lead to decline of vines. Severe infestations can cause defoliation and reduce shoot growth. Hosts include cultivated and wild grapes. The wingless forms of the insect are very small, yellow-brown, oval or pear-shaped, and aphid-like. The winged forms, which are less apt to be seen, are also aphid-like, except that wings are held flat over the back. Neither winged nor wingless forms have cornicles, tail pipe-like structure on the top of the abdomen, as aphids do. The presence of grape phylloxera is best recognized by characteristic galls it produces on the leaves or roots. Leaf galls are wart-like, about 1/4 inch in diameter, and are familiar to anyone growing grapes. Root galls are knot-like swellings on the rootlets, and may lead to decay of infested parts. Root galls cause stunting and or death of European varieties of grape vines. American varieties of grapes, or European grapes on American root stock are tolerant to the root gall form of the insect. Some varieties are resistant are to root galls, leaf galls or both. The life cycle of grape phylloxera is complex due to the fact that generations with different life cycles may develop at the same time, at least in the eastern US. In spring, a female hatches from a fertilized egg that had been laid on the wood of a grape vine. She migrates to a leaf where she produces a gall and grows to maturity in about 15 days. She fills the gall with eggs and dies soon afterward. Nymphs that hatch from these eggs escape from the gall, and wander to new leaves where they in turn produce galls and eggs. There maybe 6 or 7 generations of this form during the summer. In the fall, nymphs migrate to the roots where they hibernate through the winter. The following spring they become active again and produce the root galls on susceptible varieties of grapes. These wingless females may cycle indefinitely on the roots year after year. In late summer and fall, in the eastern U.S., some of the root inhabiting phylloxera lay eggs that develop into winged females. These females migrate from the roots to the stems where they lay eggs of two sizes, the smaller ones developing into males and the larger ones into females. Mating occurs and the female then lays a single fertilized egg that over winters on the grape stem. It is this egg that gives rise to leaf inhabiting generations. Phylloxera cycle continuously as root inhabitants. Although They can cycle continuously on the roots without leaf forms occurring, leaf inhabiting forms do not occur without the root form also occurring. European varieties of grapes should be grafted onto American grape root stocks. Foliar sprays to control phylloxera during their wandering stage does not accomplish any useful purpose. Grape Rootworm Grape rootworm is distributed from the Mississippi River eastward. Larvae devour small roots and pit the surface of larger roots, causing an unthrifty condition of the plant, and reduction in yield. Vines may be killed in 3 or more years when damage is severe. Adults make chain-like feeding marks on leaves and may also feed on the surface of green grape berries. Hosts include wild and cultivated grapes. The adult beetle is elongate oval, sub cylindrical, dark reddish brown, clothed with short pubescence and is about 1/4 to 1/3 inch long. The larva is white, hairy, curved, with a brown head. Grubs in various stages of development pass the winter in soil at a depth of a few inches to 2 or more feet. In the spring, they migrate to within 1 or 2 inches of the soil surface, where they root feed for a while before forming a small earthen cell to pupate in late May and June. Adults emerge over a period of 4 to 6 weeks, beginning about 2 weeks after grapes bloom, and feed on leaf upper surfaces in a characteristic manner. Soon after feeding begins, females lay eggs in masses of 20 to 30 on canes, usually under loose bark. Eggs hatch in 1 to 2 weeks, larvae drop to the ground, and enter the soil where they feed until the approach of cold weather. There is one generation per year. Chain-like leaf feeding damage by the adults is diagnostic and can alert growers to adult activity. Foliar sprays when adults are active can provide effective control. Grape Flea Beetle Grape flea beetle is found in the eastern two-thirds of the United states. Adults eat buds and unfolding leaves, causing leaves to be ragged and tattered. Larvae feed on flower clusters and skeletonize leaves in a manner similar to adult rootworm feeding. Hosts include grape, plum, apple, quince, beech, elm & Virginia creeper. Adults are dark metallic greenish-blue, jumping beetles about 1/5 inch long; larvae are brownish and marked with black spots; eggs are pale yellow, and fairly conspicuous on upper leaf surface or under loose cane bark. Adults overwinter in protected areas around vineyards, and start feeding on interior of primary buds and opening grape leaves in early spring. Damaged buds will not develop into primary canes which can reduce yields. Once the buds are 1/2" long, only slight injury is caused. The females lay eggs under loose cane bark on vines, or occasionally on leaf upper surfaces, or on buds. The light yellow fairly conspicuous eggs hatch in a few days. The larvae feed on leaves for 3 to 4 weeks, then drop to the ground where they pupate in the soil, and emerge as adults in 1 to 2 weeks later. New adults feed for the remainder of the summer and go into hibernation in fall. There is only 1 generation per year. Damage is often restricted to vineyard borders, particularly near wooded areas. Scheduled sprays for grape berry moth and leafhoppers provide effective control. Where flea beetles have been a problem, a spray timed at bud swell can provide control. Grape Cane Girdler Grape cane girdler is common in central and eastern United States. Adults girdle canes with a row of punctures, that causes canes to break off at the girdled areas. It is only a minor pest on grape, preferring Virginia creeper. Hosts include grape and Virginia creeper. The adult is a black snout beetle about 1/8 inch long. The grub is slightly larger when full grown, and is white with brown head and legless. It is very similar in appearance to the closely related grape cane gall maker. Eggs are laid in late spring in a series of holes encircling the cane made with its mouthparts. After eggs are laid, the female continues to make another series of punctures a few inches below the first girdle until the cane is encircled, but eggs are placed only in the holes of the first girdle. A similar girdle is made at a point higher on the cane, causing the end to break. Grubs feed in the cane pith between the girdles. After larval development is completed, pupation occurs. Adults appear in late summer, go into hibernation, and reappear in late spring. Girdles are usually beyond the fruit clusters and do not cause significant yield loss. Look for broken off, pencil-sized canes with a grub in the pith of each broken off section, or wilted canes with a series of punctures. Pruning canes a few inches below the lower girdled area is usually sufficient control for this pest. Pruning should be done before adult emergence in late July or August. Grape Cane Gallmaker Grape cane gallmaker is a common pest of grapes in Kentucky. This insect produces noticeable red galls on new shoot growth just above nodes. While these are commonly found in vineyards, the majority of the galls are beyond the fruit clusters and usually cause no serious yield loss. Canes with galls are capable of producing a crop the following year. The adult is a dark brown snout beetle about 1/8 inch long and is very similar in appearance to the grape cane girdler. The grub is slightly larger when full grown, and is white with brown head and legless. In May and June, the female lays an egg in one of a series of holes she chews along the cane just above a node when canes are 10 to 20 inches long. The larva feeds inside the cane which has developed a reddish swelling 3/4 to 1 inch long. The larva becomes fully developed in late July and pupates within the galls. Adult beetles emerge during August and remain in or near the vineyard area, overwintering in trashy borders. Galls are usually found along vineyard borders near wooded trashy areas or at ends of rows. If galls will be removed by pruning, it should be done by mid-July before emerging adults exit galls. Grape Root Borer Grape root borer is potentially the most destructive insect attacking grapes in Kentucky. Larvae of this insect tunnel into larger roots and crown of vines below the soil surface. Borer damage results in reduced vine growth, smaller leaves, reduced berry size, and fewer bunches of grapes. Because damage is restricted below ground, problems often go unnoticed until vine decline is observed. Damage caused by larval feeding can range from just a few feeding sites to complete root system destruction. Adults are brown moths with thin yellow bands on the abdomen and resemble some paper wasps. The front wings are brown while hindwings are clear. Male moths fly about in a manner similar to wasps. Larvae are cylindrical, cream-colored, with three paris of true legs near the head and five pairs of fleshy abdominal prolegs each bearing two bands of tiny hooks. The larvae are 1-1/2 inch long when mature and have a retractable brown head. Adults emerge from the soil in mid summer. Eggs are laid on the soil surface, grape leaves, and weeds with eight days of adult emergence. Females lay an average of 350 eggs. Eggs hatch in about two weeks and larva immediately tunnel into the soil in search of grape roots. About 95% of the larvae die before reaching roots, but less than 1% die after finding grape roots. Larvae will feed on the roots for 2 years. During the summer of the second year, larvae will pupate near the soil surface. Injury by root borers is often most severe in low, poorly drained areas of the vineyard. In mid-summer, growers should examine around the bases of vines out to a distance of 18 inches for empty pupal skins of grape root borer. If pupal skins are found beneath 5% of the vines then an insecticide application is recommended next year underneath vines. It is best to apply the insecticide just as the adults are beginning to emerge, but the preharvest interval may make it necessary to spray after harvest. The insecticide should be applied as a course spray to a 15 square foot area surrounding the vine. Treat with an insecticide only if necessary, if grape root borer is not a problem, there is no reason to risk destroying the natural control processes and increasing production costs. Redbanded Leafroller Redbanded leafroller is an occasional pest of clusters and fruits, and its symptoms are very similar to grape berry moth. Larvae of this insect will feed on both foliage and clusters. Unlike grape berry moth larvae, redbanded leafroller larvae do not crawl into the berry but remain concealed in webbing on the cluster stem and feed on the stem as well as berries. While redbanded leafrollers are numerous in Kentucky, they are only an occasional pest of grapes. The adult redbanded leafroller is a 1/2 inch long reddish-brown moth with small areas of silver, gold and orange. The moth is recognized by the red band extending across the front wings when at rest. The larva is a small, yellowish-green, unmarked caterpillar. The head capsule is the same color as the rest of the body. The redbanded leafroller overwinters as pupae in leaf litter on the soil surface. Adults emerge in April and begin laying clusters of eggs on canes. Larvae of this early generation feed on unfolding leaves and are not usually of major concern. Larvae of the 2nd and 3rd generations feed during the summer and are of economic importance due to berry feeding. Second and third generations are larger than the first, and egg laying occurs over an extended period of time. Growers can control for redbanded leafrollers at petal fall or when presence of the pest is detected. Pheromone traps are available to monitor for redbanded leafroller. Trap catches are an indication of moth activity and can be used to more accurately time insecticide applications. General Management Guidelines There are a number of cultural control practices that grape growers need to use to reduce problems caused by insect pests. These cultural practices include: ? Burying or removing leaves under the vines during the winter. ? Summer pruning vines to remove grape cane gallmaker and grape cane girdler before adult emergence. ? Use american rootstocks resistant to grape phylloxera. ? Maintain good weed control during the season, and eliminate weedy or trashy harborages around the vineyard that serve as overwintering sites for pests. Use systematic scouting of vineyards to monitor for grape insects on a regular basis. Particular attention should be made to the ends of rows and rows borbering wooded areas. It is on these vines that insect problems may develop initially and with the greatest severity. During mid-summer, growers should examine around the bases of vines for evidence of grape root borer emergence. Growers should record and maintain notes of each visit to the vineyard. See ID-93, Kentucky Commercial Small Fruit & Grape Spray Guide, for a listing of the recommended insecticide sprays. REDNECKED AND RASPBERRY CANE BORERS by Ric Bessin, Extension Entomologist University of Kentucky College of Agriculture Adapted from: D. T. Johnson, Univ. of Arkansas Rednecked Cane Borer The rednecked cane borer can be a serious pest of raspberries and blackberries throughout Kentucky. Adult rednecked cane borers attack foliage, often feeding on the upper leaf surfaces during the day leaving irregular holes. Larvae feed on and girdle the primocanes which form irregular swellings or galls. Galls are between 1 to 3 inches in length and often split the bark. Most galls are found at ground level but they maybe as much as 4 ft above the ground. Infested canes die or become so weakened they can not support a crop the following season. Rednecked cane borers may infest as much as 50 percent of the canes in one or two years old plantings. Girdled canes are predisposed to winter injury. The rednecked cane borer adult is a small metallic wood-boring beetle. The slender adults are about 1 /4 inch long, they are all black except for a iridescent coppery-red to golden thorax or "neck". Larvae are white, legless and are flattened just behind the head. They are between 5/8 to 3/4 inch long when mature and have a pair of dark-brown, toothed, forceps-like prongs. Pupae are about the same length and shape as adults. The rednecked cane borers overwinter in canes as larvae. Larvae molt twice in the spring, then they excavate enlarged cavities in the cane. By mid to late May they shorten and pupate. Pupae molt to the adult stage by early-June. They remain in the cane for 10 or more days, during this time they mature and chew a "D"-shaped exit hole to allow emergence from the cane. Rednecked cane borer adults emerge from canes in early June to mid June. They feed on the young primocane foliage for several days before laying eggs. Eggs are cemented to the cane, and hatch in four to 24 days, depending on temperature. Larvae chew into the cane and tunnel in a spiral fashion around the cane. Larvae normally tunnel upward into the pith, but tunnels may extend 6 inches below to 25 inches above the gall. When looking for overwintering larvae it is best to split the cane at the gall and follow the brown, discolored tunnel from the gall to its end. Live larvae are rarely found in the gall. Observations on natural control of rednecked cane borer are mixed. However, research conducted in other states have reported as high as 75 percent natural mortality of rednecked cane borers in canes due to fungal diseases, parasitic wasps and unknown causes. During winter pruning, growers need to determine the presence and extent of rednecked cane borer damage. If more than 10 percent of the primocanes are galled or the number of galled primocanes is greater than the number of canes you expect to prune out, control of this insect is advisable. Growers are encouraged to prune out galled canes and burn them before bud swell. Nearby sources of infestation should also be removed and burned during this dormant period. If parasitism is high it may be wise to leave pruned out cane in the planting to enhance the level of parasitism. If parasitism is low pruning and burning is probably better. If heavy rednecked cane borer infestations are not controlled by pruning and burning of galled canes, insecticidal control is suggested. Two insecticide applications, 7 to 12 days apart, timed to coincide with adult emergence, June through early July, will provide helpful control. Do not spray until adult emergence has been observed in your area. Raspberry Cane Borer Attack by the raspberry cane borer to blackberry, raspberry and rose resulting in tip die back and cane death. Damage is readily identified with this insect by two rings of punctures about 1/2 inch apart and located 4-6 inch below the growing tip. These girdles cause the tip to wilt. Damage becomes more profound as the larva burrows to the base of the cane, causing the entire cane to die before the fruit matures. The raspberry cane borer is a slender long-horned beetle measuring about 1 /2 inch long. It is black in color except for a yellow-orange thorax with two or three black dots and long antennae. The elongate, cylindrical, legless larva is white and attains a length of nearly 3/4 inch. Raspberry cane borer adults appear about June and after puncturing the two rings in the canes, lay an egg between the rings. These hatch in July and the larva begins burrowing towards the base of the cane and overwinters about 2 inch below the girdling. The second season it continues to burrow downwards to ground level where it spends the winter. It emerges as an adult the following spring. The planting should be examined weekly during June and July. The existence of wilting tips characterized by the two rings described earlier identify attack by raspberry cane borer. Control is obtained by pruning out the infested canes by cutting a few inches below the oviposition rings or below the larval tunnel. PECAN INSECTS Including those attacking shellbark and shagbark hickories by Ric Bessin, Extension Entomologist University of Kentucky College of Agriculture Leaf Feeders Aphids Aphids are soft-bodied, sucking insects that appear in the summer and fall. Usually serious numbers do not develop until the late summer. There are two species involved, the black pecan aphid (greenish black) and the yellow aphid. Damage consists of sap removal which causes leaves to turn yellow or brown and fall. Heavy infestations may reduce the nut crop the current year and/or the following year. Aphids are considered secondary pests and often buildup following thw use of pesticide sprays The black pecan aphid prefers the shady, inner parts of the tree, and is typically a late season pest. The first sign of leaflet injury is bright yellow areas where the insects have fed. These areas later turn brown and leaves drop due to the toxin injected into the leaf. Yellow aphid infestations often result in growth of sooty mold due to honeydew secretions. Organophosphate insecticides appear more effective against black aphids. The economic threshold for black aphids is an average of one aphid or damaged area per compound leaf. The threshold for yellow aphids is 10 per compound leaf. No more than 2 pyrethroid applications should be used in order to prevent development of resistance by aphids. A winter cover crop of crimson clover or hairy vetch within the orchard is beneficial. In the early spring, beneficial insects can build up in numbers by feeding on pea aphids and other insects found on these cover crops. Aphids over winter as eggs laid in bark crevices on the tree. Aphids emerge in the spring and soon begin to reproduce asexually. Many generations occur each year. Mites Feeding with sucking mouth parts, mites remove the cell contents of leaves. These tiny pests usually attack the undersides of the leaves, typically around the midrib, causing irregular brown areas. These scorched areas begin at the midrib and spread outward. Heavily infested trees may lose their leaves or appear scorched. Use of Sevin or pyrethroid insecticides may lead to mite outbreaks. Mites are light green in color and just large enough to see without a hand lens. Often tapping an infested leaf over a white sheet of paper will aid in identification. Mite colonies produce webs in which cast-skins and eggs may be found. The life cycle is short, and many generations occur each year. Pecan Phylloxera This aphid-like pest produces galls on new pecan growth. Leaves, twigs and nuts may be affected. Phylloxera over winter as eggs in bark crevices. In the spring eggs hatch and the tiny nymphs feed on tender young growth, secreting a substance which stimulates plant tissues to develop into galls. When the nymph matures, eggs are deposited in the gall. Young nymphs develop within the gall. The gall splits in several weeks liberating them.Several generations are produced each year, as long as there is fresh young growth on the tree. Control is initiated with the use of a dormant oil application. During the growing season, controls should target the "crawler" stage before the galls form. Once the gall is formed the damage is done. The crawler is active just before or at bud-break. Controls initiated after the start of gall formation are not effective. Trunk and Twig Feeders Shot-hole borer Shot-hole borers tend to attack devitalized trees. Larvae feed in the wood and emerge as adults through small round holes in the bark (1/8 inch). Since this insect feeds on dead or dying wood, remove prunings and dead limbs from the orchard and burn them. Adequate fertilizer and water will keep the trees healthy and prevent infestation by this pest. Twig girdler The adult twig girdler girdles twigs and small branches, such that they are weakened and fall off the tree. The insect is active late in the summer and fall. Secondary branching may occur around these sites and the number of bearing twigs reduced. This insect is particularly common near timberland containing hickory or persimmon. The twig girdler is a grayish brown beetle, 1/2 to 5/8 inch long, with a broad gray band over the wing covers. Its head is reddish brown and bears a pair of long antennae, which extend beyond the abdomen on the male. The larva is a white legless grub about 3/4 inch when mature. The insect overwinters as a partially grown larva in a twig either in the tree or on the ground. It develops rapidly in the spring, feeding on the dead wood in the twig. Following pupation, the adult emerges in August or September. The female girdles the twig and deposits her eggs in the severed portion, the larva is unable to develop on healthy wood. Eggs hatch and larvae feed, but remain small until the following spring. Infestations may be reduced by removing girdled twigs in the fall and winter and burning them. Girdled twigs from surrounding hickory and persimmon trees need to be destroyed as well. Flat-headed Apple Tree Borers Flat-headed apple tree borers attack primarily unhealthy or newly transplanted pecan trees by burrowing into the bark and sap wood of large branches and the trunk. Often darkened depressed areas with traces of frass are evidence of their activity. Beneath these areas, shallow galleries packed with sawdust may be observed. Burrows are usually on the sunny side of the trunk or branch, but this insect may girdle young trees (often less than 2" in diameter). The insect is about 1/2 inch with a blunt head and tapering abdomen. The body is metallic dark green, corrugated, and flattened. The larva is creamy white, legless, and flattened and broadened immediately behind the head. This insect overwinters as a larva in the tree. Adults emerge in the spring or summer. Females lay eggs in bark cracks and injuries. There is one generation per year. These insects are attracted to trees in a devitalized condition induced by transplanting shock, drought, sun scald, wounds, or poor growing conditions. Keep trees well watered and moderately fertilized. Young or transplanted trees should be wrapped from ground level to the branches with burlap or heavy paper. Tie wrapping material with twine and leave in place for two years. Make sure the twine does not girdle the tree. Remove dead and dying limbs and trees from the orchard each year and burn them before the following spring. If practical, remove borers from infested trees with a thin wire. Nut Feeders Shuckworm Can be one of the more destructive pests of pecan. These are white worms that grow to 3/8 inch and tunnel in small nuts causing them to drop in July and August. After shells harden, larvae tunnel in shucks and prevent kernels from developing properly. This can delay nut maturity. Shuckworm can stain the nuts and cause part of the husks to adhere to the shells. There can be two generations. Shuckworms over winter as full grown larvae in shucks on the ground or on the tree. They pupate within the shuck in late winter. Growers not equipped to spray should gather and destroy the shucks at harvest. The drops(small nuts) should be gathered and destroyed during midsummer. If the orchard is cultivated, you can reduce damage by covering the shed nuts with soil in July and August. A disk set to turn soil to a depth of three inches will cover most of the nuts and cause them to decay before larvae complete development. Stink bugs and plant bugs These sucking insects feed on the developing kernels and cause an injury known as black pit. Injured nuts may fall from the tree prior to maturity. Feeding occurring after the shells have hardened results in brown or black spots on the kernels that taste bitter. These insects over winter as adults in ground litter and weeds. While adults can frequently be found on trees while nuts are developing, nymphs do not develop on pecan trees. Nymphs develop on weeds. To control these insects, weeds should be kept down during the growing season. Winter cover crops should be mowed early, before these insects come out of hibernation. ROSY APPLE APHIDS by Ric Bessin, Extension Entomologist University of Kentucky College of Agriculture Generally three species of aphids - the green apple aphid, rosy apple aphid, and apple-grain aphid - attack apple foliage in Kentucky. However, it is the rosy apple aphid which cause the most severe damage and is the most difficult of the three to control. While large number of any type of aphid can stunt new growth and cause sooty mold to develop on fruit and leaves, the rosy apple aphid injects a toxin with its saliva that causes the leaf to curl and the fruit to be distorted. Often these damaged leaves turn bright crimson in color. Relatively low numbers of rosy apple aphids can cause considerable damage. While all apple varieties are attacked attacked by rosy apple aphid, 'Cortland', 'Ida Red', and 'Golden Delicious' are particularly susceptible. Feeding on the leaves of fruit clusters often results in stunting and malformation of the fruit. For this reason, rosy apple aphids are the most serious aphids attacking apples. Honeydew produced by the aphids promotes the growth of sooty mold as well. This becomes more noticeable as the fruit develops. Problems usually begin to appear after petal fall and by mid summer the aphids move to alternate hosts. The aphid overwinters on apple trees as eggs laid on twigs, bud axils, or in bark crevices. The black eggs are 1/2 mm long and football shaped. Shortly after silver tip the eggs hatch. The nymphs color changes from dark green to purple as they grow. The overwintering eggs give rise to only females aphids which give birth to live young. The aphids continue to reproduce on apple until summer, then winged forms are produced which migrate to other hosts such as dock and narrow-leaved plantain to spend the summer. In the late fall, winged forms migrate back to apples and lay eggs in bark crevices and on twigs. Apple growers should monitor their trees carefully for rosy apple aphids, a few colonies can rapidly infest the entire tree. Because these infestations will curl the leaves, early control is important. Once the leaves are tightly curled, adequate spray coverage and control is more difficult. There are a number of predators that often control rosy apple aphid, so distorted leaves should be open to determine if the aphids or predators are still present before making control decisions. Rosy apple infestations often go unnoticed until the leaf curl damage is observed. Because control becomes extremely difficult once the leaves are tightly curled, rosy apple aphids are best controlled at the pink stage of bud development, before the serious leaf curl has occurred. Management Options Delayed Dormant Oil The green apple aphid, apple-grain aphid and rosy apple aphid overwinter as eggs on twigs and bark crevices of apple trees. A delated dormant oil application between green-tip and half-inch green controls newly hatched aphids. Failure to use a properly timed delayed dormant oil application may require additional inseason treatments. These inseason treatments are usually more expensive and disrupt beneficial insects that control secondary pests. Monitoring and Economic Thresholds Examine four leaf terminals on each of 5 scaffold limbs on each tree for active aphid colonies. Record the total number of aphid infestations per 20 leaf terminals or fruit clusters by species. If a leaf terminal has ANY live aphids on any of the leaves, it is considered infested. Treatments are recommended when 5% of the terminals are found to have rosy apple aphid infestations. Other aphids such as the green apple aphid and the apple grain aphid do not curl leaves and have higher action thresholds of 50% infested terminals. Effective control of rosy apple aphid can only occur prior to leaf curl. Trees need to be examined for rosy apple aphids at the pink stage of development. Diazinon or malathion can provide effective control of these pests when they exceed threholds. Insecticidal Soap and Summer Horticultural Oil A 1 to 2 % application of insecticidal soap or summer horticultural oil can provide effective control of these aphids. Use the monitoring and economic thresholds and apply these as necessary. Neither of these will provide any residual control, so thorough coverage is essential. Control of rosy apple aphid after the leaves have curled may be difficult. While effective control can be obtained with a 1 to 2% summer horticultural oil treatments, caution is advised as these may be incompatible with some other pesticides (particularly sulfur containing products), are phytotoxic at higher temperatures (above 100øF and high humidity) and at high concentrations (> 2%), and may affect fruit finish on some varieties. ORIENTAL FRUIT MOTH by Ric Bessin, Extension Entomologist University of Kentucky College of Agriculture The oriental fruit moth is one of the most serious pests of peaches in Kentucky. Early in the season, this insect damages succulent terminal growth and attacks fruit in mid summer. Although there can be four to five generations each year, the second and third generations which cause most of the damage. In addition to peaches, this insect attacks apple, plum, cherry, pear, and rose. The oriental fruit moth is a small (1/4 inch), charcoal-colored, nondescript moth. Fine alternating bands of light and dark lines on the wings give it a mottled appearance. The small, flat, oval eggs that are laid individually or in small clusters on the foliage primarily, usually on the upper leaf surfaces of the terminal growth. The larva pinkish white with a brwon head and is 1/2 inch long when full grown. The larvae pupate in a silk cocoon in crevices in the bark or in litter at the base of the tree. The oriental fruit moth overwinters as a full-grown larva in a cocoon in protected places on the trunk or around the base of the tree. They pupate beginning in late March and moth emergence usually coincides with peach bloom. First generation larvae tunnel into the young, tender, terminal growth near the base of a leaf early in the season. The larvae may tunnel down the center of the twig for 2 to 6 inches before completing development or exiting and moving to another shoot. Successive leaves begin to wilt as the larva progresses down the twig. This injury causes dieback or flagging of these twigs. Larvae often damage 2 or 3 twigs before reaching maturity. These larvae can complete their development in less than a month. Larvae of subsequent generations feed on fruit, when available, and twigs. As the twigs harden, the partially grown larvae leave them and enter the fruits to feed. Larvae commonly bore right to the center of the fruit and feed around the pit. Larvae feeding on the fruit often causes it to drop. These wounds serve as sites for development of rots. Young fruit often exude gum from the entrance and exit holes left by the larvae. Damaged fruit that remain on the tree are distorted. Occasionally, the larva may tunnel into the fruit through the stem. In such instances there may not be any apparent evidence of how the larvae entered the fruit after it was harvested. Management Pheromone traps are available for this insect to monitor moth activity and effectively time sprays. Traps are placed in the inside of the tree at eye level or higher just before bloom. One trap per ten acres is recommended for commercial orchards, with a minimum of two traps. For backyard trees a single trap can be used and an insecticide treatment is made at petal fall if the insect is detected. Commercially, sprays for the first generation should be applied 6 days after peak flight which coincides with peak egg laying. This often coincides with the time for plum curculio control. Sprays for the second and third generations need to be applied 3 days after peak flight. Depending on the anticipated harvest date for the fruit, sprays for the third generation may need to be adjusted or omitted in order to meet the necessary preharvest intervals (PHI) requirements for certain insecticides. Some producers in Michigan and on the West Coast have successfully adopted mating disruption strategies for oriental fruit moth management in peaches. With mating disruption, pheromone (sex attractant) dispensers are placed throughout the orchard. As the pheromone is released from the dispensers, male moths that normally use the pheromones to locate females become confused. This interferes with the mating process. Approximately 400 of the twist-tie dispensers are used per acre and are placed in the mid to upper level of the tree canopy. Pheromone traps are used to evaluate the effectiveness of the mating disruption. If mating disruption is working, the pheromone traps should catch no moths. Mating disruption is only recommended for orchard of 5 acres or larger in size. Examine trees regularly in the early spring for signs of wilted shoots. Examine wilted shoots carefully to determine if oriental fruit moth was the cause of the injury. Young trees with vigorous new growth are often very susceptible to injury by this insect. Oriental fruit moth prefers to feed in the tops of trees. Detection of early season shoot damage indicates the potential for fruit damage by later generations. $