WHEAT
Hessian Fly - See:
http://everest.ento.vt.edu/Facilities/OnCampus/IDLab/HessianFly/hessian.html
This fly is not so much of a major pest but still shows up in my lab. Look for patchy poorly developing wheat fields. At this time of year you will find the small "flax seed" pupa at the base of the plant under the leaf sheath. Two practices that reduce its presence should be continued and they are planting in mid to late October after most of the adult egg laying flies have died off and to remove any volunteer wheat found in or near where wheat is to be planted that season.
Thrips - Thrips are very common in Virginia this spring again. Any puckering, stunting, leaf curl, or stippling on shade trees and some crops may be caused by damaging populations of thrips. Check for the thrips by looking in the buds or flowers for lemon yellow insects about 1/8" long.
Woolly Fold Gall - This gall is common on oak in Virginia. It causes the leaves to pucker and curl along the mid-rib of the leaf. As the name implies the gall is also woolly on the inside and small maggots may be found inside at this time of year. Rarely does this gall cause damage but if most of the leaves are injured then the trees growth may be stunted: in this case treat under the tree with a white grub treatment as this particular gall overwinters in the soil.
Boxelder Bugs - These bugs are starting to feed on female Boxelder (seed producing) trees. Boxelder bugs will not harm the tree but can be household pests in the fall when they seek overwintering sites.
Soft Scales - Many soft scales including Calico Scale, Cottony Maple Scale, Cottony Camellia Scale, and Lecanium Scales have crawler dates in June and control should be planned for June 10 + 20.
Boxwood Leafminer - Boxwoods infested with leafminers will need to be treated in Mid-June with a systemic insecticide.
Onion Thrips - Onions with damage similar to spider mites are probably damaged instead by Onion Thrips. Like the spider mite the thrips will leave white stippling although the spots are slightly larger. The small lemon yellow thrips will be found nearby. Both Malathion and Diazinon are labeled for onion and will work well on this critter.
Many, many calls on wood boring bees. Carpenter bees are large
bees, resembling bumble bees. They are heavy-bodied and metallic
blue-black with green or purplish highlights. The bodies are covered
with bright yellow or orange hairs.
HABITAT: These insects build their nests in wood siding, the ends of
logs used in modern log houses, or other areas where bare or painted
wood is exposed.
LIFE CYCLE: The males and females cut a one-half inch circular hole
into the wood, then create a tunnel parallel to the surface of the
wood. Within the tunnel the female stores food and lays eggs. The
developing carpenter bee larvae are in individual cells in the
tunnel. There is usually only one generation per year.
TYPE OF DAMAGE: Cut holes in wood; yellow sawdust containing waste
materials leaves unsightly stains.
CONTROL: Control of these insects can be achieved by spraying the
entrance hole with an aerosol insecticide. Existing holes can be
plugged with a moth ball to prevent adults from returning or the
second generation adults from emerging.
INTERESTING FACTS: Females are quite docile, although they can sting.
Males are aggressive, but cannot sting.
Insects to be on the Lookout for in June Eric Day Manager, Insect Identification Laboratory Insect:Host(s) Description Treatment timing* FIELD AND VEGETABLE CROPS Aphids: Look for small soft- Cut out and destroy small Any crop but in bodied insects causing localized areas on plants or particular cru- the leaves to be stunted, treat with an insecticide cifer crops yellowed, and/or curled. labeled for aphids and that particular crop. Black Cutworm Medium to large cater- If more than 5% of the plants and other pillars cut off plants at are cut then control with an Cutworms: the base. Inspect newly insecticide or bait is Many crops but planted seed beds and newly warranted. in particular set plants. corn Colorado Potato Adults are yellow with For small gardens, beetles Beetle: brown stripes, they are can be removed by hand- Potato, tomato, oval-convex in shape. The picking, larger areas or eggplant,pepper, larva is yellowish red or heavy infestations will tobacco, and orange and has a row of require the use of insect- other solan- black spots along each side icides. aceous plants of its body. Cucumber Beetle: Two beetles feed on cucur- Foliar sprays may Cucumber, can- bits in Virginia, the spot- be necessary in some taloupes, gourd, ted cuc. beetle is pale cases. To prevent bac- squash, and green with black spots on terial wilt treat when 1 watermelon are its wing covers, the striped beetle per 100 row feet preferred hosts. cuc. beetle is pale green is found. They are found with black stripes on its on other crops wing covers. Both transmit but are not as bacterial wilt of cucurbits. important. European Corn On corn look for shot-hole Treatment on field corn is Borer: Many damage in the whorl late- warranted if more than 50% crops but in June and early-July. In of the plants have an egg particular corn addition, look for the flat- mass. Count 50 random plants tened egg masses with eggs and if the average overlapping like fish scales on number of egg mass on the undersides of the exceeds 0.5 then treatment leaves, look from the first may be necessary. Treatment of July to mid July for the must be made just after egg egg masses. Be sure to scout hatch. Growers in Virginia the inner parts of the field usually treat between the because the border rows first and fifteenth of July tend to have higher pop- when necessary. ulations of ECB. Flea beetle: Small black beetles jump- Spray with Sevin when damage Corn, eggplant, ing like fleas when dis- becomes severe. and many other turbed from the leaves of crops a plant. They scrape the upper epidermis layer off the leaf and sometimes fruit leaving a brown scar. Imported Velvet green caterpillars Treat when caterpillar Cabbageworm: with a faint yellow stripe populations reach a Cabbage, broc- down the back and a row of threshold of one worm coli, cauli- yellow spots on each side. per plant, repeat every flower, and Medium sized. 5 to 7 days as needed. other crucifers True Armyworm: Medium to large cater- When defoliation reaches Corn and other pillars, brown with 20%, insecticide control grass plants, yellow markings, usually is warranted. but on many veg- feeding on the upper parts etable crops as of the plant at night. well Stink Bug: Barrel shaped eggs are Removing weedy growth that Many crops but laid on the undersides of harbors stink bugs will cut in particular leaves, nymphs are black down on native breeding pepper and and white or red or green. sites. Spot treatments of tomato Adults are green or tan. insecticides when stink All stages have piercing- bugs are seen is recom- sucking mouth parts. mended. Damage to pepper and tomato appears as white halos and deformations on the fruits. Squash Bug: Nymphs are grayish white Handpicking works well All cucurbits; with dark heads and appen- in small gardens. Chem- squash bugs pre- dages. Adults are oval ical control might be fer squash, elongate, light gray, and needed in larger pumpkin, cucum- mottled yellow on the operations. ber, and melon underside. Nymphs tend in that order to be found on the basal portions of the vine. FRUIT INSECTS Codling Moth: Pinkish-white caterpillars If using pheromone traps, Apple and pear enter fruit at calyx end treat if you exceed 5/trap/ primarily, but and tunnel all the way week. cherries,peaches, to the core. Adult moths plums, apricots, are grayish-brown with and similar irregular golden brown fruits are lines on the fore wings. attacked. 1/2-3/4" wingspan. European Red Mites are very small and This mite is resistant to Mite: Apple range from red to green. many miticides, so make sure pear, plum, Foliage turns a sickly that the chemical you will prune, and bronze color as if covered use is effective. A dormant many other with dust. oil applied at the 1/2" trees and shrubs green leaf stage or earlier in the spring is important also. Green Apple Pale green nymphs on the Treat when 50% or more of Aphid: underside of leaves and the shoots are infested. Apple, pear new shoots, often a problem on trees with excessive shoot growth due to overfertilization. Peach Tree Look for a mass of gum Adults emerge July- Borer: Peach, and frass at the base of September; treat during plum, cherry, the trunk, white larvae the first week of July. nectarine, will be found under the apricot bark from 3" below the soil level to 10" above. San Jose Scale: Scales are dirty gray Treat June 10-15, Apple, pear, with a dark concentric late-July. cherry, and many ring on the center. other fruit trees Scales infest the bran- ches, twigs, and fruit. Variegated Leaf- Eggs are laid on leaves Treat when egg masses are roller and in masses in which the about to hatch (dark head Tufted Apple eggs overlap much like stage). Budworm: fish scales. Both are general feeders but are pests on apple and peach ORNAMENTAL INSECTS Azalea Bark Look for white cottony Treat June 10 and 20. Scale: Azalea, sacs covering dark red blueberry, females and eggs on the rhododendron forks of branches and twigs. Azalea Stem Look for tips dying back Treat mid-May and mid- Borer: Azalea, and yellow legless grubs June with an insect- rhododendron, up to 1/2" long boring icide or cut out and mountain-laurel, in twigs and trunk. destroy dead and dying blueberry tips as noticed. Borer paste in the holes will give some control also. Bagworm: Caterpillars form "bags" Pick off and destroy all Conifers, maples around their bodies made of bagworms now and/or treat sycamores, box- silk and plant debris. with an insecticide in mid- elder, and many They overwinter as eggs June. Next spring, early, others in the bags; the eggs pick off all bags you can hatch in late May and find. early June. Black Vine Adults notch leaves inward Treat with an insecticide Weevil: Nearly from the outer margin. in the second or third week 80 hosts inclu- Larvae feed on the roots of June. Spray the leaves ding most broad- and weaken the plant, branches, trunk, and soil leaved evergreens often causing it to wilt. under the plant. Bronze Birch Look for the top of the Treat mid-May, and Borer: Birch, tree dying back and up to early-, mid-, and cottonwood, 1" long flat-headed borers late-June; spray trunk poplar, aspen under the bark. and branches heavily and leaves lightly. Boxwood Leaf- Look for yellowed Treat early June; the miner: Boxwood leaves and leaves with addition of a wetting agent small brown spots. This may be helpful. time of year the adult yellow flies may still be found on the foliage. Cottony Maple Look for cottony masses Treat June 10 and 20. Scale: on the undersides of twigs All maples, and branches. Foliage on locust, white affected branches may turn ash, red mul- yellow and the branch may berry, linden die. boxwood and many others Cottony Camellia Look for a long fluted Treat June 10-20. Scale: yew (taxus), cottony egg mass on the camellia, holly undersides of leaves and branches. Eastern Pine Look for yellow loopers Treat if damaging numbers Looper: pitch with black markings are found. red, shortleaf, feeding on the foliage. and loblolly Usually a minor pest, but pine because large numbers of the adult moths were seen this spring it may present a problem on some plantings. Elm Leaf Newly hatched larvae are Control newly hatched Beetles: Elm yellowish with black larvae in late-May markings; adults are olive and early-June. green with two black lines. European Fruit Large hemispherical to Treat June 10-15. Lecanium Scale: oval scale, shiny brown or Most fruit trees reddish-brown but some- and many orna- time covered with a white mental plants. powder. On the bark and twigs in the winter and on the leaves near the mid- rib during the summer. Fall Webworm: Eggs are laid in a mass Nests can be pruned out in Most fruit and of 200 to 500 often cover- early summer or if a large nut trees as ed with a woolly layer of number of nests exists, well as some scales. Large groups of treat mid- to late-June hardwoods and larvae form a nest at the or when new larvae appear. shrubs. tip of a branch. Florinia Hemlock Cast skins give trees a Treat May 20-25 and Scale: Hemlock white-washed appearance June 5-10 fir, spruce, yew with many scales on the undersides of needles. Scales under close exam- ination are yellow in color. Crawler stage peaks May 15-June 20. Gloomy Scale: Dark gray and circular Treat June 20-30. Mostly soft scales, blending in Note this scale is maples closely with the color often controlled by of the bark. its natural enemies. Hickory Leaf Galls shaped like No control is needed on Stem Gall: bullets develop on the large trees as these galls Hickory petioles and shoots. do not harm them. On small Leaves with galls fall trees or nursery stock off the tree prematurely control may be warranted causing concern by the tree's owner. Galls are formed by aphids. Holly Leafminer: Look for long serpentine Treat mid-June with a Native and or blotch mines in the systemic insecticide. English holly leaves. Heavily infested Small numbers of infested leaves turn yellow-brown. leaves can be picked off Inside the leaves will and destroyed. be small pale larvae. Juniper Scale: Crawler stage is from Treat April 10-15 Juniper April 5-22 and June and/or June 10-15. 5-20. Scales have an elongate white covering with a yellow cap at one end. Japanese Scale: Long and narrow scale, Treat at 2-week intervals Maple, privet dull white in color, from June 1-Sept. 1. often found on the trunks and branches. Japanese Weevil: Cuts broad notches on the Treat the second and Many ornamental outer margins of leaves. third weeks of June. plantings as well as garden plants Lace Bugs: New damage will not be Lace bugs overwinter as andromeda, oak apparent yet this year, adults on deciduous plants. azalea, walnut but last season's damage Treat in late May and repeat rhododendron, appears as stippling in June and July. On ever- sycamore and brown droppings on greens lace bugs overwinter the leaves. in the egg stage. Lecanium Scale: Scales are dark to light Treat June 15-20. Oak brown and elliptical in shape, often tapering at both ends. Mimosa Webworm: Larvae feed gregariously Treat when trees show Mimosa and in a web spun over the first signs of feeding in honeylocust flowers and leaves and June. May need to repeat in later feed individually mid-July and mid-August. on leaves and pods. Pine Bark Aphid: Look for cottony masses Treat late-June and Principally on on the bark and branches mid-August. Make sure the white pine but covering small, aphid-like, insecticide is applied with on other pines pale-green insects. strong stream that as well penetrates the "cotton". Small populations can be dislodged with a strong stream of water alone. Rhododendron Larvae bore in the sap- Treat June 10-15, and Borer: Rhodo- wood just under the bark, July 5-10. Prune out any dendron, some- causing the branches to infested branches. times azalea and wilt and die. Adults are mountain-laurel clear-winged moths. San Jose Scale: Scales are dirty gray Treat June 10-15, July Many trees and with a dark concentric 10-15, and September 10-15. and shrubs ring on the center. Scales infest the bran- ches, twigs, and fruit. Wax Scale: A globular off-white Treat June 10-30. Holly, euonymus, scale found on the twigs pyracantha, box- and leaves. So named wood, hemlock, because of its waxy cover. and others White Pine The larvae is a yellowish, Prune and destroy Weevil: Pines legless, grub that feeds infested shoots in and spruces under the bark on the May and June. terminal leader. The leader wilts and droops in the spring, indicating the presence of the grub.
* See Virginia Pest Management Guides for recommendations on insecticides and rates. Use insecticide applications only when high population levels demand control action. Most plants can support small populations of pest insects.
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