A. Damage by codling moth. WHITNEY CRANSHAW
INSECTS AND MITES ASSOCIATED WITH FLOWERS, FRUITS, NUTS, AND SEEDS
CODLING MOTH (Cydia pomonella)1
HOSTS Primarily apple and pear. Occasionally large-fruited crabapple, apricot, quince, hawthorn, and peach. Often infests developing walnut husks.
DAMAGE Larvae tunnel into the fruit of apple, pear, and crabapple. Less commonly they also damage other fruits. Codling moth is the single most important insect pest of tree fruits in North America.
DISTRIBUTION Throughout North America, common
APPEARANCE Larvae are pale tan, gray, or pink with a dark head and are found associated with the fruit. Adults are small (½ inch long) gray moths with coppery tipped forewings.
LIFE HISTORY AND HABITS Codling moth larvae spend the winter inside a silken cocoon attached to rough bark or other protected locations around a tree. With warm spring weather they pupate, and the adult moths later begin to emerge around blossom time. The spring appearance of this stage may occur primarily over the course of 1 or 2 weeks but can be much more prolonged if weather is cool.
During periods when early evening temperatures are warm (above 60° F) and not windy, the moths lay small white eggs on leaves. The larvae hatching from the eggs may feed first on the leaves but then migrate to the fruit, usually entering the calyx (flower) end. They tunnel the fruit, feeding primarily on the developing seeds. After about 3–4 weeks, the larvae become full grown, leave the fruit, and crawl or drop down from the tree to spin a cocoon and pupate.
After about 2 weeks, most—but not all—of the second generation of moths emerge from the pupae. The remaining pupae stay dormant, emerging the following season. (For example, in western Colorado only about two-thirds of the larvae go on to produce a second generation, and fewer than half of their progeny go on to produce a third generation.) Summer moths lay eggs directly on the fruit, and damage by the larvae to fruit is greatest at this time. When full grown, the larvae emerge from the fruit and seek protected areas in which to pupate.
RELATED SPECIES
Larvae of the HICKORY SHUCKWORM (Cydia caryana) develop within the shuck surrounding developing nuts of pecan and hickory, and this insect is considered one of the most destructive pests of pecans in the U.S. Presently hickory shuckworm is found throughout eastern North America in association with its host, but its range has extended westward into New Mexico.
The overwintering stage is a late-instar larva in the old shucks of fallen nuts. Pupation occurs in late winter or early spring and first generation adults begin to emerge in early May. Most egg laying by this first generation will occur on hickory, if available, which produces nuts of suitable size at this time. Eggs may be laid on leaves of pecan during the first generation, but nuts are not suitable for development and few larvae survive; most of those that are successful sustain themselves feeding in and around the galls produced by pecan phylloxera (page 324). Larvae produced in the second, early summer generation feed on the interior of pecans, causing damaged nuts to drop. Moths of the third generation usually appear in August and lay eggs on maturing nuts. At this point in time, pecan shells have hardened and hickory shuckworm caterpillars tunnel through the green shucks. Feeding injuries they produce include delayed maturity and incomplete kernel development.
B. External symptoms of codling moth damage to apple. WHITNEY CRANSHAW
C. Codling moth larva feeding in core. WHITNEY CRANSHAW
D. Codling moth pupa. WHITNEY CRANSHAW
E. Codling moth eggs on fruit. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
F. Adult codling moth. WHITNEY CRANSHAW
G. Entry hole produced by codling moth larva. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
H. Hickory shuckworm larva and damage. LOUIS TEDDERS, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
I. Adult hickory shuckworm pupa. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
J. Adult hickory shuckworm. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
FILBERTWORM (Cydia latiferreana) is associated with almost all cultivated and wild nuts grown in North America and is particularly common in oak acorns and hazelnut. Winter is spent as a full-grown larva in a cocoon on or in the vicinity of the previously infested host. Pupation occurs in spring, and adults are present over an extended period from late June into October. Eggs are usually laid on leaves, but the larvae migrate to nuts and develop in them. Larval development usually takes less than 1 month, after which the larvae exit to search for a protected site, where they spin a cocoon. One generation per year is normal, but egg laying continues over a period of several weeks.
PEA MOTH (Cydia nigricana) is primarily a pest of dried pea in the northwestern states. Occasionally it also damages green peas where large numbers of dried peas are grown nearby. The overwintering caterpillars pupate in spring, and the adults are present about the time peas flower in later spring. Eggs are laid singly near the flowers, and the caterpillar immediately bores into the developing pods. Larvae feed on the developing seeds and may injure several pods, often leaving little external evidence of infestation. When full grown they move to the soil and form a shelter in which they spend the winter. One generation per year is normal in much of the range, but two may occur in more southern areas.
ORIENTAL FRUIT MOTH (Grapholita molesta)1
HOSTS Peach, apricot, and nectarine are most seriously damaged, but plum, cherry, apple, pear, almond, and rose are other hosts.
DAMAGE Larval tunneling into twigs causes wilting terminals (“shoot strikes”), and two or three such injuries may be produced by an individual insect. Fruit is damaged as larvae feed randomly through the flesh, not consuming the seeds in the manner of codling moth. Fruit injuries also differ in that entry holes produced by Oriental fruit moth are often inconspicuous.
DISTRIBUTION An introduced species that is widespread in orchards in the eastern and southern U.S. It has spread to California and also occurs in isolated area of many western states.
APPEARANCE Adults are small grayish moths, about ⅖ inch, that fly just after sunset. Larvae are pink with a brown head, very similar in appearance to codling moth larvae.
LIFE HISTORY AND HABITS Winter is spent as a mature larva in a cocoon on or around a previously infested tree. Adults begin to emerge about the time peach blossom buds begin to show pink, and flights from this first generation may extend for almost 2 months. Eggs are laid on newly emerged shoots, and larvae feed in twigs. A second generation occurs in late spring (California) or early summer (Michigan) and attacks both twigs and fruit. Fruit injuries also occur when larvae move from twigs that harden and become unsuitable. A third generation occurs as peaches begin to mature, and most fruit infestations occur at this time. A small fourth generation is sometimes produced in Michigan and Ohio; five generations per year are normally produced in California.
RELATED SPECIES
CHERRY FRUITWORM (Grapholita packardi) damages blueberry, tart cherry, apple, and peach throughout the northern two-thirds of the U.S. and Canada. Hawthorn and rose are other hosts. Larvae develop in fruit, and individuals may damage several small fruits before becoming mature. They then migrate to nearby canes, stubs of pruned twigs, pithy weeds, or other protected sites and burrow to produce a winter shelter. Winter is spent as full-grown larvae in cocoons, and pupation occurs in spring. Moths fly and lay eggs over a period of a month during the period when young fruits are present. One generation is produced annually.
A. Filberworm adult and pupal case. DONALD OWEN, CALIFORNIA DEPARTMENT OF FORESTRY AND FIRE PROTECTION, BUGWOOD.ORG
B. Filbertworm larva and damage. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
C. Pea moth larva and damage. ART ANTONELLI, WASHINGTON STATE UNIVERSITY
D. Oriental fruit moth larva in peach. JIM KALISCH, UNIVERSITY OF NEBRASKA
E. Terminal wilting caused by Oriental fruit moth larval tunneling in peach shoot. CLEMSON UNIVERSITY–USDA COOPERATIVE EXTENSION SLIDE SERIES, BUGWOOD.ORG
F. Adult Oriental fruit moth. TODD M. GILLIGAN AND MARC E. EPSTEIN, USDA-APHIS ITP, BUGWOOD.ORG
G. Cherry fruitworm adult. MARK DREILING, BUGWOOD.ORG
H. Lesser appleworm larva and damage. P. J. CHAPMAN, NEW YORK STATE AGRICULTURAL EXPERIMENT STATION, BUGWOOD.ORG
LESSER APPLEWORM (Grapholita prunivora) is a minor pest of apple and also occurs on cherry and plum. Primary damage to apple occurs when larvae tunnel shallowly under the fruit skin. Twigs are also tunneled. Two generations per year are reported from Michigan to New York.
Grapholita delineana, the EURASIAN HEMP BORER, feeds primarily within the stems of hemp; however, larvae present in later generations may spin loose webs over leaves and clusters of developing seeds and damage young seeds.
1 Lepidoptera: Torticidae
TOBACCO BUDWORM (Heliothis virescens)1
HOSTS A wide range. Although solanaceous plants such as petunia, nicotiana, and tobacco are particularly favored, tobacco budworm also feeds on geranium, ageratum, chrysanthemum, snapdragon, strawflower, rose, and many other flowering plants. It is rarely a vegetable pest, unlike the corn earworm it resembles.
DAMAGE Feeding injuries are concentrated on flower buds, the caterpillars favoring the reproductive tissues. Small larvae may restrict feeding to bud tunneling; later stages may consume entire buds and chew petals. Foliage is rarely damaged, but tunneling of leaf buds may occur. Reduced flower production (“loss of color”) and ragged flowers result from tobacco budworm injuries.
DISTRIBUTION This insect is most damaging in areas of the southern U.S., as hard freezing temperatures can kill overwintering pupae. Mild winter conditions and some migration by the adult moths can allow significant infestations in more northern areas, however.
APPEARANCE Tobacco budworm is a moderate-sized insect, and caterpillars can reach 1½ inches when full grown. Color can be highly variable and is related in part to diet. Caterpillars may be nearly black to pale brown, with green and reddish forms also common. Banding may be present and prominent in darker caterpillars but indistinct in others. The presence of tiny “microspines” on some segments of the abdomen is used to separate this insect from the closely related corn earworm (tomato fruitworm/bollworm).
The adult moth is a typical “cutworm” form with a wingspan of about 1½ inches. The general color is pale green, and the forewing is marked with 4 light and slightly wavy bands. Pupae, which are found in the soil, are spindle-shaped and about ¾ inch long, typical of other cutworms.
LIFE HISTORY AND HABITS Tobacco budworm overwinters as a pupa in an earthen cell buried a few inches beneath the soil surface. In spring, adults emerge and are active in the early evening. After mating, females glue eggs singly onto flower buds and leaves. The young caterpillars emerge and feed on flower buds and petals. They become full grown in about 3 weeks, causing extensive injury. They then drop to the soil and pupate. In northern areas two generations per season are usually produced, with the highest caterpillar populations often occurring in August and early September. Four to five generations occur in the southern states.
RELATED SPECIES
TOMATILLO FRUITWORM (Heliothis subflexa) is a closely related species, and the adults are also quite similar in appearance to H. virescens. The caterpillars specialize in Physalis spp. and can be a serious pest of tomatillo fruit. Another closely related species is H. phloxiphaga, which develops on seeds and flowers of a wide variety of host plants, including sunflower, yarrow, asters, snapdragon, and phlox.
1 Lepidoptera: Noctuidae
B. Geranium bud tunneled by tobacco budworm. WHITNEY CRANSHAW
C. Eggs of tobacco budworm on geranium buds. WHITNEY CRANSHAW
D. Tobacco budworm larva chewing on petunia petals. JOSEPH BERGER, BUGWOOD.ORG
E. Tobacco budworm pupa. WHITNEY CRANSHAW
F. Adult of tobacco budworm. WHITNEY CRANSHAW
G. Tomatillo fruitworm larva and damage. WHITNEY CRANSHAW
H. Adult of the tomatillo fruitworm. WHITNEY CRANSHAW
I. Larva of Heliothis phloxiphaga. WHITNEY CRANSHAW
CORN EARWORM/TOMATO FRUITWORM/BOLLWORM (Helicoverpa zea)1
HOSTS A wide range, including many vegetables, field crops, fruits, flowers, and weeds. Corn, tomato, pepper, cotton, sorghum, and lettuce are among the crops most seriously damaged.
DAMAGE Larvae tunnel into ear tips of sweet corn, bore into various fruiting vegetables, and feed on leaves of lettuce and other vegetables. Corn earworm is considered one of the most destructive insects in the U.S., attacking many of the most important field and vegetable crops.
DISTRIBUTION Throughout North America except extreme northern areas. Where freezing winter temperatures prevent wintering, annual migrations originating from the southern U.S. and Mexico allow corn earworm to recolonize during summer and early fall.
APPEARANCE Young larvae are pale-colored but darken as they get older. A range of colors may be present, from pale green to pink or even black. Adult moths are typical cutworm form, with light brown wings that often have a dark spot in the center.
LIFE HISTORY AND HABITS Corn earworm is a tropical/subtropical species, and in parts of the southern U.S., development may be continuous. Winter temperatures limit survival in much of North America, and the species often dies out each year. In the northern U.S. and Canada, infestations arise from annual migrations of the adult moths from the southern U.S. and Mexico. Migration flights typically begin in June, but with favorable weather additional migrations can occur through the growing season.
Moths fly at night, feeding on nectar and laying eggs singly on suitable host plants. On sweet corn, eggs are laid on green silks; on tomato and pepper, they are usually laid on the new leaves near flowers of developing fruit. Once corn earworm has migrated into an area, damage may become somewhat cyclical, as peak numbers of eggs tend to be laid during the period around a full moon.
Eggs hatch in about 2–5 days, and the young caterpillars begin to tunnel into the plants. Corn earworm caterpillars usually feed for about 4 weeks before becoming full grown. Older larvae become highly cannibalistic, and it is fairly uncommon to find more than one in a single corn ear. When full grown, they drop from the plant, construct a small cell in the soil, and pupate. Adults emerge in 10–14 days and produce the next generation.
OTHER FRUIT-INFESTING CUTWORMS
Caterpillars of several other species of climbing cutworms are occasionally associated with trees in mid- to early spring. Most widespread is the SPECKLED GREEN FRUITWORM (Orthosia hibisci),1 which feeds on a wide range of deciduous trees and shrubs, including rose, apple, pear, cherry, peach, plum, crabapple, apricot, hawthorn, poplar, maple, oaks, willow, and white birch. The caterpillars feed primarily on foliage and normally cause little injury, but when developing buds and fruit are present, these may be chewed. These injuries can cause premature fruit drop, but when injuries are small the fruit continues to grow, becoming misshapen because of the injured area, and develops corky tissue around the old chewing wound.
Speckled green fruitworm spends the winter underground in the pupal stage. Adults are among the first moths to emerge, in March or April, and females lay eggs singly or in small groups near plant buds. The caterpillars feed on the new leaves and remain on the tree throughout their development. By early June the larvae become full grown, move to the soil and pupate. One generation is produced per year.
B. Adult corn earworm. DAVID SHETLAR
C. Corn earworm eggs. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
D. Young corn earworm larva. WHITNEY CRANSHAW
E. Corn earworm larvae showing range of coloration. WHITNEY CRANSHAW
F. Corn earworm larva, prepupa, and pupa. JIM KALISCH, UNIVERSITY OF NEBRASKA
G. Corn earworm in tomato, a “tomato fruitworm.” DAVID SHETLAR
H. Speckled green fruitworm. WHITNEY CRANSHAW
I. Speckled green fruitworm feeding on rose bud. ROBIN ROSETTA, OREGON STATE UNIVERSITY
J. Speckled green fruitworm feeding on apple. DAVID SHETLAR
K. Pear injured by speckled green fruitworm. WHITNEY CRANSHAW
GREEN FRUITWORM (Lithophane antennata)1 is found throughout North America but is particularly abundant in the Midwest and northeastern states. It is also active early in the season, with moths emerging to lay eggs in late winter and spring when evening temperatures persist above about 50° F for a few hours. Eggs are laid singly or in small masses, and the larvae feed on opening buds, leaves, and young fruit. Other species include PYRAMIDAL FRUITWORM (Amphipyra pyramidoides),1 FOURLINED FRUITWORM (Himella intractata),1 and YELLOWSTRIPED FRUITWORM (Lithophane unimoda).1 Injury is similar, and several species may be present concurrently. Life cycles vary somewhat, with Lithophane species overwintering as adult moths and pyramidal fruitworm as eggs. Damage to buds of various flowers and developing fruit is also sometimes produced by VARIEGATED CUTWORM (Peridroma saucia).1
1 Lepidoptera: Noctuidae
PICKLEWORM (Diaphania nitidalis)1
HOSTS Summer and winter squash are most commonly damaged. Cucumber, cantaloupe, and some pumpkins are other hosts.
DAMAGE Larvae tunnel buds, blossoms, and fruit.
DISTRIBUTION Pickleworm is restricted by winter weather to parts of southern Florida and Texas; however, northward migrations occur annually into the Carolinas.
APPEARANCE Pale in early stages, pickleworm caterpillars darken with age and may be somewhat greenish or pink (turning coppery before pupation) with a dark area behind the head. Full-grown caterpillars are about ½ inch. Adults are attractive moths with about a 1-inch wingspan. The wings are generally margined with a yellowish band, and there is a prominent tuft on the hind end of the body.
LIFE HISTORY AND HABITS Eggs are laid in small groups on buds, flowers, and new shoots. Larvae develop by feeding on the plant over a period of 2–3 weeks and then pupate in a thin cocoon tucked into folds of leaves or among crop debris. Adults usually disperse to weedy or woody areas where they spend the day and return to fields at night.
In the extreme southern U.S. where host plants are available year-round, activity may occur continuously. In Georgia and the Carolinas where hosts die out in winter and pickleworm fails to survive, 2–4 generations are typically produced per year following spring migration.
RELATED SPECIES
MELONWORM (Diaphania hyalinata)1 is closely related to pickleworm and shares an almost identical host range and distribution in North America. Despite its name, it does not damage watermelon, and cantaloupe is not a favored host. Melonworm larvae are pale yellow-green and restrict feeding almost entirely to foliage. Direct fruit damage is limited to the fruit surface and produces scarring of the rind.
B. Adult of the pyramidal fruitworm known as the copper underwing. LACY L. HYCHE, AUBURN UNIVERSITY, BUGWOOD.ORG
C. Variegated cutworm feeding on tomato. JIM KALISCH, UNIVERSITY OF NEBRASKA
D. Pickleworm tunneling squash fruit. GERALD HOLMES, CALIFORNIA POLYTECHNIC STATE UNIVERSITY AT SAN LUIS OBISPO, BUGWOOD.ORG
E. Pickleworms feeding on surface of squash fruit. GERALD HOLMES, CALIFORNIA POLYTECHNIC STATE UNIVERSITY AT SAN LUIS OBISPO, BUGWOOD.ORG
F. Adult pickleworm. CHAZZ HESSELEIN, ALABAMA COOPERATIVE EXTENSION SYSTEM, BUGWOOD.ORG
G. Melonworm. ALTON N. SPARKS JR., UNIVERSITY OF GEORGIA, BUGWOOD.ORG
H. Adult melonworm. ALTON N. SPARKS JR., UNIVERSITY OF GEORGIA, BUGWOOD.ORG
LIMABEAN POD BORER (Etiella zinckenella)1 damages various legumes in the western states; it can also be found but is less damaging in some southeastern states. Lupine, black locust, lima bean, snap bean, cow pea, and milk vetch are among the common hosts. Larvae destroy buds and blossoms and later tunnel into pods, destroying seeds and fouling pods with their excrement.
PECAN NUT CASEBEARER (Acrobasis nuxvorella)1 is found throughout areas where pecans are grown, from Florida to southern New Mexico. Adult moths are first present around late May/early June and lay eggs near the calyx of nutlets shortly after pollination. Newly hatched larvae feed first on buds and may cause flowers to abort. They later bore into the base of developing nutlets, sometimes destroying an entire cluster. Larvae feed for about 4 to 5 weeks and pupate within the nut. Adults emerge in July and lay eggs. Larvae from this second generation feed primarily on pecan shucks, causing little damage. Third-generation larvae feed little, moving to wintering shelter on twigs where they form a protective cocoon (hibernaculum).
CRANBERRY FRUITWORM (Acrobasis vaccinii)1 is an important pest of blueberry; cranberry and huckleberry are other common hosts. Eggs are laid around the blossom end of the fruit and larvae usually enter the fruit around the stem. Berries can be loosely webbed together, and conspicuous brown frass is kicked out of the fruit as the larvae feed. When full-grown, larvae move to the soil and construct a cocoon among surface debris or dug shallowly in the soil and pupate in late winter. One generation is produced annually. A related species is DESTRUCTIVE PRUNE WORM (A. tricolorella), also known as MINEOLA MOTH. It produces similar injuries to cherry and plum in most cherry-producing areas and spends winter as a partially grown larva that returns to feed on buds in midspring.
SUNFLOWER MOTH (Homoeosoma electella)1 is common in the southern and central U.S., developing in flower heads of sunflower, coneflower, zinnia, and related plants. The overwintering larvae are fairly sensitive to cold, but adults are highly migratory and flights from the south-central states may colonize areas into Canada and the northeastern states. Eggs are laid on flower heads and larvae feed on florets and then on the developing seeds, consuming or damaging numerous seeds. They also cover heads with a fine silk which, mixed with plant debris and frass, gives them an unattractive appearance. The caterpillars are quite distinctive, being purplish or reddish brown with light stripes running the length of the body.
The genus Dioryctria1 contains several species, collectively known as CONEWORMS, most commonly observed feeding on conifer cones. In the southeastern states, west to parts of Texas, SOUTHERN PINE CONEWORM (D. amatella) is common in pine seed cones. The young larvae overwinter on the bark and move to the young cones and shoots in late spring. Cankers produced by rust fungi are also commonly colonized. In the northern half of the U.S. and southern Canada, FIR CONEWORM (D. abietivorella) develops in Douglas-fir, fir, pine, and spruce. In cones it leaves a clean, pitch-free exit hole. It does considerable feeding on other parts of the plant, including buds, shoots, and even the trunk, in a manner similar to that of twig- and trunk-boring members of the genus (pages 336 and 430). Among the other species that develop predominantly in cones are SPRUCE CONEWORM (D. reniculelloides) in spruce and fir, BLISTER CONEWORM (D. clarioralis) on several southern pines, PINE CONEWORM (D. auranticella) on various pines, notably Austrian, in the Great Plains States, and WEBBING CONEWORM (D. disclusa) on various pines in eastern North America. In addition, some larvae of some Eucosma species develop within cones. Eucosma tocullionana2 is a common species associated with cones of eastern white pine.
EUROPEAN CORN BORER (Ostrinia nubilalis)3 is primarily a stem and stalk-boring species (page 358) that affects corn and a wide range of other vegetable and herbaceous ornamental plants. Fruiting structures may also be injured and the borer can be found developing within corn ears, pepper fruit, snap bean pods, and many other plants.
1 Lepidoptera: Pyralidae
2 Lepidoptera: Tortricidae
3 Lepidoptera: Crambidae
B. Larva of the pecan nut casebearer. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
C. Pecan nut caseborer damage to developing pecans. LOUIS TEDDERS, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
D. Adult of the pecan nut casebearer. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
E. Cranberry fruit larva and damage to blueberry. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
F. Sunflower moth larva and damage to coneflower. JIM KALISCH, UNIVERSITY OF NEBRASKA
G. Adult sunflower moths. PHIL SLODERBECK, KANSAS STATE UNIVERSITY, BUGWOOD.ORG
H. Cone of Austrian pine damaged by pine coneworm. WHITNEY CRANSHAW
I. Webbing coneworm larva in developing cone. LARRY R. BARBER, USDA FOREST SERVICE, BUGWOOD.ORG
J. External evidence of feeding injury by Eucosma tocullionana in white pine cone. STEVEN KATOVICH, USDA FOREST SERVICE, BUGWOOD.ORG
K. Entry hole produced by European corn borer in pepper. RIC BESSIN, UNIVERSITY OF KENTUCKY
L. European corn borer in pepper fruit. RIC BESSIN, UNIVERSITY OF KENTUCKY
OTHER FRUIT- AND SEED-INFESTING CATERPILLARS
GRAPE BERRY MOTH (Paralobesia viteana)1 is an eastern species that develops on grape. The spring generation of larvae is most damaging as larvae web together clusters of flower buds and consume most of them. Tender shoots and newly set berries may also be eaten. Summer-generation larvae develop in the berries and may feed on 2 or 3 berries while developing. Two generations are produced annually, with winter spent as pupae.
EUROPEAN GRAPEVINE MOTH (Lobesia botrana)1 has a very wide range of plant hosts but is most often found feeding on wine grapes and flax-leaved daphne. Potentially serious damage can be done to wine grapes when the caterpillars feed on bud clusters, flowers, and fruit. In addition to these direct losses, feeding injuries to fruit also create wounds that allow infections with Botrytis fungi. The first North American detections of this insect were in California in 2009.
BANDED SUNFLOWER MOTH (Cochylis hospes)1 is common in the northern Great Plains but can be found from northern Texas east to North Carolina. Newly hatched larvae are white with a dark head, but body color changes throughout larval development and can vary from pink or yellow to purple or green at maturity. Females lay eggs in the base of flowers in late July, and larvae first feed on the florets. They later partially consume several seeds before moving to the soil and creating an overwintering cell in which they spend the winter. Pupation occurs the following June. The adult moths are straw-colored with a wingspan of about ½ inch.
Several species of LEAFROLLER MOTHS (page 128) can cause surface wounding of fruit. The wounding occurs when larvae produce a shelter of leaves that also includes buds and developing fruit. Although these larvae most often feed on leaves, incidental damage to fruit can occur that results in significant distortion of mature fruit. Among the important leafrollers that have potential to damage fruit are EYESPOTTED BUD MOTH (Spilonota ocellana),1 REDBANDED LEAFROLLER (Argyotaenia velutinana),1 OBLIQUEBANDED LEAFROLLER (Choristoneura rosaceana),1 ORANGE TORTRIX (Argyrotaenia citrana),1 BLACKHEADED FIREWORM (Rhopobota naevana),1 OMNIVOROUS LEAFTIER (Platynota stultana),1 and LIGHT BROWN APPLE MOTH (Epiphyas postvittana).1
Caterpillars of NAVEL ORANGEWORM (Amyelois transitella)2 develop in a wide range of fruits and nuts. This species is particularly damaging to fig and almond in southern California. Eggs are laid in fissures of fruit and in cracks of nuts after hulls begin to split. Larvae are cream-colored to slightly pinkish with a reddish-brown head capsule.
PEACH TWIG BORER (Anarsia lineatella)3 develops as a borer in both twigs and fruit in peach. The first-generation larvae, usually present in late April and May, tunnel terminals, producing “shoot strikes” indicated by wilting foliage. Adults from this generation emerge in late spring and subsequently lay eggs on twigs, small leaves, and developing fruit. The caterpillars may move about the plant, and fruit is attacked after the pit begins to harden. Peach twig borer is most common and important as a peach pest in the western U.S. but does occur over much of the country where peaches are produced. Almond and apricots are other hosts, but peach twig borer rarely injures their fruits.
TOMATO PINWORM (Keiferia lycopersicella)3 occurs throughout warmer areas of the southwestern states. Tomato is the primary host, although some related plants such as eggplant, potato, and some nightshade weeds also host the insect. Eggs are laid in small clusters on the leaves, and young larvae mine leaves. Later they emerge and fold leaves, feeding as general defoliators. As the larvae get older, they darken from orange-brown to nearly purplish. Older larvae may tunnel fruit, causing most damage. Fruit injuries are concentrated around the stem end, but tunneling may extend to the core. Activity and reproduction may continue year-round if conditions permit. Seven to eight generations per year are commonly produced in southern California.
A. Larva of a European grapevine moth. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA IPM PROGRAM
B. Banded sunflower moth larva. FRANK PEAIRS
C. Fruit surface injury produced by obliquebanded leafroller. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA IPM PROGRAM
D. Adult of the orange tortrix. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA IPM PROGRAM
E. Larva of the orange tortrix. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA IPM PROGRAM
F. Larva, pupa and damage to almond by navel orangeworm. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA IPM PROGRAM
G. Adult navel orangeworm. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA IPM PROGRAM
H. Omnivorous leaftier larva and injury to strawberry. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
I. Peach twig borer tunneling into peach fruit. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
J. Peach twig borer larva and injury to peach. EUGENE NELSON, COLORADO STATE UNIVERSITY
K. Peach twig borer larva. ROBIN ROSETTA, OREGON STATE UNIVERSITY
L. Tomato pinworm damage to surface of tomato fruit. ALTON N. SPARKS JR., UNIVERSITY OF GEORGIA, BUGWOOD.ORG
M. Tomato pinworm larvae exposed from leaf mine. JAMES HAYDEN, MICROLEPIDOPTERA ON SOLANACEAE, USDA APHIS ITP, BUGWOOD.ORG
ARTICHOKE PLUME MOTH (Platyptilia carduidactyla)4 is the most important insect pest of globe artichoke, but the insect is present over much of North America, where it develops in various thistles. Larvae may feed on all aboveground parts of the plant but create problems when they enter the leaves of the harvestable artichoke buds. This occurs when eggs are laid near buds and early stage larvae typically tunnel into outer leaves, progressively boring more deeply within the buds as they get older. Two generations per year are reported from Minnesota, three from California.
Adults are small yellowish-brown moths with unusual wings that are extremely narrow and held perpendicular to the body, giving them a T-shape. This appearance is typical of other members of the plume moth family (Pterophoridae), represented by some 150 species in North America, and it is the odd-looking adults that usually attract attention. Larvae feed on buds and seedpods and occasionally bore into stems of various plants, but rarely produce noticeable injury. A few species associated with cultivated plants include GERANIUM PLUME MOTH (Amblyptilia pica),4 which feeds on a wide variety of plants, occasionally damaging buds and flowers of cultivated geraniums and snapdragons; GRAPE PLUME MOTH (Geina persicelidactylus)4 which feeds on grape leaves, often feeding within a leaf fold of the terminal leaf; MORNING GLORY PLUME MOTH (Emmelina monodactyla),4 which feeds on leaves of various morning-glory family (Convolvulaceae) plants; and SNAPDRAGON PLUME MOTH (Stenoptilodes antirrhina),4 which develops in the buds, seedpods, and stems of snapdragon in California.
COTTON SQUARE BORER (Strymon melinus)5 develops on various legumes and plants in the mallow family (e.g., okra, cotton, hibiscus). Early-stage caterpillars feed on leaves, causing little injury. Older larvae may do some tunneling into pods of bean, okra, and other plants but are rarely abundant in gardens. Cotton square borer occurs throughout the U.S. and southern Canada but is abundant only in the southern U.S. The adult is an attractive butterfly known as GRAY HAIRSTREAK. Winter is spent in the chrysalis, with adults emerging in spring when host plants become available. Eggs are laid singly in plants. Young larvae feed on leaves, and older larvae concentrate more on reproductive tissues. Pupation occurs in a yellow or brown chrysalis marked with black spots. Two generations per year normally occur in the northern part of range and up to four in the south.
Larvae of the “YUCCA MOTHS” develop by feeding on the developing seeds of various Yucca spp.; however, the relationship between these insects and their host plants is mutualistic, as the adult moths are essential to the pollination of the plant. Yucca produce a sticky pollen that is collected by the yucca moths, which then actively move it to the floral stigmas, allowing pollination. At this time eggs are either inserted into the plant ovary (Tegeticula spp.)6 or laid on the pedicel or petals (Parategeticula pollenifera).6 The larvae that subsequently hatch eat a few of the seeds, but allow many to survive.
Most yucca moths are within the Tegeticula yucasella complex, which consists of 13 species, all of which develop into moderate-sized moths (wingspan typically ¾–1 inch) that are primarily white or light brown. Each is associated with only a few species of yucca, sometimes only a single species. The range of many has extended with the use of yucca in ornamental plantings, and some are presently found as far north as New England.
CITRUS PEELMINER (Marmara gulosa)7 produces meandering, serpentine-form mines under the surface of various fruits in the southwestern U.S. and northern Mexico It is most commonly observed on thinned-skinned citrus, but can develop in fruit of a very wide range of plants, including grape, walnut, and cotton. It can also occur as a cambium miner in twigs of oleander, willow, citrus, and other hosts.
1 Lepidoptera: Tortricidae
2 Lepidoptera: Pyralidae
3 Lepidoptera: Gelechiidae
4 Lepidoptera: Pterophoridae
5 Lepidoptera: Lycaenidae
6 Lepidoptera: Prodoxidae
7 Lepidoptera: Gracillaridae
A. External symptoms of injury by artichoke plume moth. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA IPM PROGRAM
B. Adult artichoke plume moth. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA IPM PROGRAM
C. Larva of artichoke plume moth. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA IPM PROGRAM
D. Adult snapdragon plume moth. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
E. Damage to pods of snapdragon by snapdragon plume moth. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
F. Adult of the cotton square borer, the gray hairstreak. WHITNEY CRANSHAW
G. Larva of a cotton square borer. WHITNEY CRANSHAW
H. Yucca moth. DAVID SHETLAR
I. Yucca moth feeding at flower. DAVID SHETLAR.
J. Exit holes made in yucca seed pods by emerging yucca moths. WHITNEY CRANSHAW
K. Larval tunneling of citrus rind by citrus peelminer. WHITNEY CRANSHAW
EUROPEAN APPLE SAWFLY (Hoplocampa testudinea)1 is an introduced species found from New England south to West Virginia and west to Ontario. An isolated infestation also occurs on Vancouver Island, British Columbia. This species can be a serious pest of apple fruit and also damages crabapple.
Adults become active around the time apple trees begin to bloom and are present for about 2 weeks. Females lay eggs in the blossoms, and the newly hatched larvae feed on the surface of the young apples. These wounds may cause fruit to abort, but if fruit remains, injuries develop as spiral scars on the skin. After molting, later-stage larvae tunnel into the fruit and ultimately feed about the core. A large exit hole is produced from which reddish-brown frass is continually expelled.
The larvae are pale brown with a dark head and very short appendages. They may feed on several fruits in a cluster before becoming full grown. They then drop to the ground and winter in a cocoon. Pupation occurs in spring, a few weeks before adults emerge.
RELATED SPECIES
A few native Hoplocampa species are associated with wild and cultivated cherry, including H. lacteipennis and H. cookei (CHERRY FRUIT SAWFLY). Cherry fruit sawfly is found in the Pacific Northwest, where it has also been reported to occasionally damage plum.
1 Hymenoptera: Tenthredinidae
SCARAB BEETLES FOUND AT FRUIT AND FLOWERS
JAPANESE BEETLE (Popillia japonica)1 is an important insect pest in much of eastern North America and has recently become established in limited areas within some western states. Larvae are a type of white grub that chew roots of turfgrass and adults damage the flowers and foliage of a wide variety of plants growing in yards and gardens. Flower feeding by Japanese beetle is particularly common on rose and hibiscus.
FALSE JAPANESE BEETLE (Strigoderma arboricola)1 occurs widely east of the Rockies and is particularly common in the midwestern U.S. The adult is very similar in appearance to Japanese beetle but is slightly duller-colored and lacks the characteristic row of white tufts along the sides. Larvae feed on plant roots and are minor pests of potato, onion, grass, arborvitae, yew, and spruce. Adults are highly attracted to white and may cluster on white flowers during the brief period in early summer when they are active. False Japanese beetle is limited to areas of sandy soil and is known locally as “sandhill chafer” in parts of western Nebraska and eastern Colorado.
Adults of ROSE CHAFER (Macrodactylus subspinosus)1 feed on leaves and particularly blossoms of a wide variety of plants, producing skeletonizing injuries. Rose and peony are highly preferred. Various berries, peach, cherry, amur corktree, mountain-ash, grape, Virginia creeper, some birches, plum, cherry, and crabapple are other common hosts. Rose chafer contains a toxic heart poison, and birds can be poisoned by eating it.
A. Damage by apple sawfly. ERIC R. DAY, VIRGINIA POLYTECHNIC INSTITUTE AND STATE UNIVERSITY, BUGWOOD.ORG
B. Mating pair of apple sawflies. KARL HILLIG
C. Apple sawfly larva. JOE OGRODNIK COURTESY OF NEW YORK AGRICULTURAL EXPERIMENT STATION
D. Japanese beetle feeding rose. WHITNEY CRANSHAW
E. False Japanese beetle feeding on prickly poppy. WHITNEY CRANSHAW
F. Rose chafer on rose hips. CLEMSON UNIVERSITY-USDA COOPERATIVE EXTENSION SLIDE SERIES, BUGWOOD.ORG
Rose chafer is restricted to areas of the northeastern U.S. and eastern Canada where light, sandy soils are present. The larvae feed on roots of grasses and some weeds, apparently causing little injury. Adults emerge in June and live about a month. They are about ½ inch and more elongate than most scarab beetles, with gray or brown wings, a generally gray abdomen, and long orange legs. In the southwestern U.S. a related species is present, WESTERN ROSE CHAFER (M. uniformis), but it is rarely damaging.
ASIATIC GARDEN BEETLE (Maladera castanea)1 feeds on leaves and flowers of more than 100 different trees, shrubs, and flowers, including asters, dahlias, chrysanthemums, and roses. Adults are chestnut brown beetles, about 
to ⅜ inch long that fly and feed at night. The Asiatic garden beetle is currently found over a broad area of the northeast, from Michigan to New England and southward to South Carolina.
HOPLIA BEETLE (Hoplia callipyge),1 also known as “grapevine hoplia,” is a minor pest of certain flowers and fruits in many western states. Injury to white and light-colored roses is most commonly reported, but flowers of ceanothus, calla lily, California poppy, magnolia, lupine, and various legumes are also commonly eaten by adult beetles. Fruit clusters of grape are sometimes destroyed by this feeding, which usually occurs from mid-March through early May. Adults are about ¼ to ⅜ inch long and brownish or reddish brown with silvery scales on the back, providing a mottled appearance. Larvae feed on plant roots. One generation is produced annually. A related species in southwestern Canada that sometimes feed on flowers and small fruits is H. modesta; H. oregona has similar habits in the Pacific Northwest.
BUMBLE FLOWER BEETLE (Euphoria inda)1 is a moderately large, fuzzy scarab beetle. Adults are sometimes observed, often in small masses, at ooze from plant wounds and on fermenting fruit. Occasionally they damage flowers, including daylily, large thistles, rose, and strawflower. Larvae develop in decaying organic matter, preferring animal manures, and may be common in compost piles. Container-grown plants using fresh compost are sometimes infested by bumble flower beetle larvae, which may incidentally chew on roots. Bumble flower beetle is found throughout most of the area east of the Rocky Mountains. It overlaps in range with E. sepulcralis, which is restricted to eastern states. The COMMON FLOWER SCARAB, E. kerni, may be common at flowers in the western U.S., feeding on pollen of a variety of garden flowers.
Bumble flower beetle feeding on ripe grape. HAROLD J. LARSEN, COLORADO STATE UNIVERSITY
Two species of very large, green June beetles in the genus Cotinus are sometimes found feeding on ripe, particularly overripe fruit. In the eastern half of the U.S., ranging into Texas and Kansas, the GREEN JUNE BEETLE (Cotinus nitida)1 is present. In areas of the southwestern states the related FIG EATER BEETLE (C. mutabilis) occurs. Larvae of both are a type of white grub that develop in decaying plant matter. Injury to turfgrass may occur as the larvae tunnel extensively through lawns, feeding little on live roots but disturbing soil and creating large surface mounds. In eastern North America, another large scarab that may be found feeding on leaves and fruit of grape is Pelidnota punctata,1 known variously as the “grapevine beetle” or “spotted pelidnota.” Larvae develop in rotting wood.
1 Coleoptera: Scarabeaidae
B. Hoplia beetle on rose flower. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA STATEWIDE IPM PROGRAM
C. Green June beetle on ripe fruit. DAVID SHETLAR
D. Euphoria kerni feeding on thistle pollen. WHITNEY CRANSHAW
E. Bumble flower beetle in cardoon flower. WHITNEY CRANSHAW
F. Spotted pelidnota. DAVID SHETLAR
SAP BEETLES AND OTHER FRUIT-DAMAGING BEETLES
Sap beetles (Nitidulidae family) are common around fermenting fruit, oozing wounds of plants, and areas of decaying vegetation. Most do not cause any direct injuries to fruit or vegetables but are attracted to overripe fruit and can be a nuisance. Some species may also be involved in movement of bacteria and fungi, notably spores of Ceratocystis fagacearum, the causal organism of oak wilt. Approximately 180 sap beetle species occur in North America. Most are oval to nearly rectangular in form and have distinctly clubbed antennae. Several species in the fruitworm beetle family (Byturidae) also damage fruits.
DUSKY SAP BEETLE (Carpophilus lugubris)1
HOSTS Maturing sweet corn, most overripe fruits and vegetables, and trees infected with various bacteria and fungi.
DAMAGE Unlike most sap beetles, dusky sap beetle can directly injure intact sweet corn ears. Larvae chew on the developing kernels, although there is rarely any external evidence of infestation. Dusky sap beetle has been involved in moving spores of the oak wilt pathogen to wounds of healthy trees.
DISTRIBUTION Throughout most of North America, common.
APPEARANCE Adults are about ⅛ inch and dull dark gray-brown with short wing covers, each having a light brown band at the base. Larvae are pale-colored, slightly flattened, with a brown head and a dark area on the hind segment.
LIFE HISTORY AND HABITS Overwintered adults and pupae may be found in piles of discarded fruit, partially buried vegetable debris, or under the bark of trees with oozing wounds. Adults are active on warm days in early spring. At this time they feed and begin to lay eggs around decaying vegetation and on sap or bacterial ooze from damaged trees. Larvae can complete development in as little as 3 weeks, and pupation occurs in the soil. Two to three generations are probably produced in most years. Beetles are attracted to sweet corn shortly after pollen begins to be shed, at about the time that corn silk first begins to turn brown. Dusky sap beetle adults are present from early spring through November, with peak numbers often in late spring and midsummer.
OTHER SAP BEETLES
FOURSPOTTED SAP BEETLE (Glischrochilus quadrisignatus)1 is common in the northern U.S. and southern Canada. It is sometimes known as the “picnic beetle” because it is often attracted quickly and in nuisance numbers to ripe fruit, pickled vegetables, and fermented beverages during outdoor dining. It also commonly visits damaged or overripe fruits and vegetables in the field, and it may chew on the silk of sweet corn and readily invade cavities made by corn earworm and European corn borer. Adults are about ¼ inch and shiny black with 4 orange-red spots. G. fasciatus, another common species, resembles fourspotted sap beetle but lacks the distinctive spotting.
STRAWBERRY SAP BEETLE (Stelidota geminata)1 is a common pest of strawberry in the eastern U.S. It may aggregate in large numbers on ripening fruit, where the beetles feed and lay eggs. They can be important nuisance problems, particularly in pick-your-own operations. Adults are small (ca. ⅛ inch) mottled brown beetles. Strawberry sap beetle has a more restricted host range than many other sap beetles and is damaging only to strawberry. Two generations are typically produced annually.
1 Coleoptera: Nitidulidae
A. Dorsal and ventral views of the sap beetle Carpophilus ligneus. JIM KALISCH, UNIVERSITY OF NEBRASKA
B. Sap beetles feeding on ooze from wound of honeylocust. DAVID SHETLAR
C. Dusky sap beetle adults and larvae in sweet corn. EUGENE NELSON, COLORADO STATE UNIVERSITY
D. Dusky sap beetles massed on overripe melon. WHITNEY CRANSHAW
E. A “picnic beetle,” Glischrochilus quadrisignatus. JIM KALISCH, UNIVERSITY OF NEBRASKA
F. Larva of a Glischrochilus species sap beetle. JIM KALISCH, UNIVERSITY OF NEBRASKA
G. Strawberry sap beetle. TOM MURRAY
H. Strawberry sap beetle larvae in strawberry. NATALIE HUMMEL, LOUISIANA STATE UNIVERSITY AGCENTER, BUGWOOD.ORG
RASPBERRY FRUITWORMS (Byturus spp.)1 are common insects associated with raspberry and loganberry throughout the northern U.S. and southern Canada. Adults of EASTERN RASPBERRY FRUITWORM (B. rubi) emerge in late April or early May, about the time leaves first emerge. They feed on the midrib of the unfolding leaves, resulting in ragged, elongate holes. They may then feed on the unopened flower buds and can destroy an entire bud cluster and further damage leaves in a skeletonizing manner. Eggs are laid on or sometimes in unopened blossom buds. The larvae then bore into the developing fruit and are distinctive in having two rows of light-colored, stiff hairs on the back. When full grown, the larvae drop from the plant and pupate in the soil. One generation is produced per year. The life history is likely similar for WESTERN RASPBERRY FRUITWORM (B. bakeri), common in western areas, and for B. unicolor, found in many areas of Canada.
Adults of the SPOTTED ASPARAGUS BEETLE (Crioceris duodecimpunctata)2 are commonly observed on ferns of asparagus. Larvae develop within asparagus seeds.
Adults of SPOTTED CUCUMBER BEETLE (Diabrotica undecimpunctata howardi)2 (also known as SOUTHERN CORN ROOTWORM) feed on leaves and flowers of a wide variety of plants and occur widely across North America east of the Rockies. The overwintering stage is an adult that emerges early in the growing season, and there are subsequent multiple (often 2) generations produced annually, allowing the insect to be present throughout much of the year. In the western states it is replaced by the subspecies WESTERN SPOTTED CUCUMBER BEETLE, Diabrotica undecimpunctata undecimpuncta. Dahlia, peony, and hibiscus are among the flowers most commonly damaged by this insect. These insects also chew on the developing fruits and seeds of many garden plants, including green beans, tomato, eggplant, and, occasionally, some tree fruits (apricot, peach); however, cucurbit family plants—melons, pumpkins, squash, cucumbers—are particularly favored.
Western spotted cucumber beetle feeding on bean pod. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
A number of other closely related insects are also commonly associated with fruit and flowers of cucurbits, including STRIPED CUCUMBER BEETLE (Acalymma vittatum),2 WESTERN STRIPED CUCUMBER BEETLE (A. trivittatum), CHECKERED MELON BEETLE (Paranapiacaba tricincta),2 and WESTERN CORN ROOTWORM (Diabrotica virgifera virgifera).2 With the exception of the last, the larval stages of all of these also develop on the roots of cucurbits. Those larvae that do develop on cucurbits (“rindworms”) will sometimes move into the rind of fruit lying on the ground (“rindworms”), producing tunnels that scar and, often more importantly, wounds that allow entrance of decay pathogens. Larvae of the western corn rootworm develop solely on roots of corn, and the adults that emerge in early summer often concentrate feeding on green corn silk. However, they also favor feeding on blossoms and pollen of cucurbits and may be seen in co-occurrence with “cucumber beetles” in squash blossoms.
Striped cucumber beetle feeding on cosmos flower. WHITNEY CRANSHAW
1 Coleoptera: Byturidae
2 Coleoptera: Chrysomelidae
B. Larva of a raspberry fruitworm feeding in cap of ripe raspberry. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
C. Spotted asparagus beetle. WHITNEY CRANSHAW
D. Spotted asparagus beetle larva feeding on asparagus fruit. WHITNEY CRANSHAW
E. Spotted cucumber beetles, and one western corn rootworm, in squash blossom. WHITNEY CRANSHAW
F. Spotted cucumber beetle feeding on flower. WHITNEY CRANSHAW
G. Corn silk clipped by western corn rootworm. DAVID KEITH, UNIVERSITY OF NEBRASKA
H. Fruit scarring by striped cucumber beetle adults. WHITNEY CRANSHAW
I. Striped cucumber beetle larva on surface of melon fruit contacting soil. WHITNEY CRANSHAW
J. Checkered melon beetles feeding on sunflower pollen. WHITNEY CRANSHAW
K. Checkered melon beetle and striped cucumber beetles on surface of ripe melon. WHITNEY CRANSHAW
POLLEN-FEEDING BEETLES COMMON AT FLOWERS
Many types of beetles feed on pollen in the adult stage and may be conspicuous at flowers. In late summer and early fall, SOLDIER BEETLES (Chauliognthus spp.)1 are often commonly observed on flowers, particularly yellow-flowered plants such as goldenrod and rabbitbrush. These are moderately large beetles (ca. ½–¾ inch), predominantly yellow or orange and black, with soft forewings. Large numbers may be seen on particularly favored plants, with many—often most—coupled (male on top). Eggs are laid in masses in the soil, and the larvae develop as predators of insects that occur in or on soil. Common species in eastern North America include C. marginatus (MARGINED LEATHERWING) and C. pensylvanica (GOLDENROD LEATHERWING); C. scutellaris and C. basalis (COLORADO SOLDIER BEETLE) are common species in the High Plains States. Several other genera of soldier beetles also occur in North America that are predators in the adult stage, but the Chauliognathus species limit feeding to pollen.
Many BLISTER BEETLES2 also feed on pollen and nectar but may feed on flower petals, particularly of legumes. Most often observed are various black or gray Epicauta spp., including the ubiquitous BLACK BLISTER BEETLE (E. pensylvanica), a very common species east of the Rocky Mountains present on flowers in late summer. Other genera common on flowers include Pyrota spp., often brightly marked with yellow and black, Lytta spp., often with some metallic sheen, and Nemognatha spp., usually pale orange and with elongated mouthparts that allow them to extract nectar from flowers. Larvae of blister beetles develop variously either on eggs of grasshoppers or on bee larvae within nests of ground-nesting bees.
TUMBLING FLOWER BEETLES3 are small (ca. ⅛–¼ inch), wedge-shaped beetles with a distinctive “pintail.” They can make small, twisting jumps when disturbed, producing a tumbling that may allow them to escape predators. Most tumbling flower beetles observed in flowers are in the genera Mordella or Mordellistena, which are either predominantly dark gray or black and brown, respectively. Larval habits of the tumbling flower beetles are poorly known, but the family includes species that develop in decayed wood, as fungivores or predators, or in the pith of plants. In addition to flowers, where they feed on pollen, the adult beetles often collect on dead trees and fallen logs.
The ANTLIKE FLOWER BEETLES4 are small (ca. 
–⅛ inch) beetles that rarely attract attention except when noticed within flowers. It is a large family of beetles, with more than 230 North American species, but those most commonly found in flowers are in the genera Anthicus, Ischyropalpus, and Notoxus; the last are distinguishable by a hornlike projection of the thorax that extends over the head. Larvae feed on decaying plant matter.
Many kinds of SOFT-WINGED FLOWER BEETLES5 are common at flowers. Most conspicuous are Collops spp., which are about ¼ inch long, brightly patterned, with wing covers that do not completely cover the end of the abdomen. Collops adults do feed on pollen but are primarily predaceous on many small insects that may visit flowers. Other common genera of soft-winged flower beetles found on flowers are less distinctively marked and smaller, including those in the genera Trichochrous and Listrus, which are dark gray or mottled gray. Larvae of most soft-winged flower beetles are thought to be predators that live in the soil.
B. Mating pairs of the soldier beetle, Chauliognathus pensylvanica. WHITNEY CRANSHAW
C. Black blister beetle feeding on pollen. WHITNEY CRANSHAW
D. Blister beetles, Nemognatha species. WHITNEY CRANSHAW
E. Tumbling flower beetles. JIM KALISCH, UNIVERSITY OF NEBRASKA
F. An antlike flower beetle. WHITNEY CRANSHAW
H. Soft-winged flower beetles, Listrus species. DAVID SHETLAR
G. A soft-winged flower beetle, Collops quadriguttatus. DAVID SHETLAR.
SPOTTED FLOWER BUPRESTIDS (Acmaeodera spp.)6 are metallic wood borers that feed on pollen and are normally seen resting on flowers. Approximately 150 species occur in North America, most in the southwestern states. Most have some light-colored spotting and are slightly hairy. Larvae develop as borers within plants, but none are considered pest species.
Some longhorned beetles7 also visit flowers, particularly daisies, sunflowers, and other composites. Batyle suturalis and B. ignicollis are two species common over a broad area of central North America. Other “flower longhorns” commonly seen at flowers occur in the genera Typocerus, Leptura, and Crossidius. Although all of these develop as borers of plants in the larval stage, none are damaging to cultivated plants. However, some longhorned beetles that are pollen feeders are important as wood borers, notably the LOCUST BORER (Megacyllene robiniae)7 (page 440), commonly observed on goldenrod and other yellow-flowered plants in late summer.
1 Coleoptera: Cantharidae
2 Coleoptera: Meloidae
3 Coleoptera: Mordellidae
4 Coleoptera: Anthicidae
5 Coleoptera: Melyridae
6 Coleoptera: Buprestidae
7 Coleoptera: Cerambycidae
FRUIT, FLOWER, AND SEED WEEVILS
Adult weevils, or snout beetles, possess an elongated “snout,” at the end of which are chewing mouthparts. These are usually used to chew into plants, and larval stages of many species develop inside seeds, fruits, and flower buds. Weevils present in yards and gardens include representatives of three weevil families: Curculionidae (snout and bark beetles), Attelabidae (leaf-rolling weevils), and Brentidae (straightnosed weevils).
Many of the weevils that develop on seeds or fruit are known as curculios, a reference to the family name. Other weevils develop as borers of stems (page 362) or as root feeders (page 472), and a few develop on foliage (page 196) or as leafminers (page 216). The bark beetles (pages 350 and 452) are now also classified as a type of weevil.
PLUM CURCULIO (Conotrachelus nenuphar)1
HOSTS Plum, apple, and apricot are most seriously damaged, but peach, nectarine, quince, cherry, pear, hawthorn, wild plum, and native crabapple are also hosts.
DAMAGE Feeding and egg-laying wounds by adults produce scarring and distortion of developing fruit, often inducing premature fruit drop. This feeding is often characterized as a D-shaped scar on mature fruit. Wounds may provide entry for brown rot fungus. Larvae tunnel fruit of plum, peach, and apricot.
DISTRIBUTION Generally distributed over the eastern and midwestern states and eastern Canada. Localized infestations occur in parts of Utah, the Pacific Northwest, eastern Texas, and Oklahoma.
APPEARANCE Adults are generally gray to black snout beetles, about ¼ inch, with light gray and brown mottling. The wing covers are rough with 2 prominent humps and 2 smaller ones. Larvae, found in fruit, are legless, creamy white grubs with a dark head; they are about ⅜ inch when full size.
LIFE HISTORY AND HABITS Adult weevils winter under covering debris in the vicinity of previously infested trees. They begin to move to trees when average spring temperatures exceed 55–60° F for 3–4 days, and migration continues for a month or more. When small fruits become available, females chew a small pit and insert eggs. They then make a crescent-shaped cut below the egg pocket, leaving a small flap of dead skin on the surface of the fruit.
B. The flower longhorn Batyle suturalis. WHITNEY CRANSHAW
C. The flower longhorn Typocerus velutinus. JONATHAN YUSCHOCK.
D. Feeding scars produced by plum curculio. DAVID SHETLAR
E. Plum curculio larva in sour cherry. JIM KALISCH, UNIVERSITY OF NEBRASKA
F. Plum curculio adult. DAVID SHETLAR
Eggs hatch in about 1 week, and larvae feed in the fruit for about 3 weeks. In some fruit, such as apple, larvae survive poorly, apparently crushed by growing tissues. Larvae that develop successfully cut their way out and drop to the soil. They dig and produce a small earthen cell where they pupate. Adults emerge in 4–6 weeks. In most of its range, plum curculio has only one generation per year, and adults feed on maturing apples before moving to hibernation sites. Two generations are reported in Oklahoma and Texas.
ROSE CURCULIO (Merhynchites bicolor)2
WESTERN ROSE CURCULIO (Merhynchites wickhami)2
HOSTS Rose, particularly wild rose.
DAMAGE Rose curculio damages roses by making feeding punctures in flower buds, resulting in ragged flowers. During periods when buds are not common, feeding occurs on the tips of shoots, killing or distorting the shoots. A “bent neck” condition of rose, similar to that which rose midge may produce (page 582), can be caused by rose curculio feeding wounds that puncture developing stems.
DISTRIBUTION The rose curculio is the dominant species east of the High Plains, but it can be found in areas of western North America. The western rose curculio is usually the dominant species found in the Pacific States and east to Colorado and Alberta.
APPEARANCE Adults are about ⅕ inch with a pronounced dark-colored “beak,” which is longer on the males. In most areas the wing covers, thorax, and head are reddish and the remainder of the body black. In many western states, however, this species may have metallic green or blue-green coloration.
LIFE HISTORY AND HABITS Adults become active in late spring and lay eggs in developing flowers. The larval (grub) stage feeds on the reproductive parts of the flower. Blossoms on the plant, including those clipped off by a gardener, are suitable for the insect to develop. When full grown, the grubs fall to the soil and form an underground cell, pupating the following spring. There is one generation per year.
Wound produced in rose bud by rose curculio. WHITNEY CRANSHAW
OTHER SEED-, FRUIT-, AND FLOWER-DAMAGING WEEVILS
PLUM GOUGER (Coccotorus scutellaris)1 makes numerous feeding punctures on the surface of maturing plums, many of which result in a flow of clear ooze at the feeding site. Eggs are laid in some of the punctures, and the larvae develop in the pit. Adults spend the winter in the pit, and removal of infested fruit at the end of the season can help with control.
Oozing from feeding wound by plum gouger. WHITNEY CRANSHAW
APPLE CURCULIO (Anthonomus quadrigibbus)1 is found in the midwestern and eastern U.S. and eastern Canada. Damage to apple is infrequent, resulting mostly from feeding punctures that heal as sunken areas on the fruit. Larvae cannot develop in growing apple fruit, only in early-season dropped fruit. Development most commonly occurs in other hosts, notably amelanchier, hawthorn, and wild crabapple.
CHERRY CURCULIO (Anthonomus consors)1 is a minor pest of sour cherry and chokecherry in the Rocky Mountain region. Adults chew small holes in the base of flowers and cause abortion of developing fruit. The skin of older fruit is pitted by this injury. Eggs are inserted into fruit, and larvae tunnel the fruit, ultimately feeding on the pit. One generation is produced per year.
B. Rose curculio chewing into bud. JIM KALISCH, UNIVERSITY OF NEBRASKA
C. Flower petal injuries produced by rose curculio. WHITNEY CRANSHAW
D. Bent terminal of rose resulting from rose curculio feeding wound. WHITNEY CRANSHAW
E. Plum gouger. DAVID LEATHERMAN
F. Apple curculio. DAVID SHETLAR
G. Cherry curculio. WHITNEY CRANSHAW
H. Larva of cherry curculio in cherry pit. WHITNEY CRANSHAW
In the eastern states, STRAWBERRY BUD WEEVIL (Anthonomus signatus),1 also known as “strawberry clipper,” can damage strawberry, blackberry, and related caneberries. Adults emerge in spring as temperatures rise above 60° F and initially feed on buds of strawberry and redbud. Some later move to blackberry, raspberry, and dewberry as buds begin to swell on these plants. Small holes are chewed in the buds and an egg inserted. The female then cuts the stem just below the bud, which often drops from the plant. Each female lays about 20–30 eggs, mostly in April and early May. The summer-generation adults appear in early summer and feed on pollen before moving to winter shelters. Strawberry bud weevil is a small (ca. 
inch) reddish-brown weevil.
PEPPER WEEVIL (Anthonomous eugenii)1 is a tropical species that occurs in parts of southern Texas, south Georgia, and Florida. Larvae tunnel the center of pepper fruit and feed on the seed mass. Adults are black weevils, about ⅛ inch, with a sparse covering of tan to gray hairs. Breeding may be continuous throughout the year, with fruit of nightshade an alternate host.
GRAPE CURCULIO (Craponius inaequalis)1 develops in the berries of grape grown in the southeastern states. Adults emerge in mid-June in Georgia and first feed on foliage, producing zigzag chewing wounds on leaves and petioles. They also puncture fruit to feed and lay eggs.
SUNFLOWER HEADCLIPPING WEEVIL (Haplorhynchites aeneus)2 clips the heads of developing sunflowers, coneflowers, and rudbeckia. The adults are shiny black to red-brown weevils, about ⅓ inch, and may first be observed on or very near developing flower heads in early July; females begin laying eggs a few weeks later. In the process of egg laying, females make a series of punctures in the stalk at the base of the flower head. This puncturing causes the stalk to break at the wound site and the head to hang from the stalk and wilt. Eggs are laid in the flower head and the grublike larvae develop while feeding on pollen and decaying tissues of the flower. In autumn they drop to the ground and burrow into the soil, where winter is spent. Pupation occurs in late spring of the following year. One generation is produced per year.
In the northern Great Plains, two species of small weevils develop in the seeds of sunflower: RED SUNFLOWER SEED WEEVIL (Smicronyx fulvus)1 and GRAY SUNFLOWER SEED WEEVIL (S. sordidus). Adults of red sunflower weevil move to the plants and feed first on the bracts of the developing head, then on pollen. When young seeds start to form, the weevils lay eggs inside them, and the grubs consume much of the seed interior while developing. In late summer they drop to the ground and dig a small soil cell, where they spend the winter in diapause. Pupation occurs the following year. Gray sunflower seed weevil is less damaging, as it lays fewer eggs and lays them earlier, beginning in the early to mid-bud stages.
COWPEA CURCULIO (Chalcodermus aeneus)1 develops within the seeds of several wild and cultivated plants, mostly legumes, but is particularly common in cowpea (Vigna spp.). Females chew into pods, lay an egg, and the grublike larvae then consume the developing seeds. Two generations are normally produced per year, and the overwintering stage is an adult. This insect is most abundant in the southeastern states but occurs north to New Jersey and into Kansas and Oklahoma.
A. Adult pepper weevil. ESTEBAN RODRÍGUEZ-LEYVA, POSGRADO EN FITOSANIDAD, COLEGIO DE POSTGRADUADOS, MONTECILLO, COURTESY OF UNIVERSITY OF CALIFORNIA STATEWIDE IPM PROGRAM
B. Pepper weevil larva and damage. ESTEBAN RODRÍGUEZ-LEYVA, POSGRADO EN FITOSANIDAD, COLEGIO DE POSTGRADUADOS, MONTECILLO, COURTESY OF UNIVERSITY OF CALIFORNIA STATEWIDE IPM PROGRAM
C. Grape curculio. NATASHA WRIGHT, COOK’S PEST CONTROL, BUGWOOD.ORG
D. Sunflower headclipping weevil. WHITNEY CRANSHAW
E. Damage produced by sunflower headclipping weevil. DAVID SHETLAR
F. Sunflower headclipping weevil making puncture wound in stem of sunflower. WHITNEY CRANSHAW
G. Larva of sunflower headclipping weevil in sunflower head. DAVID SHETLAR
H. Larva of the red sunflower seed weevil. FRANK PEAIRS, COLROADO STATE UNIVERSITY
I. Gray sunflower seed weevil. FRANK PEAIRS, COLORADO STATE UNIVERSITY
J. Red sunflower seed weevil. FRANK PEAIRS, COLORADO STATE UNIVERSITY
K. Cowpea curculio. CLEMSON UNIVERSITY–USDA COOPERATIVE EXTENSION SLIDE SERIES, BUGWOOD.ORG
L. Seeds damaged by cowpea curculio. GERALD HOLMES, CALIFORNIA POLYTECHNIC STATE UNIVERSITY AT SAN LUIS OBISPO, BUGWOOD.ORG
About 30 species of ACORN or NUT WEEVILS (Curculio spp.)1 develop in the seeds of oak and various nut trees. Adults are usually brown, about ¼ inch with a prominent snout, particularly on the female. The legless grubs develop in the nuts and are a favored food of squirrels. The most important species is PECAN WEEVIL (C. caryae), often the most serious pest of pecan grown in the southeastern U.S. Hickory is also a common host. Adults are active primarily from early August through September. Adults feeding on young nuts can cause abortion and shedding of damaged nuts.
Females lay small packets of 2–4 eggs inside the developing nut, and the larvae subsequently consume much of the nut meat over the next month. When feeding is completed, they drop to the ground and dig a small cell in the soil, where they remain for 1 or 2 years before pupating. During winter a mixture of adults and larvae may be found.
Other economically important species include LARGE CHESTNUT WEEVIL (Curculio caryatrypes) and SMALL CHESTNUT WEEVIL (C. sayi), both associated with chestnut, HAZELNUT WEEVIL (C. obtusus), and FILBERT WEEVIL (C. occidentis). HICKORY NUT CURCULIO (Conotrachelus hicoriae)1 is common in acorns and hickory nuts. Nuts of black walnut grown east of the Great Plains are infested by BLACK WALNUT CURCULIO (C. retentus). Wounds produced by adults that chew into the developing nuts in spring are a common cause of June drop. Larvae feed on the developing seeds.
The cones of many species of pines growing in western North America may be consumed by larvae of the WESTERN PINE CONE WEEVIL, Conophthorus ponderosae.1 In late spring or early summer, the adults tunnel into the base of second-year cones, excavating the center of the cone where they then lay eggs. The larvae feed on the developing seeds.
Adult of a western pine cone weevil. JAVIER MERCADO, USDA APHIS ITP, BUGWOOD.ORG
HOLLYHOCK WEEVIL (Rhopalapion longirostre)3 feeds on the seeds, buds, and leaves of hollyhock. Small feeding punctures in emerging leaves and petals give the plant a ragged appearance. The larvae consume the seeds of the plant. Hollyhock weevils spend the winter in the adult stage, either in protected areas around hollyhock or in seeds. They move to hollyhock plants in late spring and feed by chewing small holes in the buds of the plants. During this time the weevils are commonly observed mating, the female being identifiable by an extremely long “beak.” As flower buds form in June, the females chew deep pits in the buds and lay eggs. The grub stage of the insect feeds on the developing embryo of the seed. After feeding is completed, it pupates in the seed. Adults usually emerge in August and September, but some remain in the seeds, emerging the following spring. There is one generation per year.
Hollyhock weevil larva developing within seed. WHITNEY CRANSHAW
1 Coleoptera: Curculionidae
2 Coleoptera: Attelabidae
3 Coleoptera: Brentidae
B. Acorn weevil chewing into acorn. DAVID SHETLAR
C. Acorn weevil larva. STEVEN KATOVICH, USDA FOREST SERVICE, BUGWOOD.ORG
D. Pair of pecan weevils. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
E. Pecan weevil damage and larva. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
F. Chestnut weevil. DAVID SHETLAR
G. Larva of a western pine cone weevil. CANADIAN FOREST SERVICE, CANADIAN FOREST SERVICE, BUGWOOD.ORG
H. Cone damaged by western pine cone weevil. USDA FOREST SERVICE-OGDEN, USDA FOREST SERVICE, BUGWOOD.ORG
I. Pair of hollyhock weevils. WHITNEY CRANSHAW
The fruit flies (Tephritidae family) are a large group of flies that develop in fruits, stems, and leaves of plants. Adults have wings patterned with dark markings. Of the 290-odd North American species, only a few are seriously damaging to garden plants. Other flies that infest fruit include the gall flies (Cecidomyiidae) and the vinegar, or small fruit flies (Drosophilidae). The latter are particularly common on overripe fruit and occasionally are household pests.
APPLE MAGGOT (Rhagoletis pomonella)1
HOSTS Apple, pear, and large crabapples primarily. Late-season plum and cherry are infrequently infested, although some strains exist that prefer these hosts. Hawthorn is an important wild host in some western states.
DAMAGE Most damage results when the young maggots tunnel fruit, producing meandering brown trails that hasten rot. Egg-laying by the adults involves small puncture wounds (often called “stings”) to the fruit surface that cause dimple-like distortions.
DISTRIBUTION Primarily in apple-growing areas east of the Great Plains but has become established throughout much of North America, including isolated areas of the Pacific and Rocky Mountain states.
APPEARANCE Adults are picture-winged flies that have distinct black patterning on the wings. They are about ⅕ inch, generally black with a white spot on the back and a brown head. Larvae are cream-colored, legless maggots associated with the fruit. Pupae are pale yellowish brown, smooth, and somewhat seedlike.
LIFE HISTORY AND HABITS During winter, apple maggot is in the pupal stage, buried shallowly in soil near previously infested trees. Adults emerge in early summer, and females first feed for about 2 weeks on honeydew and other fluids in the vicinity of fruit trees. They then move to apple and begin to lay eggs, which they insert singly under the skin of the fruit. Peak egg-laying tends to occur in mid- to late July. Eggs hatch within a week. Larvae feed in the fruit for 3–4 weeks before dropping to the soil to pupate. One generation is produced per year, with the pupae remaining dormant until the following season.
RELATED FRUIT-INFESTING FLIES
CHERRY FRUIT FLY (Rhagoletis cingulata),1 also known as CHERRY MAGGOT, is an important pest of cherry in the north-central and northeastern U.S. and adjacent areas of southern Canada. Initial damage occurs when the adult female “stings” the cherry fruit with her ovipositor, producing small puncture wounds. Eggs are often laid in the punctures, and the immature maggots chew through the flesh of the fruit. Infested berries are misshapen, undersized, and mature prematurely.
Cherry fruit flies spend winter in the pupal stage around the base of previously infested trees. In late May, the flies begin to emerge and feed on fluids, including oozing sap from wounds made by puncturing fruit with their ovipositors. They feed for about 10 days before beginning to lay eggs. Females insert eggs under the skin of fruit for a period of 3 or 4 weeks. The immature maggots feed on the fruit, particularly the area around the pit. They become full grown in 2–3 weeks and drop to the ground to pupate. In most areas there is one generation per year.
BLACK CHERRY FRUIT FLY (R. fausta) has a similar life history and often occurs with cherry fruit fly in orchards. Pin cherry is the common wild host. WESTERN CHERRY FRUIT FLY (R. indifferens) is found in most of the western states and British Columbia where it develops on sweet, tart, and some wild-type cherries. Adults are present from June to August, most abundant often about the time of harvest.
B. Adult apple maggot. DAVID SHETLAR
C. Surface oviposition wound punctures made by adult apple maggot adults. WHITNEY CRANSHAW
D. Apple maggot larva in plum. WHITNEY CRANSHAW
E. Adult cherry maggot. TOM MURRAY
F. Mating pair of western cherry fruit flies. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
G. Western cherry fruit fly larva in cherry fruit. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
H. Western cherry fruit fly eggs laid under surface of cherry fruit. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
I. Western cherry fruit fly pupae. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
J. Western cherry fruit fly. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
WALNUT HUSK FLY (R. completa) is native to the south-central U.S. but has become widespread throughout western North America. The maggots tunnel the flesh of walnut husks, which stains the nuts and reduces value. Uncommonly this species also develops in late-ripening varieties of peach.
BLUEBERRY MAGGOT (R. mendax) is distributed throughout the eastern U.S. and Canada. Larvae develop in blueberry and huckleberry. This species is mostly a pest of commercial blueberry. In the southeastern U.S., adults emerge in late May and persist until late July, when their native host, deerberry, is fruiting. Females lay eggs singly in fruits, and larvae take about a month to develop. The pupae subsequently overwinter, sometimes for a second year before adults are produced.
Blueberry maggot larvae and damage. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
Adults of CURRANT FRUIT FLY (Euphantra canadensis)1 are generally yellowish with bright green eyes. Larvae develop in red and white currants and gooseberries. Eggs are inserted into the developing berries, and a red spot often develops at these oviposition wound sites. The larvae develop in the fruit, tunneling around the seeds, and become full grown about the time the fruit ripens. They then drop to the ground, dig into the soil, and pupate, the form in which they subsequently overwinter.
PEPPER MAGGOT (Zonosemata electa)1 is found in much of eastern North America and is native species thought to have originally been associated with horse nettle (Solanum carolinense). Cultivated peppers are damaged by adults when inserting eggs into the fruit surface, producing small dimpled wounds. More serious damage is caused by the larvae thatfeed on the flesh of the fruit core, producing brownish areas. Although widespread and fairly common, this species is rarely abundant and injuries are often overlooked. Only one generation is produced, and winter is spent as a pupa in the soil. Eggplant, tomatillo, and some wild nightshade weeds also host pepper maggot.
Pepper maggot larvae and damage. JUDE BOUCHER, UNIVERSITY OF CONNECTICUT
Feeding at the base of florets and minor damage to seeds are commonly produced by SUNFLOWER SEED MAGGOT (Neotephritis finalis).1 Many other aster family plants may also be infested by sunflower seed maggot. Tunneling into the receptacle at the base of the florets may occur with Gymnocarena diffusa,1 which often pupates at the base of the head.
There are several tropical species of fruit flies, not established in the continental U.S., that have significant potential to damage crops. These species are surveyed intensively to identify accidental introductions at an early stage. Efforts to eradicate the insect often follow detections. MEDITERRANEAN FRUIT FLY (Ceratitis capitata)1 has demonstrated ability to seriously damage a wide variety of fruit crops. It has been introduced, and subsequently eradicated, on several occasions in the continental U.S.; it is permanently established in Hawaii. ORIENTAL FRUIT FLY (Batrocera dorsalis)1 has been introduced into Florida but subsequently eradicated. MEXICAN FRUIT FLY (Anastrepha ludens)1 is presently known from some Texas counties near the Mexico border.
1 Diptera: Tephritidae
B. Walnut husk fly larvae. WHITNEY CRANSHAW
C. Adult of the blueberry maggot. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
D. Currant fruit fly larvae in gooseberry. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
E. Currant fruit fly pupae. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
F. Currant fruit fly adult. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
G. Adult pepper maggot. GARY STECK, FLORIDA DEPARTMENT OF AGRICULTURE AND CONSUMER SERVICES
H. Larva of Gymnocarena diffusa in the base of sunflower. FRANK PEAIRS, COLORADO STATE UNIVERSITY
I. Mediterranean fruit fly. SCOTT BAUER, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
J. Adult of Gymnocarena diffusa. WHITNEY CRANSHAW
K. Mexican fruit flies. JACK DYKINGA, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
L. Oriental fruit fly. SCOTT BAUER, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
SPOTTED-WING DROSOPHILA (Drosophila suzukii)1
HOSTS Spotted-wing drosophila is found in a wide variety of soft fruits, especially raspberries and blackberries. Other commonly grown fruit crops that can be damaged include strawberries, cherries, blueberries, grapes, peaches, plums, currants, and mulberries. Fruit of many ornamental plants such as yew, chokeberry, and some hawthorns are also hosts.
DAMAGE Damage is caused when the larvae feed on ripening fruit. In addition to insect feeding injuries, decay organisms (fungi, bacteria) often develop in the damaged fruit, further accelerating its softening. The very rapid fruit softening, combined with the presence of the larvae, often cause affected fruit to be discarded.
DISTRIBUTION Spotted-wing drosophila was first detected in North America in California in 2008. Within six years after initial discovery it had been reported from at least some areas within essentially every state and throughout much of southern Canada. Ultimately it is likely this insect will be present almost everywhere that susceptible fruit crops are grown in the U.S. and Canada.
APPEARANCE The adult spotted-wing drosophila is a small fly about ⅛ inch long. It is closely related and quite similar in appearance to many other Drosophila species, the common “vinegar flies” or “small fruit flies” associated with the yeasts of overripe fruit and other fermenting materials. The adult male is distinguishable by a small dark spot on the wings. Identification of the females requires close, microscopic examination of the ovipositor, which is substantially larger and more serrated than those “vinegar fly” Drosophila species that limit feeding to yeasts. The larvae of spotted-wing drosophila are tiny, cream-colored maggots found in the ripening fruit.
LIFE HISTORY AND HABITS Spotted-wing drosophila survives winter in the adult stage, with the flies remaining in a semidormant condition (diapause) during the cold months. During this time they may use many different sites for winter protection, but areas within the skins and husks of decaying fruit can be particularly important places where they will survive winter. With the return of warm weather in spring, the adults emerge and seek out honeydew, nectar, and oozing sap to sustain themselves.
As ripening fruits become available in late spring and early summer, egg laying resumes. When laying eggs, the female creates a small slit in fruit skin and inserts 1–3 eggs. This ovipositioining is repeated over a period of weeks, and a single female can lay up to around 350 eggs in her lifetime.
Depending on temperature, the eggs can hatch in 12–72 hours. The larvae then feed inside the fruit, becoming full grown in approximately 5–7 days. Larvae may then either remain inside the fruit to pupate or crawl away to pupate in a sheltered location around the base of the plant. Adults emerge from the pupae in about a week and feed for a brief period on nectar and honeydew before beginning to lay eggs for the next generation. During a year, numerous generations may be completed, perhaps a dozen or more in favorable climates, and peak populations tend to occur in later-maturing fruits (e.g., fall-bearing raspberries). Some continued development may occur during warm periods in autumn, when dropped fruit often serves as the food.
B. Spotted-wing drosophila adult on raspberry. HANNAH BURRACK, NORTH CAROLINA STATE UNIVERSITY, BUGWOOD.ORG
C. Adult male spotted-wing drosophila showing spot on wing. HANNAH BURRACK, NORTH CAROLINA STATE UNIVERSITY, BUGWOOD.ORG
D. Spotted-wing drosophila female showing prominent ovipositor. ERIC R. DAY, VIRGINIA POLYTECHNIC INSTITUTE AND STATE UNIVERSITY, BUGWOOD.ORG
E. Eggs of spotted-wing drosophila adult on strawberry. HANNAH BURRACK, NORTH CAROLINA STATE UNIVERSITY, BUGWOOD.ORG
F. Spotted-wing drosophila larvae in strawberry. HANNAH BURRACK, NORTH CAROLINA STATE UNIVERSITY, BUGWOOD.ORG
OTHER VINEGAR FLIES AND SMALL FRUIT FLIES1
HOSTS Almost any overripe fruit or fermenting materials that support growth of yeasts.
DAMAGE Vinegar flies are attracted to wounded or overripe fruits and vegetables that support fermenting yeasts. They do not cause direct injury to growing plants but can become serious pests of harvested produce as tunneling by the tiny maggots hastens fruit rotting. The small flies can also be annoying in kitchens, at beverage container recycling sites, around compost piles, and in worm beds where foods suitable for breeding are present.
DISTRIBUTION Throughout North America, common. Several species may be common, including Drosophila melanogaster, D. convexa, D. simulans, and D. funebris.
APPEARANCE Adults are tiny flies, about inch. The general body color is often yellowish or light brown, sometimes gray, and the eyes are large and reddish.
LIFE HISTORY AND HABITS Vinegar fly larvae develop on the yeasts that grow on well-ripened fruit and around wounds of plants. Food residues in beverage containers or garbage cans also commonly support growth of yeasts and serve as breeding sites. Adults lay eggs in these areas, and the young maggots can become fully grown in less than a week. Prior to pupation, the larvae migrate away from the food source and attach themselves tightly to plant stems, container walls, and other dry areas. Individual adults live about 4 weeks, with females capable of laying a few dozen eggs daily. Breeding is continuous throughout the warm season, and numerous generations are produced, with peak populations developing in late summer and early fall. Outdoors, vinegar flies go into dormancy during the cool season; indoors they may breed year-round.
The AFRICAN FIG FLY (Zaprionus indianus),1 like most of the vinegar flies, is considered a secondary pest, developing in overripe or damaged fruit, including fruit damaged by spotted-wing drosophila. It is larger than Drosophila species and also distinctly striped. African fig fly was first detected in Florida in 2005; since then it has spread extensively through North America.
1 Diptera: Drosophilidae
ROSE MIDGE (Dasineura rhodophaga)1
HOSTS Rose, particularly hybrid tea types.
DAMAGE The small maggot stage of rose midge feeds by making small slashes in developing plant tissues to suck the sap. Developing flower buds are distorted by this injury or may be killed, resulting in “blind” shoots on which no flower buds appear to form.
DISTRIBUTION Localized in many areas throughout North America.
APPEARANCE Adults are small, delicate flies, about 
inch and brown with a reddish tinge. Larvae are tiny maggots, creamy white to pale red and found about the base of buds.
LIFE HISTORY AND HABITS Rose midge overwinters in the pupal stage in the soil. The adult, an inconspicuous small fly, emerges in late spring, sometimes after the first crop of blossoms. Adults live only 1 or 2 days, but during this time the females lay numerous eggs under the sepals, in opening buds, and in elongating shoots. Hatching larvae slash plant tissues and feed on sap. Eggs hatch in a few days, and the larvae feed for about a week before dropping to the soil to pupate. The complete life cycle can take about 2 weeks, with numerous generations occurring in a growing season.
B. Vinegar fly adult laying eggs on overripe peach. WHITNEY CRANSHAW
C. Vinegar fly larvae developing in overripe banana. WHITNEY CRANSHAW
D. Vinegar fly pupae. WHITNEY CRANSHAW
E. Dead vinegar fly adults at bottom of glass of cider vinegar. WHITNEY CRANSHAW
F. The vinegar fly Drosophila melanogaster. JACK KALISCH, UNIVERSITY OF NEBRASKA
G. Adult of the African fruit fly. JEFFREY W. LOTZ, FLORIDA DEPARTMENT OF AGRICULTURE AND CONSUMER SERVICES, BUGWOOD.ORG
H. Damage to rose shoot bud by rose midge. ROBIN ROSETTA, OREGON STATE UNIVERSITY
I. Rose midge larva. ROBIN ROSETTA, OREGON STATE UNIVERSITY
J. Rose bud showing damage by rose midge. ROBIN ROSETTA, OREGON STATE UNIVERSITY
OTHER GALL MIDGES DAMAGING TO BUDS, FLOWERS, AND FRUIT
BLUEBERRY GALL MIDGE (Dasineura oxycoccana)1 infests blueberry and cranberry in the eastern U.S. and is particularly damaging to rabbiteye blueberry in the southeastern states. Larvae that develop in flower buds cause them to dry out and abort. The growing points on twigs may be destroyed, seriously reducing foliage growth. A generation can be completed in as little as 2 weeks, and multiple generations occur during the period of active growth of plants in late winter and spring.
CHOKECHERRY FRUITGALL MIDGE (Contarinia virginianae)1 distorts developing chokecherry fruits, causing them to enlarge and become hollow. Within this galled fruit the bright orange-red maggots develop and feed. Winter is spent in the pupal stage, around the base of previously infested chokecherries. Adults emerge in early spring, around the time of blossoming, and females lay eggs in the flowers. The larvae feed in the fruit until midsummer and then drop to the ground and pupate. There is one generation per year. A related species, HEMEROCALLIS GALL MIDGE (C. quinquenotata), has become established in parts of British Columbia. It is of European origin and distorts daylily flowers. Flowers of cypress are distorted by the CYPRESS FLOWER GALL MIDGE (Taxodiomyia cupressi).1
Several flies are associated with heads of sunflower. SUNFLOWER MIDGE (Contarinia schulzi) develop on buds and emerging flowers and can induce a gross clublike distortion of sunflower heads. Sunflower midge is particularly abundant in Minnesota, the Dakotas, and the Prairie Provinces, where it is sometimes limiting to sunflower production.
“CORNSILK FLIES”2 can be serious pests of sweet corn in Florida and some other areas in the southeastern U.S. This is a complex of small flies (ca. ⅙ inch) in the genera Chaetopsis and Euxesta that are most abundant in subtropical and tropical areas; C. massyla, E. stigmatias, and E. eluta are the most common pest species in Florida. Adults are a type of picture-winged fly, with banded wings and a body marked with metallic green or black.
These flies are active year-round and normally develop in a wide variety of damaged or culled fruit and vegetable matter. Silks of sweet corn, and sites on sweet corn wounded by other insects, can be highly attractive egg-laying sites for adults. Most damage occurs when larvae extensively damage the silks during pollination, resulting in poor kernel set. The larvae may also move into the ear tip and directly damage developing kernels.
Larvae of leafminer flies, such as the VEGETABLE LEAFMINER (Liriomyza sativae),3 normally develop within leaves but will sometimes tunnel under the surface of pods and fruit.
1 Diptera: Cecidomyiidae
2 Diptera: Otitidae
3 Diptera: Agromyzidae
A. Blueberry gall midge in flower bud of blueberry. BRIAN LITTLE, UNIVERSITY OF GEORGIA, BUGWOOD.ORG
B. Adult of the blueberry gall midge. BRIAN LITTLE, UNIVERSITY OF GEORGIA, BUGWOOD.ORG
C. Chokecherry fruit distorted by chokecherry fruitgall midge. WHITNEY CRANSHAW
D. Larvae of chokecherry fruitgall midge. WHITNEY CRANSHAW
E. Flowergalls produced by cypress flowergall midge. ALBERT (BUD) MAYFIELD, USDA FOREST SERVICE, BUGWOOD.ORG
F. Mining of surface of pea pod by a Liriomyza species of leafmining fly. WHITNEY CRANSHAW
Yellowjackets and hornets are members of the paper wasp family (Vespidae).1 These are social insects that produce colonies, with nests constructed of paperlike material. Although all can sting, most paper wasps are valuable insects that feed on many garden pests, and they are discussed in chapter 8 as biological control species. Those that can damage plants or interfere substantially with gardening are discussed below.
WESTERN YELLOWJACKET (Vespula pensylvanica)1
DAMAGE Yellowjackets are rarely directly damaging to plants, although they can become a problem when they feed on ripe fruit. Problems with stinging are most important, particularly as nests are often hidden and accidentally disturbed. Late in the season, serious nuisance problems occur as yellowjackets scavenge for meat and sweets. Western yellowjacket has omnivorous food habits and also feeds on many insects.
DISTRIBUTION Western yellowjacket is broadly distributed from the High Plains to the Pacific Coast.
APPEARANCE Adults are generally yellow with numerous black markings, including banding of the abdomen. They have a smooth body, without the numerous hairs found in bees.
LIFE HISTORY AND HABITS The only stage surviving winters is a fertilized female, the potential queen. These females become active during warm days in spring and actively search for suitable sites to initiate a nest. Belowground hollows, particularly abandoned rodent nests, are most commonly used. Other hollows such as those found behind walls are also used. A queen subsequently begins to build nest cells of paper which she creates from chewed plant fibers, often obtained from weathered wood. As these cells are created, she begins to lay eggs into them and subsequently feeds the developing larvae meat she collects. Living and dead insects, dead earthworms, and carrion may be used for food.
The first yellowjackets reared are considerably smaller and are infertile female workers. These begin to take over the functions of nest-building and rearing young. Colony size increases exponentially during the summer and by early fall may include one to several thousand individuals. Toward the end of the season, some larger rearing cells are built in which fertile females are produced. At this time males also begin to be produced and mating occurs outside the nests.
At the end of the season, rearing slows and colonies begin to break up. All workers, the founding queen, and males die, with only new fertilized females surviving to disperse to find shelter in various protected sites. The old nests are abandoned and not reused.
OTHER YELLOWJACKETS AND HORNETS
Thirteen Vespula species occur in North America and some can be common species. EASTERN YELLOWJACKET (V. maculifrons) occurs broadly across areas east of the Great Plains. GERMAN YELLOWJACKET (V. germanica) is mostly restricted to the northeastern U.S. The PRAIRIE YELLOWJACKET (V. flavipilosa) occurs in the Midwest and northeast, and the SOUTHERN YELLOWJACKET (V. squamosa) in the southeast. The last occasionally produces colonies that survive a winter and may become very large. All these yellowjackets are primarily predators early in the season when rearing young, then increasingly switch to high-carbohydrate foods such as nectar and honeydew when new potential queens and males are being produced.
B. Western yellowjacket feeding on fried chicken. WHITNEY CRANSHAW
C. Belowground paper nest of the western yellowjacket. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
D. Western yellowjacket queen gnawing on weathered wood for nest construction material. WHITNEY CRANSHAW
E. Eastern yellowjacket. JIM KALISCH, UNIVERSITY OF NEBRASKA
F. Nest entrance of an eastern yellowjacket colony. JIM KALISCH, UNIVERSITY OF NEBRASKA
G. German yellowjacket queen. DAVID SHETLAR
H. Early season nest of a German yellowjacket. DAVID SHETLAR
I. German yellowjacket larvae and capped cells of pupae. DAVID SHETLAR
J. Partially excavated eastern yellowjacket nest. DAVID SHETLAR
K. A deconstructed late season nest of German yellowjacket. DAVID SHETLAR
L. German yellowjacket male. DAVID SHETLAR
BALDFACED HORNET (Dolichovespula maculata)1 and the closely related AERIAL YELLOWJACKET (D. arenaria) produce large, aboveground paper nests in trees, dense shrubbery, and sheltered areas beneath overhanging roofs. Although these species are capable of stinging, their conspicuous nests greatly lessen the likelihood of accidental disturbance. Also, as their diets consist almost entirely of live insects, they do not scavenge as do many yellowjackets. In late summer they will collect honeydew, feed on nectar and pollen, and sometimes also chew on well-ripened fruit.
EUROPEAN HORNET (Vespa crabro germana)1 is a very large wasp that constructs its paper nests in a manner similar to yellowjackets: in hollows of trees or behind walls and in holes in the ground. It sometimes does considerable damage in late summer to certain trees and shrubs by chewing bark, which it uses to form its paper nest. Lilac, boxwood, birch, willow, mountain-ash, and poplar are among the plants most commonly damaged. Affected twigs and branches often wilt permanently and may die back following these injuries. The European hornet is presently known from most eastern and midwestern states and parts of southern Ontario. The European hornet is often mistaken for the ASIAN GIANT HORNET (Vespa mandarinia) which is a larger and more aggressive species that has not been established in North America.
European hornet feeding on ripe fruit. DAVID SHETLAR
Distorted terminal growth of chestnut produced by Asian chestnut gall wasp. DAVID SHETLAR
GALL WASPS AFFECTING NUTS
ORIENTAL CHESTNUT GALL WASP (Dryocosumus kuriphilus)2 produces galls in the shoot tips, leaves, and catkins of chestnut. Shoot growth and nut production can be severely reduced by infestations. This insect was first detected in North America in 1974 and has since spread to most of the Mid-Atlantic region and west to Tennessee and Ohio.
Several native gall wasps develop in acorns of oak. Callirhytis fructuosa2 and the PIP GALL WASP (C. operator) are among the common species. Both develop in acorns of red oak.
1 Hymenoptera: Vespidae
2 Hymenoptera: Cynipidae
B. Baldfaced hornet chewing on wood. JIM KALISCH, UNIVERSITY OF NEBRASKA
C. Baldface hornet nest cut away to show internal construction. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
D. Aerial yellowjacket. WHITNEY CRANSHAW
E. Bark chewing by European hornet. JIM BAKER, NORTH CAROLINA STATE UNIVERSITY, BUGWOOD.ORG
F. Adult of the Asian chestnut gall wasp. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
G. Larvae of the Asian chestnut gall wasp. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
H. Adults of the Asian chestnut gall wasp in gall. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
I. Galls produced in acorn by Callirhytis fruticosa. LARRY R. BARBER, USDA FOREST SERVICE, BUGWOOD.ORG
J. External evidence of acorn damaged by the gall wasp Callirhytis operator. LARRY R. BARBER, USDA FOREST SERVICE, BUGWOOD.ORG
WESTERN FLOWER THRIPS (Frankliniella occidentalis)1
HOSTS A wide range of herbaceous plants, including both broadleafed and grasses.
DAMAGE Scarring injury to flowers is the most common concern to gardeners. In the landscape, injuries are usually minor, but occasionally they seriously blemish or distort flowers. Feeding injuries to vegetables typically involve slight scarring. Cloudy “pansy” or “halo” spots may be produced on fruit around egg-laying puncture wounds. Western flower thrips is also a highly efficient vector of viruses in the tospovirus group, which can produce the plant diseases tomato spotted wilt, impatiens necrotic spot, and iris yellow spot.
DISTRIBUTION Formerly limited largely to western states but now found throughout most of North America. It is particularly common in the southern half of the U.S., where it can be a major pest of vegetable crops. Western flower thrips is one of the most important greenhouse pests throughout the continent.
APPEARANCE Difficult to distinguish from most common thrips on leaves and flowers without high magnification. Adults are about 
inch, slender, and range from yellow to brown. Nymphs are yellow.
LIFE HISTORY AND HABITS Flower thrips are moderately cold hardy and likely survive winter outdoors in much of the southern half of the U.S. In warmest areas, and in greenhouses, reproduction may be continuous as long as conditions permit. Elsewhere flower thrips may winter under leaf debris or other protected sites. Adults feed on pollen in addition to plant sap.
Females insert eggs into emerging leaves, buds, and flowers. Eggs hatch in about 5–7 days, but this period can be extended considerably with cool temperatures. Subsequently there are two larval (nymphal) stages that actively feed and produce most of the physical plant injuries. Depending on temperature, the larval stages are normally completed in 1–2 weeks. Two nonfeeding stages (prepupa, pupa) then occur, usually in soil. Another week or so is required for completion of these stages, after which the adult is present to repeat the cycle. Multiple generations occur outdoors, and breeding may be continuous in greenhouses. Mass movements frequently occur in summer following the decline of flowers and other alternate hosts.
Generalized life cycle of a thrips. ILLUSTRATION COURTESY OF UNIVERSITY OF CALIFORNIA STATEWIDE IPM PROGRAM
RELATED SPECIES
FLOWER THRIPS (Frankliniella tritici) is a native insect, found primarily in eastern North America. Its habits and hosts are similar to those of western flower thrips, but it has been less important as a vector of tomato spotted wilt and impatiens necrotic spot viruses. TOBACCO THRIPS (F. fusca) is common east of the Rockies and particularly abundant in the southeastern U.S. It develops on grasses and many vegetables but is primarily a pest of field crops such as cotton, tobacco, alfalfa, and peanut. Tobacco thrips can also transmit tomato spotted wilt virus.
Scarring of flowers and developing seeds or fruit also occurs with other species of thrips. Among these are GLADIOLUS THRIPS (Thrips simplex)1 on gladiolus; MELON THRIPS (T. palmi) on a variety of fruiting vegetables; CITRUS THRIPS (Scirtothrips citri)1 on certain citrus; and AVOCADO THRIPS (S. perseae) on avocado.
1 Thysanoptera: Thripidae
B. Oviposition wound in snow pea produced by western flower thrips. WHITNEY CRANSHAW
C. Nymph of a flower thrips. BRUCE WATT, UNIVERSITY OF MAINE, BUGWOOD.ORG
D. Side view of a thrips showing blade-lake ovipositor at hind end. ALTON N. SPARKS JR., UNIVERSITY OF GEORGIA, BUGWOOD.ORG
E. Oviposition wounds in tomato produced by western flower thrips. WHITNEY CRANSHAW
F. Western flower thrips injury to English daisy. WHITNEY CRANSHAW
G. Western flower thrips injury to sweet pea. WHITNEY CRANSHAW
H. Surface scarring of peach by thrips feeding. HAROLD LARSEN, COLORADO STATE UNIVERSITY
I. Galdiolus thrips injury to blossom. WHITNEY CRANSHAW
J. Surface scarring of avocado by avocado thrips. MARK S. HODDLE, UNIVERSITY OF CALIFORNIA-RIVERSIDE, BUGWOOD.ORG
K. Citrus thrips injury to orange. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA STATEWIDE IPM PROGRAM
TARNISHED PLANT BUG (Lygus lineolaris)1
HOSTS Mostly herbaceous garden plants and weeds, particularly composites and legumes. Peach, apricot, and strawberry are among the fruit crops most commonly damaged.
DAMAGE Tarnished plant bug feeds on developing leaves, fruits, and flowers, killing the areas around the feeding site. This can cause abortion of young flowers, developing seeds, or fruit. Death of buds may lead to abnormally bushy growth. Older tissues may continue to grow but be deformed. Catface injuries to fruit are among the commonly observed distortions caused by tarnished plant bug feeding.
DISTRIBUTION Throughout North America.
APPEARANCE Adults are generally oval, about twice as long as wide, and about ¼ inch long. They are generally brown with some yellow and reddish markings. Color tends to darken with age. Nymphs are more rounded in form and usually yellowish green to dark green, often with dark spotting.
LIFE HISTORY AND HABITS Winter is spent in the adult stage under the cover of piled leaves, bark cracks, or other sheltered sites. Adults emerge and become active in early spring, feeding on buds of trees and shrubs. Most then move to various weeds and other plants, and females insert eggs into the stems, leaves, and buds of these plants. The young hatch, feed, and develop on these plants, becoming full grown in about a month. Several generations are produced during the year.
Tarnished plant bug is an omnivore that also feeds on aphids and other small, soft-bodied insects, effecting some biological control of these pests that is considered beneficial.
RELATED SPECIES
Thirty-four species of Lygus occur in North America, and most have similar life histories. PALE LEGUME BUG (L. elisus) is a common and damaging species found west of the Mississippi. Pale legume bug has a broad host range and, despite its name, is most commonly associated with cabbage family plants. WESTERN TARNISHED PLANT BUG (L. hesperus) is largely restricted to areas west of the Rockies. It has a wide host range that includes vegetables, seed crops, alfalfa, and some fruit.
CAMPYLOMMA BUG (Campylomma verbasci),1 also known as MULLEIN BUG, is found widely over southern Canada and northern U.S. It is sometimes considered a tree-fruit pest, particularly of apple; first-generation nymphs feed on developing fruit, causing abortion or corky warts to develop on the fruit surface. Later in the season, campylomma bug is beneficial to orchardists as a predator of aphids, mites, and pear psylla. Summer activity occurs primarily on various weeds, particularly common mullein. Winter is spent as eggs inserted into apple and pear twigs.
The genus Lopidea1 includes some relatively small (ca. ⅙, inch), brightly colored plant bugs, often with prominent scarlet markings. PHLOX PLANT BUG (L. davisi) damages the buds and distorts the flowers of phlox in the midwestern U.S. Feeding by L. confluenta is associated with bud abortion on daylily and iris in the southern U.S.
The “tomato bug” Engytatus modestus1 feeds on the young shoots, buds, and developing flowers of tomato. Feeding wounds, in the form of small punctures, tend to be concentrated at specific sites on stems, producing cumulative wounding that causes flowers and fruit to drop. The tomato bug has a wide host range, but tomato is the only plant that may sustain serious damage. The tomato bug is present primarily in the southwestern U.S., from Texas to southern California, but has been found in Hawaii and some eastern states.
1 Hemiptera: Miridae
B. Tarnished plant bug injury to flower petals. WHITNEY CRANSHAW
C. Pale legume bug. WHITNEY CRANSHAW
D. Western tarnished plant bug. WHITNEY CRANSHAW
E. Tarnished plant bug nymph. SCOTT BAUER, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
F. Tarnished plant bug nymph on strawberry. JEFF HAHN, UNIVERSITY OF MINNESOTA
G. Plant bug feeding wound in young pear. WHITNEY CRANSHAW
H. Catfacing injuries to pear resulting from plant bug wounding. WHITNEY CRANSHAW
I. Campyloma bug. BRADLEY HIGBEE, PARAMOUNT FARMING, BUGWOOD.ORG
J. Phlox plant bugs. JIM KALISCH, UNIVERSITY OF NEBRASKA
K. Adult of the “tomato bug” Engytatus modestus. WHITNEY CRANSHAW
L. Nymph of the “tomato bug” Engytatus modestus. WHITNEY CRANSHAW
BROWN MARMORATED STINK BUG (Halyomorpha halys)1
HOSTS A very wide range of plants can be fed on and damaged by brown marmorated stink bug, including most tree fruits, various legumes, sweet corn, caneberries, and peppers. Feeding can occur on many types of trees and shrubs, with tree-of-heaven (Ailanthus altissima) and princess tree (Paulownia tomentosa) being particularly favored species. Greatest damage to crops has occurred to apples and pears.
DAMAGE When feeding, brown marmorated stink bugs kill the tissues at the feeding site. This can produce a range of effects depending on when and where feeding occurs. The most commonly seen damage is on developing fruit, where feeding results in sunken “catfacing” injuries. Feeding on very young fruits or blossom may cause abortion of these plant parts. Feeding on limbs of trees and shrubs can produce wounds under bark that often weep. However, brown marmorated stink bugs are often most notorious for their habit of commonly using buildings for winter shelter. Very large numbers of these insects may collect indoors, particularly in upper stories, and they can secrete an unpleasant odor when disturbed. Although they do not reproduce during the period indoors, being in a semidormant state (diapause), they may periodically become active and move about, particularly during warm periods.
DISTRIBUTION Brown marmorated stink bug was first detected in Pennsylvania in 1998 and since that time has developed into an important pest throughout the Mid-Atlantic region; however, it is very easily and commonly transported by humans. Established, reproducing populations are present over a wide area of the eastern U.S. Detections of this insect have also been reported from most of the Continental U.S., although in some areas it appears unable to establish or thrive.
APPEARANCE The adult insect is about ¾ inch long and of the broad body form typical of stink bugs. It is generally brown with some marbling (marmoration) of the surface. Patches of small punctures on the front half of the body and a series of light markings edge the back of the body. The most useful characteristic to distinguish this from other brown-colored stink bugs (and there are many) is the presence of white banding on the antennae.
Immature stages are smaller, a bit more rounded in body form than adults, and lack fully developed wings. Overall coloration is gray to brown, but the abdomen is generally lighter-colored with several darker bands.
LIFE HISTORY AND HABITS Adults usually emerge from overwintering sites (including buildings) in mid- to late April. They first move to trees to feed on developing seeds, fruits, and emerging leaves and stems.
Brown marmorated stink bugs on peach. GARY BERNON, USDA APHIS, BUGWOOD.ORG
After feeding for about 2 weeks, the overwintered adults mate and females begin to lay eggs. Eggs are laid in the form of a mass on the underside of leaves. Typical egg masses have 20–30 light yellow to yellow-red eggs, with the top ridged with fine spines. A series of egg masses, laid at approximately weekly intervals, may be produced through August.
At egg hatch, the first-instar nymphs are tiny, a mixture of black and red, and they remain clustered around the egg mass for a couple of days. After molting again, later-stage nymphs take on a more generally gray to brown color and disperse throughout the plant, although they will sometimes cluster in protected areas of the plant, such as leaf folds. They become full grown about a month after egg hatch, and the adults continue to feed throughout the growing season. In late summer they begin to cease feeding and move to overwintering sites. One generation per year is normally produced in the mid-Atlantic region, although additional generations are possible in warmer climates.
B. Brown marmorated stink bug nymphs. DAVID SHETLAR
C. Brown marmorated stink bug egg mass. DAVID SHETLAR
D. Rough stink bug. WHITNEY CRANSHAW
E. Southern green stink bug. RUSS OTTENS, UNIVERSITY OF GEORGIA
F. Southern green stink bug nymph. RUSS OTTENS, UNIVERSITY OF GEORGIA
OTHER STINK BUGS THAT FEED ON FLOWERS, FRUIT, AND SEEDS
ROUGH STINK BUGS (Brochymena quadripustulata, B. affinis, B. sulcata, others)1 are dark brown or gray with a slightly scalloped body form. They blend in well with bark and are most commonly encountered on trees. Rough stink bugs are primarily predators of insects but sometimes feed on leaves. They are among the stink bugs with general appearance similar to the brown marmorated stink bug but can be distinguished by lack of banding on the antennae.
SOUTHERN GREEN STINK BUG (Nezara viridula)1 is found in the southeastern U.S., where it is considered an important pest of vegetables and field and orchard crops. Legumes and crucifers are particularly favored, but the host range is wide. Feeding on buds and blossoms causes them to wither and die. Feeding punctures in fruit cause deformed growth, and seeds may be shriveled. Adults are about ½ inch long and dull green. The young nymphs are pinkish but turn increasingly green with age. Development is usually completed in 65–70 days, and four generations are typically produced. The adults go dormant with decreasing day length.
Stink bug damage to pecan. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
Damage to interior of cotton boll due to stink bug feeding wounds. RONALD SMITH, AUBURN UNIVERSITY, BUGWOOD.ORG
Stink bug damage to tomato. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA IPM PROGRAM
GREEN STINK BUG (Acrosternum hilare)1 is broadly distributed throughout most of the U.S. and southern Canada. It is similar in appearance to southern green stink bug but considered much less damaging. Hosts include most vegetables as well as many fruit trees. One or two generations are produced, depending on temperature and location.
Stink bugs of the genus Chlorochroa1 are primarily western in distribution. They are most commonly known to damage small grains but will feed on vegetables and certain flowers. Most are green, but some may be quite dark with purplish or reddish coloration. Common species associated with plant injuries include SAY STINK BUG (C. sayi), UHLER STINK BUG (C. uhleri), and CONCHUELA (C. ligata). Occasionally these stink bugs will mass on the exterior of buildings, but they do not invade homes during winter.
Euschistus1 stink bugs are gray or brown and somewhat more angular in form. A few are minor pests of fruits and buds, including BROWN STINK BUG (E. servus), CONSPERSE STINK BUG (E. conspersus), and ONESPOTTED STINK BUG (E. variolarius).
Stink bugs of the genus Triyanta1 are generally green but may have colored markings, particularly a rosy border along the scutellum, behind the head. Thyanta custator (REDSHOULDERED STINK BUG) and T. pallidovirens are the most common species in yards and gardens, widely distributed in North America. Like many other stink bugs, they feed on fruit and seeds of a wide variety of plants but rarely cause significant injury.
Cosmopepla lintneriana (TWICESTABBED STINK BUG) is a generally black-colored stink bug with bold red markings that is widely distributed in North America. They are generalist feeders on seeds of many common garden plants, including thistles, Echinacea, mints, and goldenrod. Five other Cosmopepla species, with more limited distributions, also occur in the U.S.
1 Hemiptera: Pentatomidae
A. Green stink bug. SUSAN ELLIS, BUGWOOD.ORG
B. Green stink bug nymph. SUSAN ELLIS, BUGWOOD.ORG
C. Conchuela stink bug. WHITNEY CRANSHAW
D. Nymph of the conchuela stink bug. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
E. Egg mass of Uhler stink bug. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
F. Say stink bug. JIM KALISCH, UNIVERSITY OF NEBRASKA
G. Brown stink bug. RUSS OTTENS, UNIVERSITY OF GEORGIA
H. Brown stink bug nymph. RUSS OTTENS, UNIVERSITY OF GEORGIA
I. Twicestabbed stink bugs. DAVID SHETLAR
J. Redshouldered stink bug. WHITNEY CRANSHAW
BOXELDER BUG (Boisea trivittata)1
HOSTS Boxelder and caddo maple, primarily. Silver and red maples are other hosts.
DAMAGE Nymphs and adults usually feed on sap from seeds, flowers, and leaves but cause little damage to trees. Occasionally they feed on developing fruits, such as apples, and can produce puckered catface injuries to these plants. The major “damage” from these insects is their appearance in nuisance numbers on the windows and porches of homes in cooler months of the year. Their presence is most commonly noted on sunny days in fall and spring.
DISTRIBUTION Throughout North America, east of Nevada.
APPEARANCE Adult stages are brownish black, about ½ inch long, with 3 red lines on the head and a bright red abdomen beneath the wings. The nymphs are somewhat more oval in form and predominantly red except where the black wing pads are developing.
LIFE HISTORY AND HABITS Boxelder bugs overwinter in the adult stage in protected sites, often including homes. They emerge in mid-spring and lay groups of rusty red eggs near deposits of dropped seeds of boxelder, other maples, and occasionally ash. The first-generation nymphs feed on these seeds, various low-growing plants, and recently dead insects. They may also be cannibalistic, feeding on other nymphs in the process of molting. They become full grown in early summer.
A second generation occurs in late summer. Eggs are laid almost entirely on boxelder, particularly on seeds produced by female trees. The nymphs often develop on these seeds into October if weather permits. After frosts, boxelder bugs move to winter shelter, during which time homes are invaded. Boxelder bugs can move hundreds of yards from boxelder trees.
RELATED AND SIMILAR SPECIES
In the western states and British Columbia, WESTERN BOXELDER BUG (Boisea rubrolineata)1 is present but not nearly as significant a nuisance pest as boxelder bug. Feeding on developing tree fruits causes pitting and catfacing injuries.
Boxelder bug eggs. WHITNEY CRANSHAW
Another common black-and-red bug found in western North America and often mistaken for boxelder bug is SMALL MILKWEED BUG (Lygaeus kalmii).2 It develops on seeds of a wide variety of plants, including many weeds, and is not considered a pest. A closely related species, L. angustomariginatus, is common in eastern North America. The larger and more brightly colored LARGE MILKWEED BUG (Oncopeltus fasciatus)2 is a specialist of milkweeds and feeds on the seeds.
Small milkweed bugs. WHITNEY CRANSHAW
B. Boxelder bug nymph feeding on developing cherry fruit. WHITNEY CRANSHAW
C. Boxelder bugs massing in early fall. WHITNEY CRANSHAW
D. Mixed stages of boxelder bugs on boxelder trunk. WHITNEY CRANSHAW
E. Western boxelder bug. DAVID SHETLAR
F. Large milkweed bug. DAVID SHETLAR
G. Large milkweed bugs massed on milkweed pod. DAVID SHETLAR
Jadera haematoloma,1 known variously as the RED-SHOULDERED BUG, “goldenrain-tree bug,” and “soapberry bug,” develops on the seeds of goldenrain tree and other soapberries. Noticeable numbers of the insects may be observed massing in the vicinity of host trees in late summer, including walls of buildings, but they do not migrate into buildings for overwintering, unlike boxelder bugs. It is distributed primarily in the southeastern states but is found in other areas in association with its host.
In the southeastern states, HIBISCUS BUG (Niesthrea louisianica)1 may be common on hibiscus and rose of Sharon. Eggs are laid in masses on leaves, and the young develop by feeding on buds and seeds. Little damage is produced, but the brightly colored, orange-and-black bugs may become sufficiently abundant to attract attention. Usually one and occasionally two generations are produced annually.
More than a dozen species of seed-feeding bugs in the genus Arhyssus1 are present in North America. Many can be commonly found on flowers, although they rarely attract attention, being of moderate size (ca. ⅓ inch), and usually a general brown or greenish coloration. Some are specialists in certain types of plants while others apparently feed on seeds of many plants, including several common weeds found in gardens. None appear to cause significant plant damage. A few species are more important as nuisance invaders of homes in late summer and fall, including A. crassus (“weed bug”) in parts of California and A. lateralis in Colorado, apparently feed on seeds of many plants, especially perennials and annual flowers.
A great many other seed bugs are associated with seeds of plants that grow in yards and gardens. Various Nysius2 species, often collectively referred to as “FALSE CHINCH BUGS,” can be extremely common insects in areas of the western U.S. and Prairie Provinces, where they may be seen massing in very large numbers on seed heads. Mustard family plants are favored, but they may also occur on many common weeds, including kochia and pigweeds. Pigweeds, amaranth, and several weeds host various ASH-GRAY LEAF BUGS (Parapiesma spp.)3 which may mass on seed heads and damage seed production.
Seed-feeding bugs are also associated with many shade trees but are rarely observed and cause no noticeable injuries to plants. SYCAMORE SEED HEAD BUG (Belonochilus numenius)2 is sometimes abundant enough to attract attention in masses near sycamore trees, and the BIRCH CATKIN BUG (Kleidocerys resedae)2 is a nuisance invader-type species that will enter homes in autumn.
1 Hemiptera: Rhopalidae
2 Hemiptera: Lygaeidae
3 Hemiptera: Piesmatidae
False chinch bugs massed on seed pod. WHITNEY CRANSHAW
B. Mixed stages of red-shouldered bugs. BOB HAMMON, COLORADO STATE UNIVERSITY
C. An Arhyssus species of seed feeding bug. WHITNEY CRANSHAW
D. A pair of ash-gray leaf bugs. DAVID SHETLAR
E. Birch catkin bug. TOM MURRAY
WESTERN CONIFER-SEED BUG (Leptoglossus occidentalis)1
HOSTS Seeds within cones of various conifers, particularly pines, spruces, and Douglas-fir. Less commonly, western conifer-seed bugs will feed on seeds and developing fruit of many trees and shrubs.
DAMAGE Western conifer-seed bug feeds largely on developing seeds within the cones of pines and other conifers. Injured seeds fail to develop normally, and seed production can be greatly reduced. The cones may also ooze sap from the feeding puncture wounds. In yards and gardens, western conifer-seed bugs will occasionally feed on developing seeds and fruit of many plants, and they can be one of a number of bugs (e.g., various stink bugs, leaffooted bugs, plant bugs, boxelder bugs) that create catfacing injuries to fruit.
Western conifer-seed bug is most familiar as an increasingly encountered nuisance invader of homes in fall. It is essentially harmless and does not bite, although its rather bizarre appearance often causes alarm. This insect may also produce a slightly pine-scented odor when disturbed.
DISTRIBUTION Western conifer-seed bug is native to western North America; however, it has seen broad extensions of its range in recent decades. It is now commonly found throughout most of the midwestern and eastern U.S. Furthermore, it has also been accidentally introduced into Europe and is presently spreading through the continent.
APPEARANCE Western conifer-seed bug is a member of the leaffooted bug family Coreidae and has the typical feature of this family of long hind legs with a flattened area near the tip. Adults are about ¾ inch long, generally orange-brown, with some black markings on the back. Young nymphs are light orange but increasingly darken in later stages.
LIFE HISTORY AND HABITS Winter is spent in the adult stage, under debris, loose bark, abandoned bird nests, or other protected sites, including areas behind building walls. Adults emerge during warm days in spring and feed on young cones and flowers. Mating occurs in spring, and shortly afterward, females begin to lay eggs. Eggs are laid in small masses, usually end-to-end, on needles or cones. Egg laying continues over several months, and one female may lay a total of 100–200 eggs.
Eggs hatch in about 10 days and the nymphs feed on needles and developing seeds of the host plant. The nymphs develop through five instars, typically taking a little more than a month to complete. A second generation is likely produced in warmer areas, but one generation per year is normal in the northern parts of the range. Since egg laying is staggered and multiple generations can occur, all stages may be present on plants through much of the summer. As weather cools and day length shortens, adults move to overwintering sites and prepare to go into winter dormancy. During this time they may be active during warm periods, but reproduction is suspended and activity slows.
RELATED SPECIES
Twelve species of Leptoglossus occur north of Mexico, and several of these are associated with plant injuries. LEAFFOOTED BUG (L. phyllopus) is common in the eastern half of the U.S. and is also found in southern California. Its most common host in Florida is thistle, and in Kansas it is common on yucca. It may also occur on tender shoots, buds, and fruits of a wide variety of plants and incidentally damage some fruit and nut crops. L. clypealis is a western species, occasionally damaging to nut crops but usually associated with native plants such as yucca. LEAFFOOTED PINE SEED BUG (L. corculus) is commonly damaging to pine seeds, and L. fulvicornis can be common on magnolia fruit in the southeastern states. In California, L. zonatus is reported to damage fruit of pomegranate, pistachio, almonds, and tomatoes.
B. Eggs of western conifer-seed bug. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
C. Western conifer-seed bug nymph. KEN GRAY COLLECTION, OREGON STATE UNIVERSITY
D. A leaffooted bug Leptoglossus phyllopus. DAVID CAPPAERT, BUGWOOD.ORG
E. Leaffooted bugs feeding on fruit. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
F. Leaffooted bug nymphs. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
G. A western species of leaffooted bug, Leptoglossus clypealis. WHITNEY CRANSHAW
H. Nymphs of the leaffooted bug Leptoglossus fulvicornis. LACY L. HYCHE, AUBURN UNIVERSITY, BUGWOOD.ORG
I. Adult and last-instar nymph of the leaffooted bug Leptoglossus fulvicornis. LACY L. HYCHE, AUBURN UNIVERSITY, BUGWOOD.ORG
J. Catfacing of peach caused by feeding injury produced by a leaffooted bug. CLEMSON UNIVERSITY–USDA COOPERATIVE EXTENSION SLIDE SERIES, BUGWOOD.ORG
Euthochtha galeator1 is another common leaffooted bug found feeding on buds, seeds, and terminal growth of various trees and shrubs in the eastern U.S. The feeding of SQUASH BUG (Anasa tristis)1 on fruits of squash produces sunken wounds that result in scabby areas on the surface and may provide entry wounds for decay organisms.
Scabby patches on squash fruit result from reaction to squash bug feeding wounds. WHITNEY CRANSHAW
The largest members of the leaffooted bug family in the U.S. are in the genera Acanthocephala and Mozena.1 None are pests of garden plants, but their large size can attract attention. Acanthocephala declivis is found over a wide area of the southeastern U.S., where it is associated with oak. Acanthocephala femorata, sometimes known as the “Florida leaffooted bug” is also found in the southern states but occurs in Texas and Mexico. It is sometimes damaging to citrus fruit and roses. Acanthocephala terminalis is the most northern-ranging member of the genus.
1 Hemiptera: Coreidae
SCALES AND MEALYBUGS ASSOCIATED WITH FRUIT INJURIES
A few types of armored scales will colonize the surface of developing fruit. This habit is best known with SAN JOSE SCALE (Quadraspidiotus perniciosus),1 which can cause serious fruit blemishing to apple, pear, and plum. Surface pitting and a reddish ring often develop around the feeding site. CALIFORNIA RED SCALE (Aonidiella aurantii)1 and YELLOW SCALE (A. citrina) occur in California, where they can develop on the surface of citrus fruit.
California red scale infested orange fruit. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA STATEWIDE IPM PROGRAM
Some species of mealybug can damage fruit. Infestations of CITRUS MEALYBUG (Planococcus citri)2 on stems can cause abortion of flowers and fruit as a result of toxins introduced with the saliva. In high populations they may also colonize fruit. Clusters of developing grape can also be infested by GRAPE MEALYBUG (Pseudococcus maritimus)2 and OBSCURE MEALYBUG (P. viburni). A great many other insects associated with fruit crops, notably certain aphids, psyllids, soft scales, and mealybugs, can indirectly damage fruit through their excreted honeydew and the sooty molds that subsequently grow on honeydew-contaminated surfaces.
1 Hemiptera: Diaspididae
2 Hemiptera: Pseudococcidae
A. The leaffooted bug Euthochtha galeator. JOHNNY N. DELL, BUGWOOD.ORG
B. Squash bug feeding on pumpkin fruit. WHITNEY CRANSHAW
C. The leaffooted bug Acanthocephala declivis. WHITNEY CRANSHAW
D. The leaffooted bug Acanthocephala terminalis. DAVID SHETLAR
E. San Jose scale on apple. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA STATEWIDE IPM PROGRAM
F. Close-up of San Jose scale. DAVID SHETLAR
G. California red scale. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA STATEWIDE IPM PROGRAM
H. Citrus mealybug infesting orange fruit. JIM KALISCH, UNIVERSITY OF NEBRASKA
I. Grape mealybugs infesting cluster of grapes. HAROLD J. LARSEN, COLORADO STATE UNIVERSITY
J. Sooty mold growing on honeydew collected on surface of citrus fruit. DON FERRIN, LOUISIANA STATE UNIVERSITY AGRICULTURAL CENTER, BUGWOOD.ORG
ERIOPHYID MITES THAT DAMAGE FRUITS AND FLOWERS
Eriophyid mites are minute mites that can produce a range of plant disorders. Many produce various types of galls on leaves and buds, discussed on page 328. Others, known as rust mites (page 320), feed on the surface of leaves and needles, producing a bronzing of foliage. Injury to developing fruit and flowers is also produced by some eriophyid mites.
Gross distortions of the male flowers of green ash are produced by the ASH FLOWERGALL MITE (Aceria fraxiniflora),1 causing the flowers to enlarge and persist on the trees, usually becoming noticeable after leaf fall. Similar distortions of flowers are produced on walnuts by A. neobeevori. COTTONWOOD CATKINGALL MITE (Eriophyes neoessigi)1 induces the catkins of various cottonwoods to grossly enlarge, in some cases to the size of a small cluster of grapes.
Cottonwood catkin gall. WHITNEY CRANSHAW
Bud abortion and distortion of flowers can be produced by the CAMELLIA BUD MITE (Cosetacus camelliae),1 now widely distributed in the southeastern states and California. BLUEBERRY BUD MITE (Acalitus vaccinii)1 deforms buds and berries of blueberry and huckleberry throughout much of the eastern U.S., particularly in the southeastern states. REDBERRY MITE (A. essigi)1 damages cultivated and wild blackberries, producing irregular ripening in the form of hard red or green drupelets. Redberry mite is most common in the Pacific States, but known to occur in the Midwest. DRYBERRY MITE (Phyllocoptes gracilis)1 develops on leaves, buds and fruit of raspberry, blackberry and loganberry. Injuries to fruit can resemble sunscald. Juniper berries are often heavily infested by JUNIPER BERRY MITE (Trisetacus quadrisetus)2 in western North America, causing seed to abnormally form.
Irregular ripening of blackberry due to redberry mite. ART ANTONELLI, WASHINGTON STATE UNIVERSITY
Several of the leaf-feeding rust mites also colonize fruit, producing a bronzing and roughening of the fruit skin known as “russeting.” PEAR RUST MITE (Epitrimerus pyri)1 produces bronzing of both pear fruit and foliage. APPLE RUST MITE (Aculus schlechtendali)1 produces similar injury to apple and is occasionally also found on pear. CITRUS RUST MITE (Phyllocoptruta oleivora)1 occurs in all citrus-producing regions. On orange it produces a rust-colored symptom on the surface; symptoms on lemon are more silvery. PINK CITRUS RUST MITE (Aculops pelekassi)1 is the more damaging citrus-feeding rust mite in Florida, causing fruit russeting and leaf bronzing. Along the coastal areas of California, CITRUS BUD MITE (Eriophyes sheldoni)1 can be damaging, causing distortions of developing leaves and fruit.
1 Acari: Eriophyidae
2 Acari: Phytoptidae
B. Ash flowergalls. JIM KALISCH, UNIVERSITY OF NEBRASKA
C. Damage by blueberry bud mite. JERRY A. PAYNE, USDA AGRICULTURAL RESEARCH SERVICE, BUGWOOD.ORG
D. Pearleaf blister mite damage to leaves and fruit. HAROLD J. LARSEN, COLORADO STATE UNIVERSITY
E. Skin russeting by pear russet mite. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA STATEWIDE IPM PROGRAM
F. Skin russeting produced by citrus rust mite. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA STATEWIDE IPM PROGRAM
G. Damage to citrus bud by citrus bud mite. JACK KELLY CLARK, COURTESY OF UNIVERSITY OF CALIFORNIA STATEWIDE IPM PROGRAM
