Twenty-five Pests You Don't Want in Your Garden

Twenty-five PestsYou Don’t Want in

Your Garden

Prepared by the PA IPM Program

J. Kenneth Long, Jr. PA IPM Program Assistant

(717) 772-5227 [email protected]

Pest Pest Sheet

Aphid 1Asparagus Beetle 2Bean Leaf Beetle 3Cabbage Looper 4Cabbage Maggot 5Colorado Potato Beetle 6Corn Earworm (Tomato Fruitworm) 7Cutworm 8 Diamondback Moth 9European Corn Borer 10Flea Beetle 11Imported Cabbageworm 12Japanese Beetle 13Mexican Bean Beetle 14Northern Corn Rootworm 15Potato Leafhopper 16Slug 17 Spotted Cucumber Beetle (Southern Corn Rootworm) 18 Squash Bug 19Squash Vine Borer 20Stink Bug 21Striped Cucumber Beetle 22Tarnished Plant Bug 23Tomato Hornworm 24Wireworm 25

PA IPM Program Pest Sheet 1

AphidsMany species (Homoptera: Aphididae)

(Origin: Native)

Life History: Females lay eggs near the endof the growing season in protected places onhost plants. In spring, plump “stemmothers” emerge from these eggs, and givelive birth to daughters, and they give birthto more daughters, all without mating. Atthe end of the growing season, males areproduced, and females born at the sametime have eggs rather than live young inthem. Mating occurs, the eggs are fertilizedand overwintering eggs are again laid inprotected areas on the plants.

Insect Description:Adults: About 1/8” long; soft-bodied; light todark green; may be winged or wingless.Cornicles, paired tubular structures onabdomen, are helpful in identification.

Nymph: Daughters are born alive contain-ing partly formed daughters inside theirbodies. (See life history below).

Eggs: Laid in protected places only near theend of the growing season.

Soybean Aphids

Primary Host: Many vegetable crops.

Damage: Adults and immatures suck sap fromplants, reducing vigor and growth of plant.Produce “honeydew” (sticky liquid) on which ablack fungus can grow.

Management: Hide under leaves. Because ofsmall size, hidden behavior and rapid repro-duction, populations can become very largebefore they are noticed.

Biocontrols: Several natural enemies such aslady beetles and lacewings feed on them.Several parasitoids lay eggs within aphids,killing them as the nymphs develop.

Cultural Controls: Avoid high nitrogen levels inplants (enhances aphid reproduction) by usingless soluble forms of nitrogen.

Physical Controls: Proper pruning and washingaphids off with a strong stream of water canhelp.

Chemical Controls: Contact your local Penn State County Extension Agent for more informationhttp://www.extension.psu.edu/extmap.html

Asian Lady Beetle feeding on Aphids

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Soybean aphids: David W. Ragsdale, U of Minn, www.insectimages.org; Asian Lady Beetle feeding on aphids: Marlin E. Rice, Iowa State University, www.ent.iastate.edu.


Asparagus BeetleCrioceris asparagi (L.) (Coleoptera: Chrysomelidae)

(Origin: European)

Insect Description:Adults: !” long; with bluish head, reddishneck, and creamy yellow spots with redborders on the wings. (Adult spottedasparagus beetles are larger, reddish orangewith black antennae, eyes and undersidesand 6 black spots on each wing.)

Pupae: Located in the soil below theasparagus plants.

Larvae: 3/8” long; soft-bodied, gray withblack heads.

Eggs: Black (Spotted asparagus beetle’s areyellowish-green.)

Adult Asparagus Beetle

Primary Host: Asparagus

Damage: Adults feed on tips of shoots as soon asthey push through the ground, causing scarsand browning of tips. Adults and larvae feed onstem and leaf surfaces. Larvae excrete blackfluid that stains plants.

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Asparagus Beetle Adult: Clemson University – USDA Cooperative Extension Slide Series,www.insectimages.org; Asparagus Beetle Larva: Clemson University – USDA Cooperative Extension Slide Series, www.insectimages.org.

Asparagus Beetle Larva

Life History: Overwinter as adults in anysuitable shelter like loose tree bark orhollow stems of old asparagus plants. Aboutthe time of first asparagus cutting, theymake their way to the young shoots and layeggs on them. The larvae feed about 2 weeksbefore dropping to the soil to pupate. Thereare 2 generations each year. The activebeetles often drop to the ground ifdisturbed.

Management: Regular cutting helps reducedamage.

Biocontrols: A tiny (1/8”) metallic green wasp,Tetrastichus asparagi, parasitizes asparagusbeetle eggs.

Cultural Controls: Control volunteer plants tohelp reduce damage. Destroying crop residueeliminates overwintering sites for the adults.

Physical Controls: Hand picking is best in smallpatches. In summer, brushing the plants with abroom to knock off the larvae will help. Controlduring summer and fall may eliminate theproblem for the next year.

Chemical Controls: Contact your local Penn State County Extension Agent for more info. http://www.extension.psu.edu/extmap.html


Bean Leaf BeetleCerotoma trifurcata (Förster) (Coleoptera: Chrysomelidae)

(Origin: Native)

Insect Description:Adults: About !” long; varies in color fromlight yellow to tan to green or even red whenmature. Each wing cover may have 4 blackspots and there is a black triangle behindthe head.

Pupae: Whitish in color and about 1/6” long.Found in small earthen cell in the soil.Adults emerge in about a week.

Larvae: Slender and white, about 1/3” long,with a black head and anal plate and shortlegs near the head. (Resembles cornrootworm larva). It spends this entire stagefeeding underground until pupation.

Eggs: Lemon-shaped; reddish-orange incolor and less than 1/32” long. Laid about 1”deep in soil in clusters at the base of plants.Hatch within 2-3 weeks depending ontemperature.

Adult Bean Leaf Beetle

Primary Host: Beans, peas, soybeans.

Damage: Larvae feed on roots, nodules, andunderground portions of the stem. Adults feedon stems of seedlings and chew round holes inleaves and damage pods.

Management: 2 or 3 beetles per plant and 30%defoliation usually justifies treatment.

Biocontrols: Many different parasitoids andpredators attack bean leaf beetles. The mostcommon parasitoid is the tachinid fly, Calatoriadiabroticae, which attacks the adult beetle.

Cultural Controls: An early planting of soy-beans may serve as a trap crop if the number ofoverwintering adults is high.

Chemical Controls: Contact your local Penn State County Extension Agent for more information.http://www.extension.psu.edu/extmap.html

Life History: Overwinters in wooded areas,leaf litter and weeds. Migrate to bean fieldsto feed and lay eggs. Eggs hatch in 6-15days. Larvae feed on soybean root hairs andnodules until pupation. 2nd generation adultsemerge and feed on soybean foliage.

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Bean Leaf Beetle Adult: Marlin E. Rice, Iowa State University, www.ent.iastate.edu.


Cabbage LooperTrichoplusia ni (Hübner) (Lepidoptera: Noctuidae)

(Origin: ?)

Cabbage Looper Adult

Management: Usually more serious in the fall.Should be controlled when small because largeloopers are difficult to control.

Biocontrols: The tachinid fly, Voria ruralis, isthe dominant cause of cabbage looper death.

Cultural Controls: Plant resistant varieties suchas Mammoth Red Rock or Chieftan Savoy.

Physical Controls: Hand picking works forsmall patches. Cover plants with a floating rowcover to keep adults from laying eggs on plants.

Chemical Controls: Contact your local Penn State County Extension Agent for more information. http://www.extension.psu.edu/extmap.html

Primary Host: Cabbage, cauliflower, broccoli,Brussels sprouts, radish, mustard, kale, lettuce,celery, spinach, beets, peas, potato, tomato.

Damage: Caterpillars eat large irregular holesin leaves and into heads, causing stuntedgrowth, failure of heads to form, or makeproduce unmarketable.

Insect Description:Adults: Forewings mottled gray-brown incolor with silvery white spots. Hindwingsare brown at base and near the edge. Wing-span is about 13/8” in extent.

Pupae: White, thin, fragile cocoon onunderside of foliage, in plant debris, or insoil clods.

Larvae: Light green. When crawling, makea characteristic loop in the middle of theirbody.

Eggs: Yellowish white or greenish, usuallylaid singly on underside of mature leaves.

Life History: Cabbage loopers overwinter aspupae attached to host plants and othernearby objects. The adults emerge in thespring and lay several hundred eggs singlyon the upper surfaces of host plant leaves.Larval development may be completed intwo weeks if weather is favorable, and thecabbage looper can have three or moregenerations per year in the northern UnitedStates.

Cabbage Looper Larva

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Cabbage Looper Adult: John L. Capinera, University of Florida, http://creatures.ifas.ufl.edu/;Cabbage Looper Larva: R.J. Reynolds Tobacco Company Slide Set, R.J. Reynolds Tobacco Company, www.insectimages.org..


Cabbage MaggotDelia radicum (L.) (Diptera: Anthomyiidae)

(Origin: Native)

Life History: Overwinter as pupae in thesoil. Flies emerge from soil in late April orearly May, feed on pollen and nectar, andlay white eggs at bases of newly set plants.Larvae from this generation tunnel in theroots of small plants, causing plants tobecome stunted. When mature, maggotspupate in roots or surrounding soil. Disk orrototill 2 weeks before planting to destroythe pupae.

Insect Description:Adults: !” long gray body with 3 blacklongitudinal stripes on thorax and 1 blackstripe along top of abdomen. Resemblesmall house flies.

Pupae: About !” long and brown.

Larvae: Small, legless, white maggots,reaching maximum length of about !”.

Eggs: Oval shaped, bone white and verysmall. Usually on plant or soil near the stem.

Adult Cabbage Maggot

Primary Host: Crucifers.

Damage: Larvae tunnel into roots of smallplants causing plants to appear sickly, off coloror stunted, and may cause plant to die. Cabbagemaggot injury is favored by cool, wetconditions.

Management: Plowing under crop residuesafter harvest will destroy many pupae.

Biocontrols: Ground beetles and nematodesmay help control maggots.

Cultural Controls: High levels of organicmatter may increase the attractiveness of thefield to cabbage maggot flies.

Physical Controls: Cover plants with floatingrow cover to keep adult flies from laying eggson plants.

Chemical Controls: Contact your local Penn StateCounty Extension Agent for more information.http://www.extension.psu.edu/extmap.html

Cabbage Maggot Larva

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Cabbage Maggot Adult and Larva: Agriculture and Forestry Information Centre: http://www.gov.pe.ca/af/agweb/library/gallery/search/search_3.php3?category=Cabbage%20maggot.


Colorado Potato BeetleLeptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae)

(Origin: Central America, Mexico, Caribbean)

Life History: Overwintering adults emergein late May, begin to feed and mate. Eggslaid in June hatching in about 1 week. 2weeks later, mature larvae drop to groundand pupate. A week later, adults emerge andbegin the 2nd generation. New adults in lateJuly or August may feed a few days thenbegin winter hibernation in the ground.

Insect Description:Adults: About 3/8” in length; oval shaped.Cream colored with 10 black stripes on theback.

Pupae: Located in soil.

Larvae: Early stages are crimson with blacklegs and 2 rows of black spots on sides ofbody. Later stages are orange and appearbloated and humpbacked.

Eggs: Deposited in orange clusters of 20-45oval-shaped eggs under leaves.

Colorado Potato Beetle Adult

Primary Host: Potato, tomato, eggplant, pepper.

Damage: Adults and larvae feed on leaves andterminals, causing reduced growth or death ofplant.

Management: Needed primarily duringflowering for potatoes.

Biocontrols: A lady beetle (Coleomagillamaculata), and a predaceous stinkbug feed onthe eggs.

Cultural Controls: Crop rotation prevents over-wintering beetles from emerging directly in thefields. Till in fall to reduce damage.

Physical Controls: Mulches and trenches, andhand picking and row covers are effective.

Chemical Controls: Contact your local PennState County Extension Agent for moreinformation.http://www.extension.psu.edu/extmap.html

Colorado Potato Beetle Larva

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Colorado Potato Beetle adult: USDA Image Gallery, www.ars.usda.gov/is/graphics/photos/;Colorado Potato Beetle larva: Kansas State University, Department of Entomology: www.oznet.ksu.edu/.


Corn Earworm (Tomato Fruitworm)Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae)

(Origin: Native)

Corn Earworm Adult

Life History: Females prefer to lay eggs oncorn or tomato plants, usually near flowersor terminal leaflets. After hatching, larvaequickly begin to bore deeply into the fruit,contaminating it with feces. Larvae prefergreen fruit and seldom enter ripe fruit.

Corn Earworm Pupa with Parasite

Insect Description:Adults: Buff colored; with irregular spotsand markings on wings. About 1"” wing-span.

Pupae: Initially a shiny reddish brown, itbecomes dark brown when adult emergenceapproaches.

Larvae: Light green to tan or other colors,with light and dark stripes runninglengthwise on body. Head capsule is lightbrown.

Eggs: Preferred site for laying is fresh cornsilks.

Management: Monitor with pheromone traps.

Biocontrols: Several predators and parasites,including ladybird beetles, lacewings, predatorybugs, and parasitic flies and wasps attackearworm eggs and larvae

Cultural Controls: Cut off the tips of damagedsweet corn ears or plant extra tomatoes orbeans.

Physical Controls: Mineral oil can be applied tothe corn silk to prevent egg laying.

Chemical Controls: Contact your local PennState County Extension Agent for moreinformation.http://www.extension.psu.edu/extmap.html

Primary Host: Corn, tomato, beans, peppers, eggplant, tobacco.

Damage: Larvae feed on marketable portion ofeach vegetable crop it attacks, often makingthem unmarketable. Usually enter corn earsthrough the tip.

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Corn Earworm adult: Steve L. Brown, The University of Georgia, www.insectimages.org; Corn Earworm Pupa with parasite: USDA Image Gallery, www.ars.usda.gov/is/graphics/photos/.


CutwormsSeveral species (Lepidoptera: Noctuidae)

(Origin: Native or exotic)

Life History: Many Overwinter as pupae inthe soil or as adult moths. Eggs aredeposited early in spring. Several cutwormshave more than one generation per year.Larvae hide in the soil during the day andmove to the soil surface at night where theycut off plants just above the soil surface,causing the plants to die.

Insect Description:Adults: Large moths (1"” wingspan). Mostcutworm moths are brownish with somewing markings.

Larvae: Smooth skinned, dull brownishcaterpillars up to 1"” in length, that curlinto a C-shape when disturbed. Normallyfound on or just below the soil surface or onlower parts of plants. Start feeding in earlyspring. Eat at night.

Pupae: Found in the soil for most species.

Eggs: Laid mostly on broad-leaved weedstems and leaves.

Black Cutworm Adult


Damage: Feed at night and can cut small plantsoff at the soil surface. On older plants,treatment should not be necessary. Somecutworms climb and feed on all plant parts.

Management: Blacklight or pheromone trapscan be used for monitoring. If seedlings are cutoff at soil level, cutworms should be suspected.

Biocontrols: Birds, insect predators such asground beetles, and hymenopteran parasitoidsfeed on cutworms.

Cultural Controls: Fields with many winterannual weeds should be worked at least 10-14days before transplanting seedlings. Transplantseedlings when large enough to withstand alittle damage.

Physical Controls: Paper collars or otherbarriers placed around seedlings will protectthem from cutworm attack.


Cutworm Larva showing damage

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Black Cutworm adult: Marlin E. Rice, Iowa State University, www.ent.iastate.edu; Cutworm larvae showing damage: University of Georgia Archives, The University of Georgia, www.insectimages.org.


Diamondback MothPlutella xylostella (L.) (Lepidoptera: Pyralidae)

(Origin: Europe)

Life History: The life cycle can be comp-leted in two weeks to a month dependingon temperatures. Upon hatching fromthe eggs, larvae tunnel into the leavesmining them for about a week. Theythen exit through the underside and feedexternally. When disturbed, the larvaedrop on a silken thread, and later climbback onto the leaf.

Insect Description:Adults: About 3/8” long; gray or brown-ish color with 3 pale triangular markingsalong the inner margin of wings. At rest,the triangles form 3 diamond shapesalong the middle of the wings.

Pupae: White silk mesh cocoon formedon surface of leaf or in litter under theplant; about 3/8” long.

Larvae: About 3/8” long; light brown todark green in color. Usually found onthe undersides of leaves.

Eggs: Tiny, yellow, laid under leavesnear veins.

Adult Diamondback Moth

Management: Caterpillars are detected byvisual observation of the plant. Adults can bedetected with pheromone traps.

Biocontrols: Several hymenopterous parasitoidswill attack the caterpillars.

Cultural Controls: Plant resistant varieties ofcrops.

Physical Controls: Moths overwinter in thefield, so destroying or plowing under cropdebris is recommended.


Primary Host: Cabbage, cauliflower, broccoli, Brussels sprouts, radish, mustard, kale.

Damage: Larvae eat many small holes onunderside of leaves, giving plant a shot-holeappearance.

Diamondback Moth Larva

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Diamondback Moth adult: Archives of the IPM Program at NY State Ag Experiment Station,www.nysaes.cornell.edu; Corn Diamondback Moth larva: USDA Image Gallery, www.ars.usda.gov/is/graphics/photos/.


European Corn BorerOstrinia nubilalis (Hübner) (Lepidoptera: Pyralidae)

(Origin: Europe)

European Corn Borer Larva

Life History: 1st generation larvae over-winter in stalks of host plant, transform intopupae in late April to early June. Adultsemerge and lay eggs mid-May to mid-June.Larvae chew holes in leaves, then into stalk,where they pupate. 2nd generation mothsemerge in late July to late August. Larvaecomplete growth before cold weather andwinter in plants.

Insect Description:Adults: Yellowish buff to light tan with darkzigzag marks across wings. Wing spread #-1”.

Pupae: Remains inside host plant; smooth,light to dark brown in color; 1/3-

5/8” inlength.

Larvae: Dirty white, smooth skin with manydark spots over sides and top of body; hair-less; with dark head.

Eggs: Glued to underside of leaves inclusters of 12 or more resembling over-lapping fish scales.

European Corn Borer Adults

Management: Monitor with black light orpheromone traps.

Biocontrols: Trichogramma ostriniae parasitizeegg masses of the European Corn Borer.

Cultural Controls: Choose hybrid withtolerance to corn borers. Shred or bury oldstalks to kill over-wintering larvae.

Physical Controls: Keep weedy field edges andfence rows clipped to avoid a harbor for themoths.


Primary Host: Corn, peppers and beans.

Damage: Larvae feed on foliage and ears ofcorn, bore inside pepper fruit, and feed on orbore into bean pods.

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: European Corn Borer adult: Marlin E. Rice, Iowa State University, www.ent.iastate.edu/imagegal/;European Corn Borer Larva: Penn State University, www.ento.psu.edu/.


Flea BeetlesMany species (Coleoptera: Chrysomelidae)

(Origin: Native and Exotic)

Insect Description:Adults: Small, shiny beetles with back legsenlarged for jumping like fleas whendisturbed.

Corn Flea Beetle: 1/16”, strips the green toplayer from leaves, leaving irregular brownor grey lines. Can transmit bacterium ofStewart’s wilt.

Potato Flea Beetle: small, 1/16” long, black.

Striped Flea Beetle: 1/12”, pale stripe on eachwing.

Larvae: Usually feed on roots of host plant.

Life History: For most species, adults over-winter underground or beneath plantdebris. During April and May, they becomeactive, mate and lay eggs. Eggs typicallyhatch in 10 days. Larval and pupal develop-ment take place during the summer. “New”adults emerge and feed during late summerand fall before seeking overwintering sites.

Adult Flea Beetle

Primary Host: Many vegetable crops. Eggplant is especially vulnerable to attack.

Damage: Chew small holes in leaves, giving theleaf a “shot hole” appearance.

Management: Focus on protecting the youngestplants from attack.

Biocontrols: None known to be effective.

Cultural Controls: Weed control in and aroundplanting sites deprive larvae of food sources;remove crop debris to eliminate overwinteringsites; delayed planting may avoid peak pop-ulations; rotation of crops.

Physical Controls: Row covers can protectseedlings.


Flea Beetle Damage

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Flea Beetle adult: Hariet Hinz & Ester Gerber, CABI Biosciences, www.insectimages.org; Flea Beetle damage: Kansas State University, Department of Entomology: www.oznet.ksu.edu/.


Imported CabbagewormPieris rapae (L.) (Lepidoptera: Pieridae)

(Origin: Europe)

Life History: Overwinter as pupae attachedto host plant debris. Adults emerge early inspring. Soon after mating, eggs aredeposited singly on host plants. Larvae arecommonly found on under-sides of leaves,and bore into the center of the head as theygrow. When mature, a chrysalis is formed.There may be several generations in a year.

Insect Description:Adults: Common white butterfly with blackspots and wing tips. The female has 2 spotson each forewing, while the male has 1.

Pupae: Sharply angled chrysalis is gray,green, or brown, attached to lower leafsurface by silken loop.

Larvae: Velvet-like green larva has a faintyellow stripe down its back, and a row offaint yellow spots on each side.

Eggs: Tiny, pale yellow, bullet-shaped.

Imported Cabbageworm Adult

Management: Masses of wet, greenish-brownexcrement deep among leaves is characteristicof this pest.

Biocontrols: Several hymenopterous parasitoidsattack the caterpillars as well as virus andbacterial diseases.

Cultural Controls: Resistant cabbage varietiesshould be planted. Row covers prevent egglaying.

Physical Controls: Handpick larvae and eggs.


Primary Host: Cabbage, cauliflower, broccoli,Brussels sprouts, radish, mustard, kale, lettuce.

Damage: Caterpillars eat large irregular holesin leaves and into heads, causing stuntedgrowth, failure of heads to form, or makeproduce unmarketable.

Imported Cabbageworm Larva

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Imported Cabbageworm adult: James Castner, University of Florida/IFAS, March 2000: http://edis.at.ufl.edu/IN283; Imported Cabbageworm larva: USDA Image Gallery, Clemson University – USDA Cooperative Extension Slide Series, www.insectimages.org.


Japanese BeetlePopilia japonica Newman (Coleoptera: Scarabaeidae)

(Origin: Asia)

Insect Description:Adults: About 3/8” long; metallic green andbronze in color with a row of white tufts oneach side of body.

Pupae: First cream-colored, becoming lightreddish-brown with age. About "” long.

Larvae: Common C-shaped white grubsfound in lawns, turf or cultivated fields.

Eggs: Tiny white eggs are deposited in thesoil where they hatch.

Life History: Grubs overwinter about 8”below the soil surface, moving up when thesurface temperature reaches 60°. Pupationbegins in June, with adults emergingthrough July, feeding and mating. Thefemale burrows into the soil to lay eggsabout 2-4” deep, where they hatch intogrubs which begin feeding on roots andorganic material. As winter approaches, thegrubs burrow deeper to overwinter.

Japanese Beetles Adult

Management: Adults are not effectively con-trolled with scented traps.

Biocontrols: Bacterial Milky Disease is effectivegiven enough time, and a parasitic nematode iseffective.

Cultural Controls: Dry soil inhibits developmentof eggs and 1st stage grubs. Don’t irrigate duringthat time.

Physical Controls: Hand picking. Pheromonetraps may attract more beetles than they control,causing increased plant damage.


Primary Host: Many vegetables, fruits, fieldcrops, ornamentals, turfgrass.

Damage: Larvae (grubs) feed on roots of turf-grass and other plants. Adults feed on leaves,flowers, and fruits of many plants.

Japanese Beetle Larva (Grub)

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Japanese Beetle adult and grub: Marlin E. Rice, Iowa State University, www.ent.iastate.edu.


Mexican Bean BeetleEpilachna varivestris Mulsant (Coleoptera: Coccinellidae)

(Origin: Central America, Mexico, Caribbean)

Insect Description:Adults: Round shaped and copper coloredwith 16 spots on its back. About 5/16” longand !” wide.

Pupae: About !” long, yellowish, withtraces of spiny larval skin attached.

Larvae: Yellow, oval, covered withbranched spines. 7/16” long when full grown.

Eggs: Oval, yellow, laid in clusters onunderside of bean leaf.

Life History: Eggs are laid from late springthrough early fall and hatch in 5-14 days.Young larvae feed on underside of leavesand older larvae eat through the leavesleaving only the veins. Pupae are attached toundersides of leaves of beans or nearbyweeds and develop in about 10 days.Adults live 4-6 weeks during the activeseason, and late season adults hibernate inwoodland areas or where crops have notbeen plowed under.

Mexican Bean Beetle Adult

Primary Host: Beans, soybeans.

Damage: Larvae and adults feed on under-surface of leaves giving them a lacy appearance.May also attack pods when abundant.

Management: One beetle per plant or 30%defoliation justify use of pesticide.

Biocontrols: Naturally occurring predators mayhelp reduce numbers.

Cultural Controls: Delayed planting mayreduce beetle populations.

Physical Controls: Hand picking works forsmall plots. Heavy rains help knock off adultsand larvae from plants.

Chemical Controls: Contact your local Penn StateCounty Extension Agent for more information.http://www.extension.psu.edu/extmap.html Spined Soldier Bug feeding on

Mexican Bean Beetle Larva

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Mexican Bean Beetle adult: Clemson University – USDA Cooperative Extension Slide Series,www.insectimages.org; Spined Soldier Bug feeding on Mexican Bean Beetle larva: USDA Image Gallery, www.ars.usda.gov/is/graphics/photos/.


Northern Corn RootwormDiabrotica barberi Smith & Lawrence

(Coleoptera: Chrysomelidae)(Origin: Native)

Life History: Overwinter as eggs in the soil.They hatch about mid-June. The tinyrootworms immediately begin searching forcorn roots to feed on. Pupae develop aboutmid-July, with adults emerging in late July.Only 1 generation is produced per year.

Corn Rootworm Larva

Insect Description:Adults: About !” long; solid yellowish-green in color. Good flyers.

Western Corn Rootworm: males are mostlyblack on the wing covers while females arestriped with yellow under the abdomen.(Striped Cucumber Beetles have a blackabdomen).

Pupae: In the soil; white, with no protectivecovering.

Larvae: White and slender; only foundunderground feeding on corn roots.

Eggs: Deposited in soil near the base of cornplants.

Management: Monitor about mid-August foradult beetles on tips of corn ears. 200 or moreper 100 plants may cause loss in the same fieldnext year.

Biocontrols: No effective ones are commerciallyavailable.

Cultural Controls: Plant corn more than 5 daysafter rootworm egg hatch to prevent larvalfeeding.

Physical Controls: Crop rotation can effectivelyprevent infestation. Rootworms are seldom aproblem in sandy soils.


Primary Host: Corn.

Damage: Adults feed on pollen, corn silks,leaves and exposed corn kernels. Larvae tunnelinto roots, often pruning them back to thecrown, causing stunting and lower yields. Plantswith badly damaged roots often topple overduring storms.

Northern Corn Rootworm Adult

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Northern Corn Rootworm adult: Marlin E. Rice, Iowa State University, www.ent.iastate.edu; Corn Rootworm larvae, USDA Image, www.ars.usda.gov/is/graphics/photos/.


Potato LeafhopperEmpoasca fabae (Harris) (Homoptera: Cicadellidae)

(Origin: Native)

Potato Leafhopper Nymph and Adult

Life History: Does not overwinter inPennsylvania. Adults are blown up from thesouth in late May and early June. Once theyarrive, females deposit 1-6 eggs daily inplant stems. The total period from egg toreproductive maturity is about 28 daysunder favorable conditions. There can beseveral overlapping generations during thegrowing season. Both nymphs and adultsinject saliva into plants as they feed. Theycan remain active until killed by fall frosts.

Insect Description:Adults: Tiny (about 1/8” long); wedge-shaped, yellow-green insects which fly, jumpor run sideways when disturbed. Wings areheld roof-like over the body.

Nymph: Smaller versions of the adults, butwingless, and walk sideways.

Eggs: Laid singly within the petioles andveins on undersurfaces of host plants. Hatchin about 10 days.


Damage: Characteristic wedge-shaped yellowarea at leaf tip (“hopperburn”). Damage mayspread over many entire leaves. Stunted plantsand reduced yields may result.

Management: Monitor by net sweeping begin-ning in early June.

Biocontrols: Several predators, parasites andfungal pathogens attack Potato Leafhoppers.

Cultural Controls: Vigorously growing plantsmore easily withstand feeding damage. Cropsnear alfalfa fields tend to suffer more damageespecially after the alfalfa is cut.

Physical Controls: Floating row covers cankeep Potato Leafhoppers off plants.


Potato Leafhopper size

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Potato Leafhopper: Marlin E. Rice, Iowa State University, www.ent.iastate.edu/imagegal/, Potato Leafhopper size: Penn State University, http://paipm.cas.psu.edu/CropAlert/IPM_potato.html.


SlugsMany species (Mollusca: Gastropoda)

(Origin: many European)

Slug Eggs

Life History: Overwinter in the egg or adultstage, depending on the species. Juvenileslugs hatch from eggs as soon as soil warmsin the spring. Each slug possesses both maleand female organs, and produces clumps of10-20 eggs laid in crevices in the soil, underdebris, or other protected locations. Preferdark, moist areas like under boards, rottingmulches, trash, etc. and feed at night. Theyfeed by rasping the leaf tissue, leaving aragged shredded appearance to the leaf.Slugs move on their bellies and leave asilver-colored slimy trail wherever theytravel.

Description: Slugs are not insects, but arelegless mollusks, like snails without shells.

Adults: Soft-bodied; grayish or mottledslimy mollusks that may reach up to 4” long.Have 2 pairs of retractable tentacles witheye spots on the tips of the longer.

Immatures: Resemble small adult slugs.

Eggs: Colorless, gelatinous appearance,round to oval in shape.

Field Slug

Management: More of a problem in cool, wetweather. Several days of warm, sunny weathermay reduce the problem.

Biocontrols: Toads, some beetles and theirlarvae, parasitic flies and birds are naturalenemies of slugs, but are not very dependable.

Cultural Controls: Eliminate hiding places.Remove rotting boards and debris. Keepgardens weeded and grass cut short.

Physical Controls: Small pans or canning lidssunk into the ground and filled with a mixtureof yeast and water may attract and drown slugs.Trap them by laying boards between gardenrows and collect them in the morning.


Primary Host: Many vegetables.

Damage: Slugs make ragged holes in leavesbeginning with lower leaves. Leaves mayappear shredded. Silvery slime trails are telltalesigns of slugs or snails.

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Field Slug: Marlin E. Rice, Iowa State University, www.ent.iastate.edu/imagegal/, Slug eggs: DavidJ. Shetlar, Ohio State University: http://ohioline.osu.edu/hyg-fact/2000/2010.html.


Spotted Cucumber Beetle(Southern Corn Rootworm)

Diabrotica undecimpunctata howardi Barber(Coleoptera: Chrysomelidae)

(Origin: Native)

Insect Description:Adults: Greenish-yellow with 12 black spotson wing covers. About 1/5” long.

Pupae: White pupae are in the soil near thebase of the plants on which the larvae fed.

Larvae: White larvae that remain in theground feeding on roots of the host plants.

Eggs: Orange-yellow, laid around the baseof host plants, often below the soil surface. Primary Host: Cucurbits (cucumbers, melons,

squash, gourds, pumpkins, watermelons),Corn.

Damage: Adults feed on leaves and blossoms.Feeding on young seedlings can result instunting or death of the plant. Can transmit abacterium that causes bacterial wilt. Larvaefeed on roots.

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Spotted Cucumber Beetle adult: Clemson University – USDA Cooperative Extension Slide Series,www.insectimages.org; Spotted Cucumber Beetle larva, USDA Image Gallery, www.ars.usda.gov/is/graphics/photos/.

Life History: Overwinter as adults on edgesof fields or in woods under litter or otherplant debris and appear as plants are set.Feed extensively on leaves and stems inearly season. Eggs hatch in 5-8 days intowhite worm-like larvae that feed on roots.In 14-20 days, they pupate underground.Later, the adults that will overwinteremerge from the ground and feed oncucumbers and melons.

Spotted Cucumber Beetle Larvae

Management:Biocontrols: No effective ones are commerciallyavailable.

Cultural Controls: Plant corn more than 5 daysafter rootworm egg hatch to prevent larvalfeeding.

Physical Controls: Crop rotation can effectivelyprevent infestation. Floating row covers canprotect from the adults.


Spotted Cucumber Beetle Adult


Squash BugAnasa tristis (DeGeer) (Hemiptera: Coreidae)

(Origin: Native?)

Insect Description:Adults: Flat-backed bugs about 5/8” long.Dark gray-white body with black legs andantennae. When crushed give off anunpleasant odor.

Nymphs: 5 nymphal stages take about 33days to develop. Young nymphs have a redhead, antennae, thorax and legs, and a greenabdomen. With age, they darken anddevelop black legs and antennae.

Eggs: Oval shaped and yellowish-brown.Deposited in clusters of 4-40 eggs in rows.

Primary Host: Serious pest of squash, melons,pumpkins, and cucumbers.

Damage: Nymphs and adults suck plant juicescausing leaves to wilt and die. Both will feed ondeveloping fruit.

Management: Monitor to prevent populationbuild-up. Wilted plants should be examined forsquash bugs.

Biological Controls: A parasitoid fly(Trichopoda pennipes) lays eggs in the female,feeding on her inner parts.

Cultural Controls: Mow field edges and removedebris after harvest from around the field tokill overwintering squash bugs.

Physical Controls: Placing old boards in thefield before cool nights often attract the bugs.Early the next morning they can be capturedand eliminated.

Chemical Controls: Contact your local Penn StateCounty Extension Agent for more information.http://www.extension.psu.edu/extmap.html Squash Bug Nymph

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Squash Bug adult: Penn State University, www.ento.psu.edu/extension/factsheets/squash_bug.htm;Squash Bug nymph: John Capinera, University of Florida, creatures.ifas.ufl.edu/veg/leaf/squash_bug.htm.

Life History: Overwintering adults emergein late June, feed and mate and begin layingeggs in about 10 days. Eggs hatch in about 1–2 weeks and develop into adults in about 4-6 weeks. There is no pupa stage, with eachnymphal stage looking more like the adult.There is only one generation a year. Adultsoverwinter in protected areas.

Squash Bug Adult and Eggs


Squash Vine BorerMelittia cucurbitae (Harris) (Lepidoptera: Sesiidae)

(Origin: Native)

Life History: Overwinter as pupae insidetough silk-lined cocoons in the soil. Adultmoths emerge in late June. Moths fly duringthe warm part of the day and lay eggs on thestems near the soil surface. Eggs hatch inabout 10 days and the tiny borers enter thestems, hollowing out the stems. Toward theend of the season when vines become woodyand less succulent, the borers may attackthe fruit. Borers leave the plant in Augustand September, when mature and enter thesoil to form their overwintering cocoons.

Insect Description:Adults: A clear-winged moth that looks likea wasp with metallic olive-brown wings anda red-orange body. Wing spread is 1!”.

Pupae: Cocoons are formed in the soil foroverwintering.

Larvae: 1” long white grub-like caterpillarthat enters the vine and feeds, pushing outmasses of greenish-brown sawdust-likefrass.

Eggs: Reddish-brown eggs are laid on thevines when the vines begin to run.

Adult Squash Vine Borer

Primary Host: Squash, zucchini, pumpkins andgourds. Butternut squash is less susceptible todamage.

Damage: Larvae bore into the vine, causing asudden wilting of a vine or an entire plant.

Management: One of the 1st signs of infestationis yellow pellets of frass on the soil surface nearthe plant base.

Biocontrols: No commercially effective ones areavailable.

Cultural Controls: Rotate crops and till todestroy overwintering insects. Vines shouldalways be destroyed following harvest toprevent late caterpillars from completing theirdevelopment.

Physical Controls: Protect plants with rowcovers when vines begin to run. Cut open borerentry holes in the stem with a knife; thenremove the larva and pack moist earth aroundthe stem.


Squash Vine Borer Larva

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Squash Vine Borer adult and larva: Ric Bessin, University of Kentucky, www.uky.edu/Agriculture/.


Stink BugsSeveral species (Hemiptera: Pentatomidae)

(Origin: Native or Exotic)

Insect Description:Adults: Flattened, shield-shaped bug withpiercing mouthparts. A triangular-shapedplate partially covers its wings. Most speciesfeed on plants, but a few species arepredatory.

Nymph: Resemble wingless adults but arefrequently marked with different colors andlack the triangular plate.

Eggs: Clusters of barrel-shaped eggs.

Primary Hosts: Tomatoes, Soybeans

Damage: Stink bugs damage soybeans bypiercing pods and sucking fluid from thedeveloping beans causing the pods to formhardened, knotty spots or to drop from plants,or seeds to be smaller, shriveled, and/ordiscolored. Tomatoes are damaged by develop-ing hard, white spots just under the skin wherestink bugs have fed.

Management: Soybeans can be scouted bysweep net sampling.

Biocontrols: A Tachinid fly attacks stink bugs.

Cultural Controls: Avoid planting nearbrambles. Stink bug populations build up inberries and migrate to nearby gardens.

Physical Controls: Remove crop debris toeliminate overwintering sites.


Green Stink Bug Nymph

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Adult and nymph stink bugs: Marlin E Rice, Iowa State University, www.ent.iastate.edu/imagegal/.

Life History: Overwintering adults becomeactive in late spring, laying eggs which hatchinto nymphs. As nymphs grow, theyincrease in size and become more like theadult until wings have developed in the laststage. Both adults and nymphs suck juicesfrom the host plants, causing damage.

Adult Green Stink Bug


Striped Cucumber BeetleAcalymma vittata (F.) (Coleoptera: Chrysomelidae)

(Origin: Native)

Life History: Overwinter as adults on edgesof fields or in woods under litter or otherplant debris and appear as plants are set.Feed extensively on leaves and stems inearly season. Eggs hatch in 5-8 days intowhite worm-like larvae that feed on roots.In 14-20 days, they pupate underground.Adult feeding may transmit the bacteriumof bacterial wilt. Cantaloupes are verysusceptible to this disease. Once the plant isinfected, there is no control and the plantwill die.

Insect Description:Adults: About 1/3” long; black head;yellowish body; 3 stripes on back; blackabdomen. (Western Corn Rootworm hasyellow abdomen).

Pupae: White pupae are underground.

Larvae: White, worm-like, with a dark headand tip of abdomen, and feed on roots;about 1/3” long.

Eggs: Yellow, oval eggs laid in soil aroundhost plants.

Striped Cucumber Beetle Adult

Primary Host: Cucurbits (cucumbers, melons,squash, gourds, pumpkins, watermelons).

Damage: Larvae feed on roots and under-ground stems. Adults may destroy newlyemerged plants. On older plants, they feed onleaves, shoots, stems, flowers and fruits. Adultstransmit a bacterium that causes bacterial wilt.

Management:Biocontrols: No effective ones are commerciallyavailable.

Cultural Controls: Protecting plants with rowcovers before bloom will prevent beetle feedingand disease transmission.

Physical Controls: Yellow sticky traps about 2’above ground level may be useful when usedwith a bait like Eugenol.


Striped Cucumber Beetle Larva

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Striped Cucumber Beetle adult: USDA Image Gallery, http://www.ars.usda.gov/is/graphics/photos/,Striped Cucumber Beetle larva: UFL image: http://gcrec.ifas.ufl.edu/.


Tarnished Plant BugLygus lineolaris (Palisot de Beauvois) (Hemiptera: Miridae)

(Origin: Native)

Life History: Overwintering adults can befound in dead weeds, leaf litter, under treebark and other protected places. Theybecome active in spring and feed on newlydeveloping buds and shoots. Eggs areusually deposited singly and hatch in 7-10days. The nymphs develop into adults inabout 3-4 weeks. There are 4 or 5overlapping broods each year. These are oneof the most damaging of the true bugs andare known to transmit plant diseases.

Insect Description:Adults: Less than !” long; yellowish-brownhead, reddish-brown wings with some blackmarkings.

Nymph: Newly hatched are yellowish-green.As they grow, they develop yellow, green orblack spots. Resemble adults without wings.

Eggs: Tiny, laid on plant surfaces, often inleaf petioles. The top of the egg where itmeets the plant surface is flattened and hasan opening through which the nymphemerges.

Tarnished Plant Bug Adult

Management: Damage symptoms include leafragging, brown, discolored tissue, prematurebud drop, cat-facing and other symptoms.

Biocontrols: Several parasites are known, butthe egg parasite and nymphal parasites are themost effective.

Cultural Controls: Removal of weed hosts canhelp reduce damage.

Physical Controls: Destroy favorable over-wintering sites to reduce damage.


Primary Host: Beets, chard, celery, beans,potatoes, cabbage, cauliflower, turnips, salsify,cucumbers.

Damage: Suck plant juices and may inject toxicsaliva into plant. Leaves may become deformed,stems and petioles may be scarred anddiscolored, or the buds and developing fruitmay be dwarfed and pitted.

Tarnished Plant Bug Nymph

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Tarnished Plant Bugs: USDA Image Gallery, http://www.ars.usda.gov/is/graphics/photos/.


Tomato HornwormManduca quinquemaculata (Haworth)

(Lepidoptera: Sphingidae) (Origin: Native)

Insect Description:Adults: Brown or gray mottled with white.Hindwings have distinct dark zigzag stripesrunning diagonally. Wing spread is morethan 4”.

Pupae: Brown, hard-shelled, spindle-shapedand about 2” long. Found in the soil.

Larvae: Up to 3-4” in length, usually blue-green, have a “ tail” or horn on 2nd to lastsegment and have 7-8 white stripes runningdiagonally along side of body.

Eggs: Spherical greenish-yellow, laid on leafundersides.Primary Host: Tomatoes, potatoes, peppers,

eggplants.

Damage: Tomato hornworm and close relative,the tobacco hornworm eat large amounts ofgreen foliage.

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Tomato Hornworm adult: R.J. Reynolds Tobacco Company Slide Set, R.J. Reynolds Tobacco Company, www.insectimages.org; Tomato Hornworm larva: Robert L. Anderson, USDA Forest Service, www.insectimages.org.

Tomato Hornworm Larva

Life History: Overwinters as pupae in theground. In June or July, adults emerge,mate and lay eggs on the underside ofleaves. Within a week, larvae hatch andbegin feeding. Toward the end of August,the larvae drop to the ground, burrow inand pupate. There is one generation peryear.

Management: Easily detected by presence ofdroppings resembling those produced byrabbits.

Biocontrols: Parasites that pupate onhornworm’s body kills many of them. Do notdestroy hornworms with small white cocoons onthem. These are cocoons of parasites of thehornworms.

Cultural Controls: Fall plowing destroys manypupae.

Physical Controls: Hand pick larvae fromplants.


Tomato Hornworm Adult


WirewormsMany genera and species

(Origin: Native and Exotic)

Life History: Overwinter as larval or adultstages in the ground. In early spring theadults become active. Adults can live 10-12months spending most of the time in the soil.Wireworms can remain in the larval stage 3-7 years, depending on species. These aremainly pests in fields that have been in sodfor many years. Serious infestations areusually localized to a single field or portionsof a field.

Insect Description:Adults: Called click beetles, usually brownin color with streamlined bodies, taperingtoward the rear. The joint between thethorax and abdomen is flexible enablingthem to “click,” flipping up into the air toflip over when placed on their backs.

Pupae: Found in cells in the ground in latesummer or fall.

Larvae: Slender, smooth, hard-bodied, wire-like; chestnut-brown; #-1"” long.

Eggs: Females lay them mainly aroundgrass roots.

Wireworm (Click Beetle) Adult

Primary Host: Many vegetable crops and sod.

Damage: Feed on seeds and seedlings of corn,beans and peas causing wilting and often deathof the plant. Feed on root crops, reducingmarketability.

Management: Can be detected with baits(untreated grain or potato) buried undergroundbefore planting. Dig up after 10 days and searchfor wireworms. More than 1 per bait stationcan result in economic damage and treatmentwill be necessary.

Biocontrols: Predatory ground beetles and afungus disease may help control them.

Cultural Controls: May be a problem if thefield had been in sod or fallow the year before.Crop rotation may avoid infestation.

Physical Controls: Cultivate at regular intervalsto make it hard for larvae to develop and toreduce egg-laying.


Wireworm Larva

Page designed by J. Kenneth Long, Jr., PA IPM Program; Photo credits: Click Beetle: Marlin E. Rice, Iowa State University, www.ent.iastate.edu; Wireworm larva: Ric Bessin, University of Kentucky, www.uky.edu/.

Documents

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