Understanding Insect Metamorphosis

• There are more insects on earth than any other animal

• Total number of different types: 30 million?• More than 1,000 kinds of insects in a typical

back yard

FACTOIDS

Understanding metamorphosiscan help you to:

• Properly identify insect pests• Avoid treating non-pest insects• Know where to look for pests• Predict when pests will appear• Select the best products for control

METAMORPHOSIS:striking alteration in appearance,

character or circumstances

SIMPLE COMPLETE

• Little change in appearance or feeding habits

• Immature stages = nymphs; no pupae• Nymphs and adults feed on same food• Examples: Aphids, crickets, whiteflies,

grasshoppers, chinch bugs, roaches

Insects with simple metamorphosis

Insect metamorphosis

and why it matters to you

√√Mole crickets

√√Chinch bugs

ADULTSLARVAE/ NYMPHS

INSECT PEST

Control of insects with simple metamorphosis

• Dramatic difference between immature and adult insects

• Immature stages = larvae• Mature stages = adults• Transformation between larvae and

adult occurs in the pupa• Examples: Butterflies, moths, beetles,

flies, wasps

Insects with complete metamorphosis

COMPLETE METAMORPHOSIS

EGG

LARVA (caterpililar)

PUPA

ADULT

BLACK CUTWORM

COMPLETE METAMORPHOSIS

LARVA(grub)

PUPA CALLOWADULT

ADULT

Black turfgrass ataenius

COMPLETE METAMORPHOSIS

GRUB

ADULT

BILLBUG

COMPLETE METAMORPHOSIS

Leatherjacket

Crane fly

• Soft-bodied• No wings• No sex• Primary activity: food acquisition

• Larvae usually the damaging stage• Examples: caterpillars, grubs, maggots

LARVAE

• Formed by larva in protected location• Little or no movement; no feeding• Larval tissues broken down• Wings, reproductive organs form

PUPAE

Famous pupae:The silkworm, Bombyx mori

• Wings• Usually non-feeding• Hard bodied• Primary activity: mate acquisition

ADULTS

Control of insectswith complete metamorphosis

Larvae are usually targeted because:• Most damaging stage• Can�t fly away• Easier to control

√Oriental beetle

√Japanese beetle

√Green June beetle

√Chafers?√Black turfgrass ataenius

√Asiatic garden beetle

√Sod webworms

√Cutworms & armyworms?√Billbugs & weevils

√Crane flies

ADULTSLARVAEINSECT PEST

Control of insects with complete metamorphosis

Adults are not usually treated, but can be used as an �early warning system�

• Late June/early July chafer flights

• BTA adults on greens, in clippings

• Sod webworms hovering over turf

= ??

Black cutworm adult

Black cutworm larva (caterpillar)

Crane fly larva

= ??

White grub

Sod webworm

Masked chafer

WHITE GRUBS

Masked chafer Black turfgrass ataenius

WHITE GRUBSLARVAE = WHITE GRUBS• Fat & soft bodied; ¼� � 1� long• Usually in �C� shape• 6 legs• Hungry!• Soil insects

• White or transparent/gray with dark head

ADULTS = SCARAB BEETLES• Hard bodied beetles• Dark color• Wings• Usually non-feeding

Products effective for white grubs

trichlorfonDylox

thiamethoxamMeridian

imidaclopridMerit

halofenozideMach 2

CarbarylSevin

AcephateOrthene

FoliageSoilActive IngredientProduct

* water in * 2-3 months activity * preventive

X

X

X

X

X

X

CATERPILLARS

• Soft bodied• Long and thin• Many legs• Darker colored than grubs• Hungry!• Feed on foliage• Adults are butterflies & moths

Products effective for caterpillars

deltamethrinDeltagardhalofenozideMach 2spinosadConserve

λ cyhalothrinScimitar

chlorpyrifosDursban

cyfluthrinTempocarbarylSevinbifenthrinTalstaracephateOrthene

FoliageSoilActive IngredientProduct

* Do not water in * 1-2 wks activity * curative

XXX

XX

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