Spring And Fall Cankerworms (and other inchworms and loopers)

Ohio State University Extension Fact Sheet

Entomology

1991 Kenny Road, Columbus, Ohio 43210-1090

Spring And Fall Cankerworms

(and other inchworms and loopers)

HYG-2558-95

David J. Shetlar
There are numerous cankerworms, or inchworms, that attack deciduous trees and shrubs. The Spring cankerworm, Paleacrita vernata (Peck), and Fall cankerworm, Alsophila pometaria (Harris), are the most common pests encountered but the elm spanworm, Ennomos subsignaria (Hubner), and linden looper, Erannis tiliaria (Harris), also have periodic outbreaks.

These cankerworms, inchworms, loopers and spanworms occur throughout North America. The fall cankerworm is also known from Montana, Colorado, Utah and California while the spring cankerworm territory extends southwards into Arkansas and Texas. Other inchworms, loopers and spanworms occur in western states.

Plants Attacked

Both fall and spring cankerworms feed on a wide variety of trees including apple, ash, beech, elm, hickory, linden, maples and oaks. The elm spanworm attacks elms, hickory, ash and oaks as well as a variety of other broadleaf trees. The linden looper is common on basswood, linden, apple, maples and oaks and other trees.

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Keith L. Smith, Associate Vice President for Ag. Adm. and Director, OSU Extension.

TDD No. 800-589-8292 (Ohio only) or 614-292-1868