Malacosoma americanum
Lepidoptera: Lasiocampidae
Identification
• The caterpillar is dark-colored with a whitish stripe down the back
bordered by orange, black, and blue stripes. Full-grown larvae are 2" long.
(a)
• Caterpillars live colonially in a silk tent in a branch crotch and
emerge at various times during the day to feed. (b)
• The adult is a moth with a 1-2" wingspan and is tan with 2 white
stripes on the front wings.
• The eggs are brown and are laid in a collar about 1/2" wide around
small twigs and branches. (c)
Damage
• Caterpillars hatch at spring leaf emergence, eat the leaf margins,
and commonly defoliate small trees.
• Caterpillars attack primarily crabapple, hawthorn, cherry, mountain-ash,
and other trees and shrubs in the rose family.
Management
• Remove silk tents at night and on rainy days when the caterpillars
are inside.
• Remove egg masses anytime from July to March.
• Spray attacked foliage with a bacterial insecticide.