Cankerworm (Inchworm)
Scientific Name: Alsophila pometaria (Fall Cankerworm) or Paleacrita vernata (Spring Cankerworm)
Order & Family: Order: Lepidoptera, Family: Geometridae
Size: Larvae typically grow to about 1 inch (25 mm) in length.
Natural Habitat
Deciduous forests, orchards, and urban areas containing host trees such as oak, maple, and elm.
Diet & Feeding
Larvae are generalist feeders that consume the foliage of various deciduous trees and shrubs.
Behavior Patterns
They move with a distinctive looping or "inching" motion. When disturbed, they often drop from tree branches on silk threads; they undergo complete metamorphosis with larvae appearing in early spring.
Risks & Benefits
They are major defoliators of shade and forest trees which can stress the plants; however, they serve as a critical food source for migratory birds during the spring nesting season.
Identified on: 5/17/2026