Forest Pest Insects in North America: a Photographic Guide

Pinkstriped oakworm

Anisota virginiensis (Drury) (Lepidoptera: Saturniidae)

Orientation to pest

Pinkstriped oakworm, Anisota virginiensis (Drury), is a native moth that feeds on foliage of oaks (Quercus) and other hardwoods. It occurs throughout the eastern United States and southern Canada. Young larvae feed in groups, skeltonizing leaves. Older larvae are less gregarious and consume all but the main veins of leaves. Larvae can be found April through September depending on the climate, with one generation per year in its northern range and up to three generations per year in its southern-most range. This insect is common but not abundant and is usually considered a minor pest to landscape trees where damage to larger trees is often limited to defoliation of single branches. However, small trees can be completely defoliated.

Hosts commonly attacked

Pinkstriped oakworm feeds primarily on oaks (Quercus), but it is also reported from chestnut (Castanea), hazel (Corylus), maple (Acer) and birch (Betula).

Distribution

This species occurs in southern Canada and the eastern United States, as far west as Manitoba and Texas.

Images of pinkstriped oakworm

Male and female adults of pinkstriped oakworm mating Pennsylvania Department of Conservation and Natural Resources - Forestry Archive, Bugwood.org 768x512 / 1536x1024
Eggs of pinkstriped oakworm James Solomon, USDA Forest Service, Bugwood.org 768x512 / 1536x1024
Young larvae of pinkstriped oakworm Lacy L. Hyche, Auburn University, Bugwood.org 768x512 / 1536x1024
Figure 1. Adults of pinkstriped oakworm, Anisota virginiensis: male and female mating Figure 2. Eggs of pinkstriped oakworm Figure 3. Young larvae of pinkstriped oakworm
Close up of pinkstriped oakworm larva James Solomon, USDA Forest Service, Bugwood.org 768x512 / 1536x1024
Pupa of pinkstriped oakworm Lacy L. Hyche, Auburn University, Bugwood.org 768x512 / 1536x1024
A group of pinkstriped oakworm caterpillars defoliating an oak branch James Solomon, USDA Forest Service, Bugwood.org 768x512 / 1536x1024
Figure 4. Close up of pinkstriped oakworm larva Figure 5. Pupa of pinkstriped oakworm Figure 6. A group of pinkstriped oakworm caterpillars defoliating an oak branch

Important biological control agents related to this pest species

In Manitoba, five species of larval or pupal parasitoids have been recorded from this species: Houghia sternalis (Coquillett), Lespesia anisotae Webber, and Winthemia datanae (Tns.) (all Tachinidae); and Habronyx magniceps (Cresson) and Hyposoter fugitivus (Say) (both Ichneumonidae).

Web links for information on pinkstriped oakworm

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