Host trees

Forest tent caterpillars eat the leaves of many broad-leaved trees and shrubs. Their favorite food in Northern Wisconsin is aspen (poplar), oak, and birch in forests, and marshal seedless ash and flowering crab in town. They won’t feed on red maple or conifers. All the defoliation is caused by caterpillars; the adult moths do not eat leaves.

Aspen trees (right) were completely defoliated by forest tent caterpillars, whereas nearby red maple (left) was left untouched