Forest Tent Caterpillar

Natural Habitat

Found throughout North America in deciduous forests, mixed woodlands, and urban areas with host trees.

Diet & Feeding

Broadleaf deciduous trees, including ash, birch, maple, and especially aspen and oak. They are voracious leaf-eaters.

Behavior Patterns

Unlike other tent caterpillars, they do not build actual silk tents; instead, they spin silk mats on trunks and branches where they congregate. They often undergo cyclic population outbreaks every 10-12 years.

Risks & Benefits

They can cause large-scale defoliation of forests, though trees usually survive. While not poisonous, their hairs may cause mild skin irritation in sensitive individuals. They serve as a vital food source for many bird species and predatory insects.

Identified on: 4/13/2026