Forest Tent Caterpillar

Natural Habitat

Deciduous forests, woodlands, and urban areas across North America.

Diet & Feeding

Leaves of broadleaf trees, especially aspen, gum, oak, maple, and birch.

Behavior Patterns

Unlike other tent caterpillars, they do not build silk tents; instead, they spin silken mats on trunks and branches where they congregate at rest. They are known for cyclical outbreaks every 6 to 16 years.

Risks & Benefits

Risks: Can cause significant defoliation of trees during outbreaks, which may stress or kill already weakened trees. Benefits: They are a food source for many birds and predatory insects, and their droppings return nutrients to the soil.

Identified on: 4/2/2026