INDIANA — As spring temperatures begin to rise across the Hoosier state, the Indiana Department of Natural Resources (DNR) is advising landowners to keep a close eye on their trees. The eastern tent caterpillar (Malacosoma americanum), a native defoliating insect, has begun its annual emergence, signaled by the appearance of distinctive silken “tents” in the forks of tree branches.
While the sight of these webs can be alarming, experts say the impact is often more aesthetic than terminal for Indiana’s forests and landscapes.
The life cycle of the eastern tent caterpillar is closely tied to the arrival of spring.
…
- Early Spring (Late March – April): Caterpillars hatch from overwintered egg masses and immediately begin spinning silk tents in the crotches of branches for protection.
- Mid-to-Late Spring (May): The larvae continue to feed on emerging leaves, growing up to twice their current size—reaching roughly 2 to 2.5 inches in length.
- Early Summer (June…