What is inside this folded, browned sugar maple leaf?
This is a Maple Trumpet Skeletonizer caterpillar’s home! This pale yellow caterpillar uses its frass (excrement) and silk to build a hideaway from predators. The tube grows wider as the caterpillar (and its frass) get larger, forming a trumpet-like shape. The trumpets are nestled into a leaf folded with silken threads. The caterpillars feed, and thus skeletonize, the leaf from the protection of the trumpet.
In the fall, the caterpillar drops to the ground, creates a silken cocoon between two leaves, and pupates. The brown and tan speckled moth emerges in June, mates, lays eggs singly on maple leaves, and the trumpet-building begins anew!
