It's been an impressive year for tent caterpillars, and the silken communal nests of our common species, Malacosoma americanum, have been unusually common in the crotches between branches of cherry trees and other hardwoods, especially members of the Rose family. When the larvae emerge in April and spin their shelters, the tents are small, but as the caterpillars grow on a diet of fresh leaves, the nurseries and the kids grow rapidly. They do, however, like company, so after a day's foraging, they tend to "return to its safety to digest their food," notes caterpillar maven David L. Wagner in his must-have field guide, Caterpillars of Eastern North America. "The tent provides protection from natural enemies and serves as a greenhouse on cool days, allowing the caterpillars to raise their body temperatures above the ambient, facilitating digestion and other metabolic processes." And even when the exceedingly pretty youngsters are outside, they occasionally enjoy the lepidopteran equivalent of a group hug.