The band on a woolly bear doesn't predict the winter. It's closer to being a record of the summer that's coming to a close. The caterpillar starts out mostly black, and the rust-colored band widens with each molt. So a wide band means an older caterpillar that's been eating longer, and that usually means a long, warm growing season with plenty of food. That caterpillar isn't hurrying to build a cocoon. It's looking for a place to spend the entire winter as a caterpillar. Under leaf litter, inside a log, beneath loose bark. And when the cold arrives, its heart stops, its gut freezes, and ice forms in the spaces between its cells while cryoprotectants in its tissues keep the cells themselves from rupturing. It stays that way for months. In spring it thaws out, feeds for a short while, spins a cocoon out of silk and its own bristles, and emerges as an Isabella tiger moth. Most people have never connected the two. Its Arctic cousin takes this to an absurd place. Up in the high Arctic, the summer is so short that the caterpillar can only feed for a few weeks a year, so it freezes and thaws over and over, for roughly seven years, before it has enough stored energy to pupate at all. It spends nearly its whole life frozen. It's active for about 5% of it. So the practical part: the woolly bear crossing the road in October is house hunting. It needs leaf litter, a log, a brush pile, a corner of the yard nobody touches. If you rake every leaf and bag it, you threw the house away with it.