How's your Woolly Worm?

Just how good are woolly worms at predicting weather? Woolly worms have 13 bands, each, potentially, of a different color. These correspond to the 13 weeks of winter, from December to March. The darker a band, the colder and snowier the weather. It is as simple as that.

Typically, the bands at the ends of the caterpillar are black, and the one in the middle is brown or orange, giving the woolly bear its distinctive striped appearance. According to legend, the wider that middle brown section is, or the more brown segments there are of the 13 bands, the milder the coming winter will be. Conversely, a narrow brown band is said to predict a harsh winter.

The true woolly bear is the larval form of Pyrrharctia Isabella, the Isabella tiger moth. This medium-size moth, with yellowish-orange and cream-colored wings spotted with black, is common from northern Mexico throughout the United States and across the southern third of Canada. As moths go, the Isabella isn't much to look at compared with some of the other 11,000 species of North American moths, but its immature larva, called the black-ended bear or the woolly bear (and, throughout the South and other places, woolly worm) is one of the few caterpillars most people can identify by name. Woolly bears do not actually feel much like wool, they are covered with short, stiff bristles of hair. In field guides, they're found among the "bristled" species, which include the all-yellow salt marsh caterpillar and several species in the tiger moth family.