So, if you spot an entirely black caterpillar, it isn’t forecasting an apocalyptic winter!) ( Note: All-black, all-white, or yellow woolly caterpillars are not woolly bears! They are simply different species and are not part of the woolly worm lore.

Often, it is black on both ends with rust-colored segments in the middle, although it may sometimes be mostly black or mostly rust. In terms of appearance, the caterpillar has 13 distinct segments of either rusty brown or black. In others, such as New England and the Midwest, people tend to call them “ woolly bears.” (Worm or not, at least we can all agree that they’re not bears!) Nonetheless, the name “worm” has stuck, at least in some parts of the United States.

Just how true is this weather lore? Learn more about this legendary caterpillar and how to “read” the worm! The Woolly Worm Legendįirst of all, the “ woolly worm” is not a worm at all! It’s a caterpillar specifically, the larva of the Isabella tiger moth (Pyrrharctia isabella). The more black there is, the more severe the winter. Woolly bear caterpillars-also called woolly worms-have a reputation for being able to forecast the coming winter weather. If their rusty band is wide, then it will be a mild winter.

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