Q: I saw a black woolly bear caterpillar. I’ve heard this means a bad winter. Is this true?

• Sally from Berlin Center

A: Every year I get questions about these intriguing caterpillars. Mostly, the questions relate to the ability of these caterpillars to predict our winter weather. As the tale goes — the black band on the woolly bear caterpillar will expand to predict bad winters with heavy snows and be almost nonexistent in the fall before a mild winter.

So, the answer is — it is just a tall tale. It never fails that I get into an in-depth conversation each fall answering questions and explaining how this is good fun, but it really means nothing. It is, though, a great lesson in entomology and the natural world around us.

In most years, caterpillars with varying widths of that black band are found throughout much of the Midwest. Woolly bears are the caterpillar stage of medium-sized moths known as tiger moths. There are eight or more species of woolly bear caterpillars. The most common in Ohio are the Banded Woolly Bear, the Yellow Woolly Bear, the Salt Marsh Caterpillar and the Giant Leopard Moth.

The one most commonly mistaken for foretelling our winters is the Banded Woolly Bear, of which the adult is the Isabella Moth. The coarse hairs of the banded woolly bear are black at both ends and reddish-brown in the middle. The black bands can be wider on some caterpillars, leading some to talk about the black bands expanding. Research has debunked this legend by showing the amount of black varies with the age of the caterpillar and the moisture levels in the area where it developed.

Then, there is the all-black caterpillar many of us see this time of year. This is not a woolly bear caterpillar at all. It is most likely the caterpillar of the giant leopard moth — a.k.a. Great Leopard Moth, which looks all black until it curls up and then you can see red stripes on its sides.

So, why do we suddenly see these caterpillars this time of year? October and November are the months when these woolly bear caterpillars search for a location to winter over. They usually hide under plant debris. Their annual search is why you see them crawling over everything this time of year.

Enjoy them while they’re still around — and have a good time shooting the breeze about their apparent ability to predict the winter weather.

To learn more about these fascinating caterpillars, go to http://go.osu.edu/woollybear

Eric Barrett is the Ohio State University Extension educator for agriculture and natural resources in Mahoning County. Call 330-533-5538 to submit questions to our clinic. Live clinic hours are 9 a.m. to noon Mondays and Thursdays. Visit go.osu.edu/mahoningclinic for details.