Where have all the caterpillars gone?
December 16, 2001

Where are those brown and black, furry caterpillars going as they make their way across rocks and sidewalks this time of year?

The caterpillars are looking for a snug place to crawl under to spend the winter. These are Woolly Bear caterpillars---the larval form of the Isabella Tiger Moth. When handled the caterpillar protects itself by curling up in a tight ball, "playing dead."

This bundle of bristles is not easy to pick up. Birds that eat caterpillars usually do not like the fuzzy ones.

If you can get the caterpillar to unroll, you will discover that it has 13 divisions, but the last two are joined to look like one. On the front three segments are six legs to tell that it's an insect---with shiny "patent leather" claws. Other "make-believe" legs are used to cling to leaves and twigs.

Its small eyes cannot see very well, so it rears up and feels for a place to go while feeding.

Though the body looks like it is covered with fur, a closer look will show the bristles are arranged in little rosettes closely packed on each segment.

The amount of black (on both ends) and reddish brown (in the middle) varies with each caterpillar. Some believe that the weather of the approaching weather can be told by "reading" the color bands of the Woolly Bear.

It has been found, however, that past rather than future weather causes the coloe.

Woolly Bears hatched in September hibernate under boards, logs and cracks in rocks where they can surl up and hide for the winter. They emerge in early spring. Sometime they can be seen crawling over snowy ground. They eat fresh grass, dandelions, clover, plantain, spinach and other early green things.

They soon make a cocoon out of silk interwoven with their own fur.

It is a "fat" felt-like cocoon and looks much too small to hold such a large caterpillar. late in May, a lovely Isabella moth will come out of the cocoon.

This moth, like most others, is night-flying and is attracted to easy-to-find white flowers that are strong-scented, in their search for nectar.

You may still find Wooly bears out and about with the mild weather we have been having here in east central Wisconsin.

Your second search will come early next summer. What flowers in your garden are white? Which ones open up at night?