Caterpillars not winter predictors
Q. Will we be seeing lots of woolly bear caterpillars this year? Is it true they will predict the winter (I’m hoping we won’t be as cold this year!)
Marge from Youngstown
A. Fall is synonymous with woolly bears. For years they have been touted as the forecasters of winter.
Many of us are interested in predicting the winter. The most interested people are those in Vermillion, Ohio, home to the country’s largest festival to promote, forecast and have fun with pet woolly bears (http://go.osu.edu/woollyfestival).
This fun and interesting caterpillar is black with orange/red/brown bands. We see them on sidewalks, skittering across the roads, in our garages, as they seek out shelter for the winter.
They are actually the larval form of the Isabella Tiger Moth (Pyrrarctia Isabella), a pretty, yet nondescript 2-inch brown moth.
They feed on herbaceous plants, then search out sites to overwinter – under bark, in/under rocks and logs.
They produce a cryptoprotectant (“antifreeze”) to protect their bodies as they freeze solid in the winter.
Some in the arctic have survived up to 14 winters.
In spring they awaken, pupate in a silk cocoon, and emerge as moths to mate and die.
The rule of thumb is the ends are black, and the band in the middle is brown, red or orange. Actually, the banding depends on the instar, as there are a number of molts, with more black on the younger, to less black on older larvae.
The wider the band, the milder the winter, is the belief. Narrow bands (more black) is said to mean more severe winters.
There is no scientific basis for this belief.
They are members of the tussock family (with tufts), but they are harmless (no toxins, reactions, etc.).
As for winter prediction, researchers at the University of Illinois tell us the difference in the width of the black bands is simply due to age and wetness.
Usually, the younger caterpillars have more black hair due to more moisture in the fall.
Some of them spend their entire life as either brown or black.
More on the caterpillars: http://go.osu.edu/woollybears
More on winter weather predictions: http://go.osu.edu/woollywinter
Stephanie Hughes is an OSU Extension master gardener volunteer. Call the office hot line at 330-533-5538 to submit your questions. Clinic hours are Mondays and Thursdays from 9 a.m. to noon through October.