According to legend, the two-inch long, bristly-haired wooly bear caterpillar has the reputation for being able to forecast the coming winter weather.
Sometimes called a wooly worm, it is one of the most recognizable insects in North America. They are black at both ends and rust colored in the middle.
Its 13 bands are indicative of the 13 weeks of winter. In the fall, if there are more rusty bands than black, it indicates a mild winter; more black bands indicate a harsh winter.
Position of the bands makes a difference. If the head has more dark bands, the beginning of winter will be severe.
Most scientists discount the woolly bear predictions as folklore. Even so, in 1948, the curator of insects at the American Museum of Natural History in New York City became intrigued and intended to prove the legend.
Every fall, for eight years, he collected caterpillars, calculated the average number of rusty color segments, forecast the coming winter weather, and sent the results to a friend at The New York Herald Tribune where it was published, making the wooly worm famous.
Entomologists suggest the wooly worm might indeed reveal the weather… from last year, not the upcoming winter. Their coloring is based on how long the caterpillar has been feeding, its age, and species.
The healthier the growing season, the bigger it will grow, resulting in narrower rusty bands in its middle.
Their bristly hairs may look ominous but they are not poisonous. The caterpillars do not inject venom. They do not cause disease. On the other hand, they can cause itching and dermatitis on sensitive skin.
When picked up or disturbed they curl into a tight ball with the wiry hairs on the outside and “play dead.” By appearing frightful, they may avoid being eaten by some predators.
Officially, the woolly bear is the larval form of the Isabella tiger moth, Pyrrharctia Isabella. They feed on most wild plants.
In the fall, after they leave the host plants, they look for a cool, dark place underneath leaf litter to overwinter. They can survive in temperatures, as low as minus ninety degrees Fahrenheit because their body produces a kind of antifreeze in the form of glycerol alcohol.
They have even been known to endure an entire winter completely frozen. When spring arrives, they spin a fuzzy cocoon and transform into the Isabella Tiger Moth.
Since 1978, there has been a Woolly Worm Festival in Banner Elk, North Carolina (although it was canceled this year with a pledge to return in 2021).
Contestants race their caterpillars up three-foot strings in 25 heats. Races continue until the final winner becomes the official winter forecaster for North Carolina High Country.
The champion worm trainer is crowned and rewarded. Other festivals are held in Kentucky and Pennsylvania. Surprisingly, the results are usually about 85 percent correct.
Wilma Durpo is a naturalist, nature writer and author. She resides in Waynesville and regularly appears as a nature columnist in local publications.