Click for closeup view

I spied this autumn colored caterpillar making its way across the the pine needles and miniature thyme yesterday.  At first glance I thought it might be our most common banded woolly bear without the black bands encircling both ends, the size of which is said to predict a mild or severe winter. But it was not a banded woolly bear.

There are many species in the “woolly bear” or “woolly worm” family with the characteristic thick bristles that cover the caterpillar’s body. I am undecided which of two woolly bears our orange caterpillar is. Caterpillars can be tricky to identify because of their color variations but I believe this little visitor is either a salt marsh caterpillar, the larva of a Acrea moth (Estigmene acrea) or a yellow bear, the larva of a Virginian tiger moth (Spilosoma virginica).

Click to see a white Virginia tiger moth up close

The Yellow Bear is a fairly common Virginia tiger moth larva that is seen in the fall of the year as it crosses roads and paths seeking a spot for hibernation. The color of the yellow bear can vary from yellow to orange to almost black. The salt marsh caterpillar is common in our area and, in numbers, can be a pest in our vegetable gardens. None are invading our vegetables though. Both larvae develop into lovely and similar tiger moths. I gently picked the caterpillar up (carefully as the bristles can be irritating) and as characteristic of all woolly bears, it immediately curled into a tight ball as a protective measure. I reached down and allowed it to roll from my palm and it quickly made its way over and under the fall leaf litter.

During the summer months, I will often keep a light burning for a couple of hours at night to attract and study a wide variety of moths and insects that settle on the porch wall. The tiger moths are steady visitors, especially the Virginia Tiger Moth with its fuzzy white thorax and its fringed edges on the wings that open to reveal splashes of orange on the abdomen. Because I see so many of the moths at night, I’m leaning toward my visiting woolly bear being a yellow bear caterpillar, however, I’m hoping for a positive ID from someone out there.

Ann Hohenberger, The Garden Club of Gloucester