Also known as Yellow Woollybears, the yellow color of the caterpillar ranges from pale, butter yellow to a rusty, orange-yellow. Some are so pale they are more white than yellow. Others are so dark, they appear almost black. The youngest ones are a yellow-green and sparsely covered in black hairs. These are not venomous, stinging hairs, but they may cause irritation for some people. As they mature, the hairs become denser and more bristly, covering the body in clustered tufts that have longer hairs in the center of them. Despite the woolly part of its name, the caterpillar looks less like a clump of wool and more like a pipe cleaner. The hairs are shed and used as part of the cocoon, and perhaps this is where its resemblance to wool is best displayed.
Eggs are round and yellow and laid in a large group on the underside of a leaf. After hatching, the caterpillars feed on almost any kind of foliage. Because of their diverse array of host plants, they are not a pest for any single plant species and are common in many parts of their range. Look for them while hiking through woodlands and forests, or even while strolling through the backyard.
The map above showcases (in blue) the states and territories of North America where the Virginian Tiger Moth Caterpillar may be found (but is not limited to). This sort of data can be useful in seeing concentrations of a particular species over the continent as well as revealing possible migratory patterns over a species' given lifespan. Some species are naturally confined by environment, weather, mating habits, food resources and the like while others see widespread expansion across most, or all, of North America.*NOTE: States/Territories shown above are a general indicator of areas inhabited by the Virginian Tiger Moth Caterpillar. Insects generally go where they please, typically driven by diet, environmental changes, and / or mating habits.