Imperial Moth Caterpillar (Eacles imperialis). One of our largest caterpillars. The last instar, or larval stage, can grow to be 5.5 inches long. As an adult the Imperial Moth is mighty big too. Its wingspan ranges from 3 to 7 inches.

They’re found from Quebec and Ontario to as far south as Argentina, from the Atlantic coast, to the Rocky Mountains. These caterpillars eat the leaves of Oaks, Maples, Sassafras, Sweetgum, Bald Cypress, Hickory, Cedar. And these are just their favorites. They can be found nibbling the leaves of many other trees. Fortunately for the trees, these caterpillars don’t show up in large numbers and don’t present a threat to any of the trees they dine on.

See all those hairs on these caterpillars? They can irritate skin. There are also barbs that can cause a rash. It’s my policy to leave caterpillars be. I don’t pick them up, just to be safe. Not just the Imperial Moth Caterpillar but all caterpillars. I think they’re happier that way too.