Caterpillars that Attack Oak Trees

The following question was sent to the P&PDL diagnosticians here at Purdue University:

Question: I would like more information on caterpillars that attack oak trees and their description.

Answer: There are a several caterpillars that attack oak trees. Examples:

1. Orangestriped oakworms -- Approximately 55 mm long, black in color with four yellow-orange stripes running the length of the body. They also have short spines protruding from the sides of the body.

2. Yellownecked caterpillars (see photo) -- Approximately 30 mm long, black in color with 7-8 yellow stripes running the length of the body. They have a black head with a yellow-orange neck. Sides of the prolegs are orange to yellow. White hairs arise from body. There is also a yellow-red color phase (all descriptions apply except for the black body).

3. Redhumped oakworms -- Approximately 40-50 mm long, brilliantly colored with stripes consisting of yellow, white and black. The head is red. On the tail end, the caterpillar has a reddish-orange bump, hence the name redhumped oakworm.

-Corey Gerber, Insect Diagnostician