Things You'll Need
Instructions
Obtain a good field guide with color illustrations or photos from your local library, bookstore or nature center.
Go on the Internet which features many good sites, such as Iowa State University's Bug Guide or Discover Life. Some sites even allow you to upload your own personal images of caterpillars you want identified and experts will get back to you with the specific species.
Identify caterpillars by visual features including main body color, body pattern, hair density or tufts, and distinct features, such as tails (which are sometimes split), horns, knobs, lashes and spines. By identifying these features, you can easily hone in on their identities.
Identify caterpillars beyond just the visual elements. Caterpillars can also be identified by knowing body length, the type of plant they feed on and the location where found.