Also referred to as the Black swallowtail, Carrot Caterpillar, or Celeryworm.
Green with yellow and white spotted black band; up to 2 inches long. Two orange "horns" just behind the head are projected when the caterpillar is disturbed. This caterpillar is the larva of the black swallowtail butterfly.
Common Host Plant(s)
Carrot, celery, parsley, dill and parsnip.
Chews leaves and stems, destroys tops. Seldom numerous enough to reduce yield.
Throughout United States.
After the black swallowtail butterfly emerges from its cocoon in the spring it deposits eggs on plants in the carrot family. This insect overwinters as pupa on the host plant. There are two or more generations annually.
Handpicking these caterpillars is usually sufficient.
Bacillus thuringiensis, or Bt, will work, but its results are not quickly observable. It is not necessary to wait before harvesting after an application of Bt.
Treat with a registered insecticide if cultural control fails, follow all label instructions regarding wait period between application and harvest.
Virginia Cooperative Extension materials are available for public use, reprint, or citation without further permission, provided the use includes credit to the author and to Virginia Cooperative Extension, Virginia Tech, and Virginia State University.
Issued in furtherance of Cooperative Extension work, Virginia Polytechnic Institute and State University, Virginia State University, and the U.S. Department of Agriculture cooperating. Edwin J. Jones, Director, Virginia Cooperative Extension, Virginia Tech, Blacksburg; M. Ray McKinnie, Administrator, 1890 Extension Program, Virginia State University, Petersburg.
April 25, 2011