Two species of hornworm damage tomato plants in Virginia, the tobacco hornworm, Manduca sexta (Linnaeus) and the tomato hornworm Manduca quinquemaculata (Haworth) (Insecta: Lepidoptera: Sphingidae).
Both species are green with diagonal lines on sides and prominent horn on rear end. They can be up to 4 inches long.
Common Host Plant(s)
Tomato, eggplant, tobacco, and pepper.
Theses caterpillars feed on leaves and green fruit. They are typically found on the upper portions of the plant. Since they consume 90% of the foliage just before they pupate they seem to appear “overnight”. This is not actually true; the smaller stages of the caterpillars did limited feeding that was quickly covered by regrowth. They in fact were on the same plant all along.
Throughout Virginia and the United States.
Hand pick worms, but do not destroy caterpillars with cocoons, leave in garden to continue biological control.
Bacillus thuringiensis, Bt, will control the caterpillars but must be applied when they are less then ½ inch long.
Apply a labeled insecticide, following all instructions and precautions. Insecticides must also be applied when the caterpillars are less then ½ inch long.
University of Florida fact sheet: common name: tobacco hornworm scientific name: Manduca sexta (Linnaeus) (Insecta: Lepidoptera: Sphingidae), common name: tomato hornworm scientific name: Manduca quinquemaculata (Haworth) (Insecta: Lepidoptera: Sphingidae),
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