Skip to Main Content
U.S. Forest Service
Caring for the land and serving people

United States Department of Agriculture

Home > Search > Publication Information

  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub
    Author(s): R.A. Progar; M.J. Rinella; D. Fekedulegn; L. Butler
    Date: 2010
    Source: Journal of Appied Entomology. 134(8): 641-646
    Publication Series: Scientific Journal (JRNL)
    Station: Pacific Northwest Research Station
    PDF: View PDF  (1.12 MB)


    In addition to damaging trees, the eastern tent caterpillar is implicated in early fetal loss and late-term abortion in horses. In a field study, we evaluated the potential biological control of the caterpillar using eastern tent caterpillar nuclear polyhedrosis virus (ETNPV), a naturally occurring virus that is nearly species-specific. Egg masses were hatched and second instar larvae were fed virus-inoculated foliage to propagate the virus in vivo. Then, a viral pesticide was formulated at concentrations of 104, 106 and 108 polyhedral inclusion bodies per ml. The pesticide was applied to foliage on which second, third and fourth instar caterpillars were feeding. When the majority of surviving larvae reached the sixth instar, colonies were collected and the surviving caterpillars counted. Mean numbers of surviving caterpillars per treatment were compared via 95% bootstrap confidence intervals. The data indicate second instar caterpillars were highly susceptible to the virus, but only at the highest concentration tested. Third instar caterpillars were also somewhat susceptible to high virus concentrations, while fourth instar caterpillars were fairly resistant. Our data provide the strongest evidence to date that ETNPV can be propagated, harvested, and refined for formulation as a biological control agent for eastern tent caterpillar. Its use on this insect may be merited in circumstances where landowners and managers need to protect trees and horses.

    Publication Notes

    • You may send email to to request a hard copy of this publication.
    • (Please specify exactly which publication you are requesting and your mailing address.)
    • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.


    Progar, R.A.; Rinella, M.J.; Fekedulegn, D.; Butler, L. 2010. Nuclear polyhedrosis virus as a biological control agent for Malacosoma americanum (Lepidoptera: Lasiocampidae). Journal of Appied Entomology. 134(8): 641-646.


    Malacosoma americanum, tent caterpillar, viral pesticide

    Related Search

    XML: View XML
Show More
Show Fewer
Jump to Top of Page