Laboratory and field studies on the effects of Bacillus thuringiensis on non-target lepidoptera

Abstract

Bacillus thuringiensis (B.t.) is one of the insecticides considered effective for suppression of gypsy moth infestations, and it is considered to one of the most selective in terms of its effects on other insects. Although B.t. is touted to be "environmentally safe", there is a paucity of field data to support this claim, particularly as it relates to the effects of B.t. on native Lepidoptera. Increasingly, lepidopterists, environmentalists, the general public, and certain forest managers have expressed concerns that B.t. may, in fact, have a significant negative impact on non-target Lepidoptera. Although it has been stated that most lepidopterous larvae are present in the field long after B.t. applications (and therefore are not affected by early season gypsy moth spraying), and that the larvae of most Lepidoptera would be unaffected by B.t. because they are not canopy feeders, this may not be true for a significant number of species. In fact, we know far too little about the larval stages of most native Lepidoptera to safely make the above generalizations.

Citation

Peacock, John; Talley, Stephen; Williams, Taylor; Reardon, Richard. 1992. Laboratory and field studies on the effects of Bacillus thuringiensis on non-target lepidoptera. Northeastern Area State and Private Forestry, Gypsy Moth News. 28: 7-8.