Effects of Mimic(R) bioinsecticide on the species diversity of non-target forest Lepidoptera in an operational spruce budworm (Lepidoptera : Tortricidae: Choristoneura fumiferana Clem.) suppression program in northwestern Manitoba

Thumbnail Image
Saunders, Diana E.
Journal Title
Journal ISSN
Volume Title
A new biochemical insecticide, Mimic [R] (Dow Agrochemicals), has recently been registered in Canada for the control of lepidopteran defoliators in forest ecosystems. The active ingredient, tebufenozide, mimics the insect molting hormone, 20-hydroxyecdysone, in larvae of some species of Lepidoptera inducing a premature molt, causing death. To date there has been only one published study on the effects of an operational spray program that has addressed the effects of Mimic[R] on non-target Lepidoptera in hardwood forest, and none in the boreal forest. Butler et al. (1997) found significant reductions in richness and abundance of non-target, larval macrolepidoptera of a hardwood forest following Mimic[R] application for control of gypsy moth, Lymantria dispar (L.). In 1999 and 2000, Manitoba Conservation applied Mimic[R] to areas of the boreal forest in northwestern Manitoba as part of an operational spruce budworm suppression program. In 2000 and 2001, moths and larvae were collected from twelve study sites within the spray area to determine the effect of Mimic[R] on spruce budworm and non-target Lepidoptera. Three 70 m2 plots were within spray blocks sprayed once with 70g Al in 2.0 L/ha in June of 1999; three 70 m2 were within spray blocks sprayed once in June of 2000 and six were in unsprayed areas...