Dealing with bagworms on evergreen trees plants

Asked May 2, 2013, 3:58 PM EDT

I've got a significant bagworm problem over the last few years, on Douglas Fir and arborvita. I've tried to control by picking off the bags and burning them. I also pulled out a heavily infested evergreen ornamental and burned it. I understand May-June is the best time to spray. I've got an air blast sprayer on a tractor (farm use). The trees are 15-25' tall. Are there some formulations eg of Sevin or permethrin that could be used? And how do I know when to spray? It would be good if the pesticide were not toxic to bees. Lots of bumblebees in the yard nearby. Thanks.

Lehigh County Pennsylvania

1 Response

Hello, and thanks for using the Ask an Expert system.
Ohio State University offers a good fact sheet on the biology and control of evergreen bagworms that should answer your questions. You can access the fact sheet at http://ohioline.osu.edu/hyg-fact/2000/pdf/2149.pdf It provides invormatiion on various control methods as well as methods for figuring the timing of sprays.