Plan the perfect garden with our interactive tool →

What Insecticide Kills Bagworms?

Bagworms are caterpillars that feed on the foliage of plants such as conifers, junipers, oaks and arborvitae. Spray the bagworms while they are still actively eating, for the best control. Use an insecticide such as permethrin, spinosad or trichorfon, according to the University of Illinois. After the pupate stage, spraying has no affect in killing them.

Insecticide Kills Bagworms?

Bagworms affect many species of evergreens and several deciduous trees, constructing baglike shelters from which they feed on foliage. These include acephate, bifenthrin, Bt, carbaryl, chlorpyrifos, diazinon, lambda-cyhalothrin and malathion. Insecticide approvals change over time. Because of this, if you are using an insecticide against bagworms, the Penn State University Extension recommends applying it early, while the larvae are small and most susceptible.

Garden Guides