The three types of insecticide that effectively control bagworm include Btk (Bacillus thuringiensis kurstaki), which is packaged as Dipel and Thuricide, among others; cyfluthrin, packaged as Tempo and other Bayer products; and spinosad, packaged as Conserve. Each type requires careful attention to the packaging instructions for safe use.Continue Reading
Bagworm control is important, as the insects have a way of destroying the evergreen trees that they infest. Timing is crucial; the best time to apply bagworm insecticide is the end of June, with a second application a couple of weeks later. In August, the bagworms, in their caterpillar phase, seal their bag up, stop eating and turn into pupae in preparation for emerging as moths. After they stop feeding, there is no reason to spray any insecticides, because they will not make their way to the bagworms.
In their caterpillar phase, bagworms feed throughout the summer. This is the ideal time for spraying. Once the bags are large and hanging on the trees, the best plan is to take the bags off the trees. That cuts down on the number of caterpillars that emerge and start to feed the following year. In late spring, when the bagworms hatch, the caterpillars climb up high in the tree, sending out silk strands that catch in the breeze and carry the caterpillars to a new tree, repeating the process until they end up on a tree they can feed on.Learn more about Pest Control