How do you kill bagworm insects?

To kill bagworm insects, you can use a combination of physical removal and insecticides. Handpicking the bags off affected plants is effective for small infestations. For larger infestations, applying a targeted insecticide, such as Bacillus thuringiensis (Bt) or a pesticide containing spinosad, can be effective when the larvae are actively feeding in late spring to early summer. Always follow label instructions and take care to minimize impact on beneficial insects.