Florence from Lynbrook, New York writes
Unfortunately spraying for bagworms now is pointless. You can manually control bagworms by simply plucking them off of the infested trees and dropping them into a bucket of soapy water or squishing them. This control method is most useful during fall, winter and early spring, before the eggs inside the bag have hatched. It is important to start control methods before a major infestation occurs. Once the bagworms have matured and have formed the "bag" most chemical control methods will no longer work. Using a product like Talstar P before the eggs have hatched in the spring and early summer will most beneficial.
Answer last updated on: 08/10/2014