Question
I read your answer about bagworms and found it very informative. I'd like a little more explanation if you don't mind.  Instead of spraying the entire tree with one of the products you mentioned, isn't there something I can spray on the bagworms individually?  Or will spraying the tree prevent more bags to form?  Also, I picked off the ones I could reach and threw them in my trashcan.  Obviously this was not the correct thing to do.  Do I need to dig them out of my trashcan, or can I spray something in my trashcan, as it's full of clippings and other garden debris.  Thank you so much.

Answer
Do not worry about the ones you put into the trash. They could crawl back out but the trash should be picked up before that time. IF you want put them in a plastic ziplock bag and this will stop them  from crawling and also the heat will kill the caterpillar in the bag. The caterpillars move around on the tree and that is why we usually recommend that all foliage be sprayed. But you can spray the bags as you see them and not have to spray all the tree. The spray control the population and does not really prevent future infestations except that the number of moths are greatly reduced and this prevents some defoliation.

Insecticide Sprays Stomach insecticides are very useful for control of bagworms. Remember that the plant foliage is to be thoroughly covered because the larvae are protected from contact by being in the silk bag. Again, early sprays against young larvae are more effective than later applications. Products registered for bagworm control are: acephate (Orthene), bifenthrin (Talstar), carbaryl (Sevin), chlorpyrifos (Dursban),  diazinon, dimethoate (Cygon), malathion, nicotine sulfate, and pyrethrum.