Got a shock the other day when I realized that my four 20' mature Spartan Junipers were under attack by at least a thousand bagworms. This is serious stuff, and you can't play around with them - they can kill a 20' Juniper in a couple of days. I already had large brown areas. I went to the store and got Spectracide in the hose-end sprayer and worked the Spartans over. I had noticed some of my local wild birds raiding the bags/cocoons for the worms, and I was concerned about them (actually humming 'Bye, Bye, Birdie while I sprayed - just kidding!), but it had to be done. So far they seem okay (after 48 hours). The Spectracide worked BIG TIME! The morning after treatment, only a few bags were still moving. The first time I saw the infestation and approached the junipers, all the bags were squirming, and it looked like some kind of horror movie. There will be at least one follow up treatment, and I now know to hit them every July 4th. Purple Finchs nest in them every spring but they're long gone by July. I don't usually use such a powerful and broad-spectrum insecticide. I even had to rush to the store to get it as I didn't have anything on hand to deal with the infestation, but I guess its good to have the 'H-bomb' sometimes. I highly recommend this product for bagworms or any other serious situation you might have. Its great for treating mulch around the foundation or for ticks in the back yard.