Garden Pests and Diseases: Worms/caterpillars on my Snow Bush, 1 by MollyMc

MollyMc wrote:
Yep, Snow Bush, those pesky invasive bushes. Well this one isn't invading anything, it's being invaded. These little worms have ate the whole thing and started in on the one 2 plants away from it. They haven't bothered the TiSister, Hollyhocks or other plants in the vicinity.

I bought some Bayer, tree and shrub systemic treatment and put it on my cannas for the leaf rollers, roses for what ails them and also on these. (I have 2 more of these bushes in my herb garden, but won't put the treatment there)

Will the Bayers work on these worms and if so how long will it take to kill them?

Thanks for your help.

:^)))
Molly