About a week ago my hostas started being decimated by something. The information on GardenWeb seemed to indicate that the major damage was being caused by cutworms because the eaten areas were huge. I scratched the surface of the earth around some of the affected hostas and did indeed find a few cutworms. I treated the affected hostas by sprinking cornmeal around the hostas being careful to avoid the petioles.
My husband applied diatomectous earth around our house foundation yesterday.
I was outside around 10 pm with flashlight in hand to check on my hostas. I found only 3 cutworms in my hosta beds. They were about an inch long and I almost mistaked them for dry litte twigs. One hid on top of the leaf at the base and the others were on the petiole.
I had applied the ammonia drench to my hostas in the spring. I found no slugs on my hostas. I did, however, find baby earwigs under a couple of my hostas. I also find a lot of white spiders in my hostas and wonder whether they are beneficial or harmful.
I don't know whether the cornmeal worked. I just wanted to report back about my experience. I will try to be more scientific in my approach next year.