Rose slugs. Turn over the leaves and squint at the underside as you look for tiny, tiny green wormlike critters. Squish with your fingers -- or toss into the lawn if your stomach is quesy.

Usually all one has to do is WAIT a couple weeks--for the good bugs to show up and gobble up the rose slugs, but they usually arrive before that much damage gets done. Have you been spraying the roses with insecticides in the past? They will kill off the good bugs also. If so, you may have to wait until next year for the good bugs to return.

The manual method is the only way I know to keep them under control while you wait for the good bugs. Maybe some other posters will have some other suggestions.

Good luck.

Kate

Yep looks like you have some hungry rose slugs...
I have seen small birds and predatory wasps eat them once in awhile but that's about it around here.

I have no idea about your area though...