I can't tell you what it is but if they were mine I would just let it go this late in the season. They are close to 1st frost anyway and guess and spray programs are hit and miss. They should survive a little chewing and to be honest with you mine look like swiss cheese this time of year what with hail, slugs, and dropping acorns etc. It's the time of year when I tell myself that chewed hosta have character- if it weren't for the chewmarks and blemishes they couldn't be picked out of a lineup.

I've just assumed it was grasshoppers eating some of mine. Typical jagged edged "bites" from the outer edge. But I've never actually seen them.
Rick

Remember that deer love Hostas (the rascals!). During the day the slugs will be on the ground under vegetation, usually.

Probably cutworms. They've been really bad in my yard this year. They take huge chunks out of leaves like you describe. I bought some Ortho bug killer in a powder and just dust it lightly on the plant and around the base. Seems to be working.

Thanks, all! I have seen lots of grasshoppers around, so it may very well be them. I will look for the dust, too. I wouldn't care so much but these are brand new ones I put in last month, and I would at tleast like them to get a good start. One of them has very little leaf left! Not sure of the name of that one, but the Krossa Regal and Night Before Christmas are new, too and taking a beating from the mystery munchers!

Deer are not the problem, I have the BEST deer repellent....a german shepherd! LOL Let's just say he has his territory marked very well, and the deer stay a good distance away!

Linda