Update for anybody who cares. Thank you all so much for your comments and time! I was able to rid both my plants of rose slugs and just in time. I reburied the cane and added more mulch around the base. It's been blooming all summer long so it seems pretty happy.
I'm still a little iffy on how to winterize the single cane. I don't want to cut that whole thing down to 18 inches right? Just winterize as is? My plan is 6 to 8 inches of mulch around the base, chicken wire circle filled with pine needles.
