I never thought it looked like a slug until you pointed it out. I guess I'm too used to looking at caterpillars. I was showing my trainee some just hatched Sulphur cats yesterday and she was like, "How do you even see them?" I guess you just get used to it. Also, my optometrist hooked me up with some great contacts. My glasses are pretty awesome, too. Without them, I'd get lost in my house.
In plague years (as I call them), those Tussock Moths will absolutely cover the house with their cocoons. Oh, and the shed, and the trailer, and the boat, etc. Best to use a pressure washer but we can only do that at certain times of year since I get other caterpillars that like to build on the house. Usually, it's the Monarchs. Plus, we use a bleach solution and I think some kind of detergent and I don't want that near the caterpillars or plants. My dad and brother just washed the house a couple of weeks ago. I told them to do it then or wait all year because I will not put my caterpillars in harm's way!