Stupid rodents! I have to keep moth balls in the electrical box of my generator to prevent the mice from packing dry grass inside and making a nest. My biggest concern is that they'll chew the wiring in there! Until I discovered the moth ball trick, I was pulling nest material out of the electrical guts of my generator on a daily basis.
I always have mice in the greenhouse and usually, they don't do any damage; but, now and then I get a field mouse. They are the devil! Just one field mouse will destroy hundreds and hundreds of dollars worth of plants each night! I KNOW when one has got in. The damage is very tell-tale. I set traps and as soon as I catch one field mouse, the damage stops.
I don't have trouble with squirrels; but, I do have trouble with chipmunks. They are very mischievious and do a lot of vandalism....just for the heck of it! I recently planted some flats of Disa seedlings and a chipmunk hauled most of the seedlings out of one flat and threw them all over.....no reason....just for fun. I was watering the other day and noticed a chipmunk leaving the propane heater, running along the gas pipe to a shelf of Pleiones and on to the windowsill and along the edge of the vent to the other side of the greenhouse. He went right past me, so I blasted him with the watering hose and knocked him off; out the window. Then, I set up my live trap and caught him the next day. Hopefully, he's not a "homing" chipmunk!