I like Busters idea (gun), but seriously I had a problem with deer. I strung 50 lb. fishing line acrross all paths around my grow, at several hieghts in each spot. The deer of course could break through it, but they don't. It freaks them out and they find a different way. Then just for overkill, I hung bloodmeal in nylons and sprayed liquid fence. No more problem.