Green - Shmeen. It's much more humane to shoot paper. Only someone who was around during the pet rock craze can truly understand how docile and defenseless those free ranging stones are. Sure, some of them can be a little rough around the edges. Sure, some of them may attack the soles of your boots or even nip at bare feet, but they only do that in self defense. They're basically harmless and will all smooth out after a millennium or two. Shooting them unnecessarily is just cruel. Please visit the PETS website (PEOPLE FOR THE ETHICAL TREATMENT OF STONES) and learn more about our friends on the ground.