The root is the portion by which the quill is attached to the body. Although it is a common belief that the porcupine can “throw” its quills, the truth is that the root portion is extremely weak and the quills are easily withdrawn from the body when the barbed tip is driven into an enemy. In fact, any violent movement of the animal may dislodge quills, even though nothing has touched them. There are several well-authenticated accounts of quills having been flipped for several feet in this way, but in each case, it was entirely accidental and through no conscious effort of the porcupine. In other words, the armament of this slow, awkward creature should be considered strictly defensive in every respect. Like the skunk, which can also defend itself most effectively, the porcupine has little apparent fear of its enemies. When threatened with violence it simply brings its head down between the forelegs and turns its rump toward the attacker. With hair and quills erect it resembles a soft furry ball. Appearances are seldom more deceiving! The guard hairs half conceal a spot on the back where a whorl of long quills radiates out in a large “cowlick.” Should any enemy touch these long guard hairs, the muscular tail is thrashed vigorously about in an effort to drive the somewhat shorter but equally keen-pointed tail quills into the attacker. With every attempt at attack from another angle, the porcupine turns so as to present its rump to the enemy. There is one Achilles heel, however, in this otherwise almost perfect defense. It is the unprotected underparts, which at times of danger are always kept pressed against the ground or against a tree trunk. A few carnivores, among them the mountain lion and the fisher, are known to kill the porcupine by flipping it over on its back and tearing it open. Even these large predators seldom escape unscathed, however, and both lions and fishers are known to have died from the effects of quills accidentally taken into the digestive tract. To those who have heard that porcupines live only on bark and always girdle the host trees, it may come as a surprise to find that this is only partly true. Although “bark” is eaten to some extent throughout the year, it is seldom the main diet. When a great deal is taken from one tree, it is gnawed off in an aimless pattern which may or may not girdle the tree. During the spring and summer, a porcupine becomes a browser on tender leaves and twigs in the undergrowth. In autumn and winter, it feeds more on mistletoe and pine needles than on bark. With its low reproduction rate, there is little danger of it eating up our forests, unless its natural enemies are removed. Northern pocket gopher _Thomomys talpoides_ (Greek: thomos, a heap and mys, mouse. Latin: talpa, a mole) Range: From northwestern United States and southwestern Canada to as far south as northern Arizona and northwestern New Mexico.