Chisel-like incisors slice through roots and fibrous bulbs. Porcupines are usually solitary feeders, but groups of two or three individuals, usually one or two adults and their off-spring, are occasionally observed. When attacked or annoyed, the porcupine raises its spines and rattles them vigorously to scare off the predator. They may charge sideways or backward, detaching quills into the attacker. Once the barbed quills enter the skin, they are impossible to remove.
Wounds become infected and eventually kill the attacker.
Although the female produces only two or three litters every year, she comes into season about every 35 days. When she is ready to mate, she raises her rump and tail, and flattens out the rest of her body with quills close to the ground so she does not harm her mate. After 112 days, the female gives birth in her grass-lined burrow. The baby porcupines are covered with bristles and soft quills which harden a few hours after birth. They are fully furred with eyes open.