"Eastern Woodrats are common in wooded areas with dense understories, in hedgerows, and in rocky outcrops. Their dens are occupied by a succession of individuals, each one adding more sticks and other material to the collection. Dens average 2-3 feet in height. They offer protection from some predators, but not from snakes and weasels, which can follow the Woodrat into its den. The Woodrats store edible and non-edible material in their dens, and it is not known why the inedible materials are kept. Woodrats are born nearly naked, with their eyes and ears closed, and they immediately attach to one of the four teats on their mother's underside. They remain attached to the nipples, only rarely letting go, for three to four weeks."

Links:
Mammal Species of the World
Click here for The American Society of Mammalogists species account