Its length averages 15 cm (5.9 in) long with a 5-cm tail, and it weighs about 39 g (1.4 oz).

They are found on moist rocky slopes in eastern Canada and the northeastern United States.

They make runways through the surface growth and shallow burrows.

They feed on grasses, mosses, underground fungi and berries (especially bunchberry), and also sometimes on caterpillars.

Predators include hawks, owls, snakes and small carnivorous mammals.