Most marten live in the Interior Alaska forests of stunted black spruce trees and bogs. Lighter-colored marten tend to have grayish brown tails, while darker animals have dark brown tail fur. The fur around the muzzle varies from gray to light brown with a short dark line extending up the forehead from the corner of each eye. The marten's throat and upper chest are usually pale or buff or deep orange. The ears are erect and rounded.
Males are considerably larger then females.
The tail accounts for nearly a third of the marten's total length. Marten have sharp, non-retractable claws which they use for climbing as well as for holding their prey. Large furry paws allow the marten to travel easily over deep snow. Mating pairs are temporary and the males may have several mates at the same time. Mating occurs in July and August.