Stellaria alaskana is a delicate alpine herb that grows in slide rock and talus, mostly in the mountains north of the Alaska Range crest in Denali, forming diffuse to compact clumps among the rock shards. This species has flowers with deeply cleft white petals. Plants grow 3-10 cm tall from elongate rhizomes. Leaves are oppositely arranged, compressed at the stem base, lanceolate-elliptic in shape, glabrous, acute, and relatively thick. The flowers (1-2) are typically solitary and produced in axils of scariousbracts. The five petals are white and cleft nearly to the base, appearing like ten petals at first glance. The sepals are linear-lanceolate, prominently veined and longer than the petals. There are 10 stamens and 3 styles. Fruits are a capsule, opening by six-valves. This species can be distinguished from other species of Stellaria by its short habit, unbranched inflorescence and the flower stalks emerging from scariousbracts instead of green leaves.
This perennial species flowers mid-summer.
Stellaria alaskana is monoecious and insect pollinated. Seeds are probably gravity and wind disseminated.
Stellaria alaskana is endemic to Alaska and southwestern Yukon, where it is considered rare. In Alaska, S. alaskana only occurs in the arc of the Alaska Range southeast to the Mentasta and Wrangell mountains and into Kluane National Park, Yukon. A small population exists in the Brooks Range off the Dalton highway. In Denali, S. alaskana is not uncommon, occurring primarily along the north slope of the Alaska Range and outer foothills, but also occurs south of the range along the Denali fault (upper Cantwell Creek and Bull River).
Stellaria alaskana is an alpine species that is found at plot elevations from 853 m to 1787 m, with an average site elevation of 1323 m. It prefers steep slopes (greater than 20 degrees), and slightly prefers north facing slopes.