Cardamine bellidifolia is a tiny tufted herb in the mustard family (Brassicaceae) that grows in rocky situations and tundra in the mountains. This species has four-petalled white flowers typical of the mustard family and long, erect fruiting siliques. This species is a glabrous perennial herb that grows from a taproot, reaching up to 15 cm high when in flower but is typically much smaller and very easily overlooked. The stems may be erect or decumbent. The leaves are ovate, entire and simple (distinguishing it from other species of Cardamine in Denali), mostly in a basal rosette, fleshy, and up to 30 mm long. The flowers are in an umbel-like raceme. Flowers are perfect, with four white (rarely pale purple) petals that are 3-5 mm long and sepals up to 2 mm long. The fruits (siliques) are erect, up 3.5 mm long and 1.5 mm wide. In Denali, Cardamine bellidifolia could potentially be confused with Eutrema edwardsii, another member of the mustard family with four-petalled white flowers and ovate leaves, but that species lacks the compact basal rosette of leaves and is usually considerably larger and growing in more lush meadow vegetation than Cardamine bellidifolia.
Cardamine bellidifolia is perennial and generally flowers around early to mid-summer.
Cardamine bellidifolia is monoecious with bisexual flowers. Flowers are potentially insect-pollinated, but its reproductive biology has not been studied. It reproduces by seed, no vegetative reproduction is known. Seed production in Svalbard, Norway, is abundant, and is by the explosive opening of the valves (Flora of Svalbard 2016).
The adults of a mite, Aceria drabae (Eriophyidae), produce galls on alpine bittercress leaves and the larvae feed on the leaves when they emerge (Biological Records Centre 2008).
Species in this genus are known for their juicy, succulent leaves high in vitamin C. The lower elevation species were used to prevent scurvy. However, because alpine bittercress is so small, is usually found in small scattered populations, is slow growing, and is found at high elevations, it is unlikely to be good source for this purpose.
Alpine bittercress is a circumpolar arctic-alpine species. In Alaska, this species occurs occasionally in suitable habitats throughout the state. Similarly, alpine bittercress occurs in hills in mountains across Denali on both sides of the Alaska Range crest.
Alpine bittercress is the highest elevation species of the three species of Cardamine growing in the park. Most of its 100 occurrences were at elevations between 1100 m and 1300 m with an average of 1219 m. There were slightly more occurrences on north-facing slopes (37%) than on south-facing slopes (29%). It favors moderately high inclines, with an average of 24 degrees on north-facing slopes and 18 degrees on south-facing slopes.