Arctous alpina
Arctous alpina var. japonica on Mt. Iide, Fukushima Prefecture, Japan.
Conservation status
Secure  (NatureServe)[1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Asterids
Order:	Ericales
Family:	Ericaceae
Genus:	Arctous
Species:	A. alpina
Binomial name
Arctous alpina (L.) Nied.
Synonyms
Comarostaphylis polifolia Arctostaphylos alpina

Arctous alpina (syn. Arctostaphylos alpina), the alpine bearberry, mountain bearberry or black bearberry, is a dwarf shrub in the heather family Ericaceae. The basionym of this species is Arbutus alpina L..

Description

Arctous alpina is a procumbent shrub usually less than 6 inches (15 cm) high with a woody stem and straggling branches. The leaves are alternate and wither in the autumn but remain on the plant for another year. The leaves are stalked and are oval with serrated margins and a network of veins. They often turn red to scarlet in autumn. The flowers are in groups of two to five, white or pink and urn-shaped and about 3 to 5 mm (0.12 to 0.20 in) long. They have five sepals, five fused petals with five small projecting lobes, ten stamens and a single carpel. The fruits are spherical, 9 to 12 mm (0.35 to 0.47 in) long, initially green, then red and finally glossy black and succulent when ripe. This plant flowers in June.^[2][3]

Distribution and habitat

Arctous alpina has a circumpolar distribution. It is found at high latitudes, from Scotland east across Scandinavia, Russia, Alaska, Northern Canada and Greenland. Its southern limits in Europe are the Pyrenees and the Alps, in Asia, the Altay Mountains and Mongolia, and in North America, British Columbia in the west, and Maine and New Hampshire in the east.^[4] Its natural habitat is moorland, dry forests with birch and pine and hummocks covered in moss at the edges of bogs.^[3]

Ecology

Arctous alpina forms a symbiotic relationship life with fungi which supply it with nutrients such as phosphorus. The berries are appreciated by birds.^[3]