About Dryas octopetala subsp. oxyodonta (Juz.) Hultén
This taxon is Dryas octopetala subsp. oxyodonta (Juz.) Hultén. It has woody, tortuous stems with short horizontal rooting branches. Its leaves are hairless and smooth on the upper surface, and covered in dense white woolly hairs on the lower surface. Flowers grow on stalks 3–10 cm (1–4 in) long, and each flower has eight creamy white petals – this feature gives the parent species its specific epithet octopetala. The style remains attached to the mature fruit, and is covered in white feathery hairs that act as a wind-dispersal agent. The feathery hairs of the seed head first appear twisted together and glossy, before spreading out into an expanded ball that is quickly dispersed by the wind. Dryas octopetala, the parent species of this subspecies, is widespread across mountainous regions, where it is generally restricted to limestone outcrops. Its range covers the entire Arctic, as well as the mountains of Scandinavia, Iceland, the Alps, the Carpathian Mountains, the Balkans, the Caucasus, and isolated locations in other areas. In Great Britain, it grows in the Pennines of Northern England, at two sites in the Snowdonia region of North Wales, and more widely across the Scottish Highlands. In Ireland, it occurs on The Burren and a small number of other sites. In North America, it is found in Alaska, where it grows most often on previously glaciated terrain, and extends through the Canadian Rockies as far south as Colorado in the Rocky Mountains. It grows in dry locations where snow melts early, on gravel and rocky barrens, and forms a distinct heath community on calcareous soils. Dryas octopetala is cultivated in temperate regions as groundcover, or as a plant for alpine or rock gardens. It has been awarded the Royal Horticultural Society's Award of Garden Merit. Its leaves are occasionally used to make herbal tea.
