Entireleaf mountain-avens

Dryas integrifolia Vahl (Rosaceae), entire-leaved mountain-avens or white dryad, is a low, mat-forming evergreen subshrub of Arctic and high-boreal North America, Greenland, and adjacent areas, ranging from Alaska across the Canadian Arctic to Newfoundland. Slender, woody, much-branched stems trail across the substrate forming dense cushions a few centimetres high. The small, leathery, alternate leaves are oblong to elliptic with mostly entire (sometimes obscurely toothed) margins, 5-15 mm long, dark glossy green above and densely white-tomentose beneath. Solitary, erect, eight-petalled white flowers about 2 cm across are borne on slender pedicels well above the foliage. Following flowering, the persistent styles elongate into a feathery silvery plume, aiding wind dispersal of the achenes. The species is a pioneer coloniser of calcareous gravels, frost-heaved soils, fellfields, tundra ridges and recently deglaciated terrain, and is an important nitrogen-fixing partner with actinorhizal Frankia symbionts.