Wood sorrel

Description

Oxyria digyna (mountain sorrel, wood sorrel, Alpine sorrel or Alpine mountain-sorrel) is a species of flowering plant in the buckwheat family (Polygonaceae). It is native to arctic regions and mountainous parts of the Northern Hemisphere. Mountain sorrel is a perennial plant with a tough taproot that grows to a height of 10 to 30 cm (4 to 12 in). It grows in dense tufts, with stems that are usually unbranched and hairless. Both flowering stems and leaf stalks are somewhat reddish. The leaves are kidney-shaped, somewhat fleshy, on stalks from the basal part of the stem. Flowers are small, green and later reddish, and are grouped in an open upright cluster. The fruit is a small nut, encircled by a broad wing which finally turns red. Forming dense, red tufts, the plant is easily recognized. Oxyria digyna grows in wet places protected by snow in winter. Oxyria (from Greek) means "sour". Mountain sorrel is common in the tundra of the Arctic. Further south, it has a circumboreal distribution, growing in high mountainous areas in the Northern Hemisphere such as the Alps, the Sierra Nevada, and the Cascade Range. It typically grows in alpine meadows, scree, snow-bed sites and beside streams. On the coast of Norway, the pollen of this plant has been found in peat bogs that are 12,600 years old, indicating that it must have been one of the first plants to colonise the area after the retreating ice age glaciers. Deer and elk favor the plant. Oxyria is a genus of plants in the family Polygonaceae with three accepted species as of March 2019. It has a circumboreal distribution. Species of Oxyria are perennial herbaceous plants or weakly shrubby. They may have rhizomes. Their stems are erect, variably branched. Undivided leaves are present both at the base of the plant and on the stems. They are arranged alternately and have stalks (petioles). The ocrea is tubular and membranous. The inflorescences are terminal, paniclelike or racemelike, borne on stems (pedunculate). Individual flowers are either bisexual or unisexual, with four greenish to reddish brown tepals. The fruits are in the form of achenes with broadly winged margins.