Dock, herbaceous plant of genus Rumex, family Polygonaceae (buckwheat); most docks are perennial. Some species are called sorrels. About 150 species occur worldwide; of 22 in Canada, about half are native. In the Northern Hemisphere, most docks are common weeds. The greenish flowers at the top of the plant turn reddish-brown at maturity. The seeds are smooth, brown and 3-sided. Curled dock (R. crispus), one of the 5 most widely distributed plants in the world, is a troublesome weed in disturbed land in all provinces. Its long, narrow leaves have crumpled, wavy margins. Broad-leaved dock (R. obtusifolius) occurs in damper, partly shaded sites in eastern Canada and BC.

Across the prairies field dock (R. pseudonatronatus) is more common than curled dock. Sheep sorrel (R. acetosella) occurs on impoverished lands in all provinces. This slender plant, 15-30 cm high, has sour, acid-tasting leaves, each with 2 basal lobes on a long stalk. The larger, "narrow-leaved" garden sorrel (R. triangulivalvis) is abundant along the lower St Lawrence. Leaves of sorrel species can be eaten like spinach. Natives valued leaves and taproots for medicinal properties.

See also Aboriginal Uses of plants.