Northern Prairie Wildlife Research Center
Also called "wild begonia", "wild hydrangea", and "sour greens", veined dock occupies most North Dakota counties west of the Missouri River, as well as a few scattered locations as far east as Grand Forks County. Elsewhere, the plant occurs from southern British Columbia and Saskatchewan south to New Mexico and California at elevations up to 8,500 ft.
Veined dock is perennial from a wide-spreading rhizome. Leaves have long stalks and are about four inches long. The flowers are small and there are no petals, normally the most colorful parts of a flower. Instead, three small sepals expand tremendously at maturity into gorgeous, rose-colored structures nearly two inches wide. These heavily-veined structures (called valves) protect the small, light-brown achenes (seeds) that are only about 3/16" long. Ten to twenty of these valves form huge clusters in the upper branches and give the plants a striking appearance.
Look for veined dock from April through July on sandy native prairies and along roadgrades. Livestock seem to avoid the plant and create favorable conditions for it, as larger numbers of plants are usually found where grazing pressure is heavy. The leaves and stalks of many of the docks are used as potherbs and the roots for various medicines, but I found no references to human uses of veined dock.
Veined dock is a member of the cosmopolitan buckwheat family (Polygonaceae) which contains about 900 species, including a few cultivated for ornament and several that are nuisance weeds. Buckwheat and rhubarb are the only important economic species. Rumex is the ancient Latin name for the docks and venosus means "veiny" in botanical Latin. There are about 150 species of Rumex worldwide; most occur in the temperate zone. Veined dock was first described for science in 1814 by Frederick Pursh, who was the first to publish on the many new plants collected by the Lewis and Clark Expedition of 1804-1806.