Other common names.—Curled dock, narrow dock, sour dock. (Fig. 5.)
Fig. 5.—Yellow dock (Rumex crispus L.). First year’s growth.
Range and habitat.—The species most commonly employed in medicine is the yellow dock, a perennial introduced from Europe and now found throughout the United States as a troublesome and very persistent weed in cultivated as well as waste ground, among rubbish heaps, and along roadsides.
Description.—The deep, spindle-shaped root sends up an erect, angular, and furrowed stem about 2 to 4 feet high, leafy, branching near the top, and bearing numerous elongated clusters of inconspicuous flowers. The leaves are lance-shaped, acute, with the margins strongly waved and crisped. The lower leaves are obtuse or heart shaped at the base, from 6 to 8 inches in length, and are borne on long stalks, while those nearer the top are narrower and shorter, being only 3 to 6 inches long, on short stems or stemless.
From June to August the yellow dock puts forth, interspersed with leaves, its many long dense clusters of green, drooping groups of inconspicuous flowers placed in circles around the stem.