Isatis. Woad. Isatis tinctoria.
Isatis. Isatis tinctoria L. Woad. Pastel. (Fam. Cruciferae.)—A biennial plant, indigenous to and cultivated in southern and central Europe to central Asia. The leaves have a fugitive, pungent odor, and an acrid, very persistent taste; they have been used in scorbutic affections, jaundice, and other complaints, but are of no value. They were formerly of importance as a source of indigo. The leaves are prepared by grinding them to a paste, which is made into balls, placed in heaps, and allowed to ferment. When the fermentation is at an end, the mass falls into a coarse powder, which is woad.
The Dispensatory of the United States of America, 1918, was edited by Joseph P. Remington, Horatio C. Wood and others.