WOODRUFF (AS. wudurofe, wuderofe, from wudu, widu, wood + *rofe, of uncertain meaning, possibly ruff), Asperula. A genus of about 75 annual and perennial herbs of the natural order Rubiaceæ. The sweet woodruff (Asperulaodorata) is common in shady woods in all parts of Europe. The plant when dried has an agreeable fragrance, similar to that of dried vernal grass. It forms an agreeable herb tea, and enters into the composition of the popular May drink of the Germans. Dyer's woodruff (Asperula tinctoria), a native of Europe and of Siberia, is a perennial whose root is used in Dalmatia and elsewhere instead of madder, but is less productive.