BUTTON SNAKEROOT (Liatris or Laciniaria), a genus of North American plants of the family Compositae, comprising about 3o species found chiefly in the central and eastern United States and southern Canada. Various species, because of their showy flowers, are also called blazing star. They are erect, per ennial, mostly unbranched herbs, with the stem usually rising from a globular tuber, whence the name button snakeroot. The leaves are narrow, often rigid, and sometimes strongly dotted; the rose-purple or rarely white flowers are borne in hemispherical or cylindrical heads, usually in long dense spikes or narrow ra cemes. Noteworthy examples are the scaly blazing star (L. squarrosa), I ft. to 2 ft. high, found from Ontario to South Dakota south to Florida and Texas; the handsome blazing star (L. elegans), 2 ft. to 3 ft. high, native to dry soil from Virginia to Arkansas and southward; the large button snakeroot (L. scariosa), sometimes 6 ft. high, found from Maine to Manitoba and south ward to Florida and Texas ; the dense button-snakeroot (L. spi cata), called also gay-feather, colic-root and devil's-bit, 2 ft. to 6 ft. high, with blue-purple or white flowers, found from Mas sachusetts to Wisconsin and southward: and the prairie button snakeroot (L. pycnostachya), 2 ft. to 5 ft., with very numerous rigid leaves and a long, very dense spike of purple flowers, native to prairies in the Mississippi valley.