Polygonum bistorta

from The Collaborative International Dictionary of English v.0.48

Snakeweed \Snake"weed`\, n. (Bot.)
   (a) A kind of knotweed ({Polygonum Bistorta}).
   (b) The Virginia snakeroot. See {Snakeroot}.
       [1913 Webster]

from The Collaborative International Dictionary of English v.0.48

Adderwort \Ad"der*wort`\, n. (Bot.)
   The common bistort or snakeweed ({Polygonum bistorta}).
   [1913 Webster]

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