This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol1", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Rumex persicarioides L. Sp. PI. 335. 1753.
Annual, pubescent, pale green; stem rather stout, erect and simple, or diffusely branched, I°-3° high, or sometimes spreading or creeping, very leafy. Leaves lanceolate, or oblong, 1'-12 long, narrowed at the base, or sometimes cordate, or sagittate, acute at the apex, the margins undulate and more or less crisped; panicle simple or compound; racemes erect, leafy-bracted, mostly interrupted; flowers densely whorled; pedicels slender, 1-1 1/2 times as long as the calyx-wings, jointed at the base; calyx very small; wings oblong, 1" long, with 1-3 bristles on each margin, each bearing an ovoid or oblong callosity; achene less than 1" long, pointed, reddish, smooth, shining, its faces convex, its angles slightly margined.
On sandy shores, New Brunswick to Virginia, extending across the continent to British Columbia, south in the interior to Kansas and New Mexico and on the Pacific Coast to California. Has been confounded with R. maritimus L. of the Old World. July-Oct.