This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", 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..
Annual, light green, stem slender, erect, striate, usually much branched, 1°-3° tall, the branches very slender, divergent or ascending. Leaves thin, green on both sides, lanceolate or oblong-lanceolate, acute or acuminate at the apex, narrowed at the base, slender-petioled, l'-2 1/2' long, the lower sinuate-dentate or nearly all of them entire; flowers in slender terminal and axillary spikes; calyx-segments broadly oblong, obtuse, scarious-margined, not keeled, or scarcely so in fruit, herbaceous, nearly covering the utricle; styles short; seed horizontal, readily separating from the pericarp, black, shining; embryo completely annular.
Annual, glabrous or very nearly so, light green, stem stout or slender, erect, grooved, branched, 1o-3° tall. Leaves thin, green on both sides, broadly triangular-hastate, sinuate-dentate or the upper entire, mostly obtuse at the apex, truncate or abruptly narrowed at the base, slender-petioled, 1'-4' long and nearly as wide, the uppermost sometimes very small, oblong or lanceolate and acute; spikes slender, axillary to the upper leaves and in terminal panicles; calyx \" wide, its segments keeled in fruit, and nearly enclosing the utricle; pericarp easily separable from the seed; seed horizontal, shining; embryo completely annular.
In woods and thickets, South Dakota and Nebraska to Montana and Nevada, south to New Mexico, Arizona and northern Mexico. July-Sept.
Chenopodium urbicum L. Sp. Pl. 218. 1753.
Annual, green or but slightly mealy, stem commonly stout, erect, branched or simple, channeled, 1°-3° tall. Leaves hastate or triangular-ovate, acute at the apex, truncate subcordate or abruptly narrowed at the base, stout-petioled, coarsely and irregularly dentate or the uppermost entire, the larger 3'-5' long; spikes in terminal and axillary narrow erect panicles, the upper longer than the leaves; calyx 1/2" broad, its segments oblong, obtuse, herbaceous, not keeled and not entirely enclosing the fruit; styles short; seed horizontal, rather firmly attached to the pericarp, its margins rounded; embryo a complete ring.