This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol3", 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..
Perennial by slender rootstocks; stems glabrous, branched near the summit, very leafy to the top, 6°- 10° high. Leaves sessile, entire, linear or nearly filiform, or the lowest lanceolate, remotely dentate and short-petioled, rough with mucronate-tipped papillae, especially on the lower surface, acuminate, 4'-16' long, 1"- 4" wide, the upper all alternate and 1- nerved, the lower commonly opposite; heads numerous, about 2' broad, terminating slender branches; involucre nearly hemispheric, its bracts linear-subulate to lanceolate, acuminate, squarrose, ciliate; disk purple or brown; receptacle convex, its chaff entire, or toothed, slightly ciliate; rays 10-20; achenes ob-long-obovate, glabrous, 2 1/2" - 3" long, 2-4-awned.
On dry plains, Missouri and Nebraska to Colorado and Texas. Sept.-Oct.
Helianthus atrorubens L. Sp. Pl. 906. 1753.
Perennial; stems hirsute below, often minutely pubescent above, branched at the summit, 2°-5° high. Leaves hirsute on both sides, or canescent beneath, mostly thin, ovate or ovate-lanceolate, acutish, contracted near the base into margined petioles, sometimes subcordate, dentate or crenate-dentate, 4'-10' long, 1'- 4' wide, the lower opposite, the upper few, distant, small, mainly alternate; heads not numerous, slender-pedun-cled, about 2' broad; involucre hemispheric, its bracts oblong to obovate, obtuse, ciliolate, appressed; disk purple; recptacle convex, its chaff acute, entire, or 3-toothed; rays 10-20; achenes obovate, truncate, finely pubescent, about 2" long; pappus usually of 2 lanceolate awns.
In dry woods, Virginia to Florida, west to Ohio, Missouri, Arkansas and Louisiana. Aug.-Oct.
H. scaberrimus Ell. Cot. S. C. & Ga. 2: 423. 1824. H. rigidus Desf. Cat. Hort. Paris, Ed. 3, 184. 1829.
Perennial; stems simple or little branched, hispid or scabrate,1°-8° high. Leaves thick, coriaceous, serrate or serrulate, very scabrous on both sides, 2-7' long, ¥-2' wide, acute at the apex, narrowed at the base, the lower ovate or ovate-oblong, petioled, the upper lanceolate or oblong-lanceolate, sessile or short-petioled, all opposite, or the uppermost bract-like and alternate; heads solitary or few, 2'-3' broad; involucre hemispheric, its bracts ovate, acute or obtusish, ciliate, appressed; disk purple or brown; receptacle convex, its chaff obtuse; rays 15-25, light yellow; achenes more or less pubescent, oblong-obovate; pappus of 2 broad scales or of 2-4 stout awns.
Prairies, Illinois to Minnesota, Iowa, Kansas, Georgia and Texas. Aug.-Sept.