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..
Plants mostly villous, deep green. Stems early decumbent, 4'-12' long; leaves often numerous; leaflets pale or glaucescent beneath, ciliate; peduncles sometimes slightly longer than the petioles; sepals linear or nearly so, 3"-4" long, pubescent at the base and tip; corolla deep chrome-yellow, 7"-10" broad; petals pubescent without; styles copiously villous; capsules stout, columnar, S"-7i" long.
On rocky hillsides and in open woods, Kentucky to Alabama. June-Nov.
Xanthoxalis recúrva (Ell.) Small, admitted into our first edition, is not definitely known to occur in our range.
Oxalis cymosa Small, Bull. Torr. Club 23: 267.
1896. X. cymosa Small, Fl. SE. U. S. 668. 1903.
Plants normally tall, bright green. Stem usually erect, 6'-4° high, branched above, often villous, reddish or brown; leaves 9'-18" broad, on petioles 1 1/2' - 3' long; leaflets broader than long, sharply notched; petiole-bases scarcely dilated; flowers yellow, in dichoto-mous cymes; pedicels erect, or ascending, 3"-4" long, more or less villous; sepals lanceolate or narrowly elliptic, 2"-3" long, finally spreading; petals obtuse, or emarginate, 4"-5" long; capsule slender, columnar, 5"-7" long, gradually narrowed to the summit; seeds obovoid-oblong, 3/4" long, with nearly continuous ridges.
Oxahs recurva Trel. Mem. Bost. Soc. Nat. Hist. 4: 89.
1888. Not Ell. 1821. Oxalis grandis Small, Bull. Torr. Club 21: 474. 1894. Xanthoxalis grandis Small, Fl. SE. U. S. 668. 1903.
Plants stout, glabrate below or villous, bright green. Stem erect, 1°-4° tall, simple, or nearly so; leaves 1 1/2'-3' broad; leaflets usually unequal, often with a brown margin, more or less ciliate; petioles villous, hardly dilated at the base, 2'-6' long; flowers yellow, in dichotomous cymes; pedicles 5"-7" long, erect, or spreading; sepals unequal; ovate, or oblong, 2"-3' long, often ciliate at the apex; petals rounded at the apex, 6"-8" long; capsule stout, ovoid, or ovoid-oblong, 3"-5" long, seeds ovoid or obovoid, 1" long, with broken transverse ridges.