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..
S. ternatum Michx. Fl. Bor. Am. 1: 277. 1803.
Perennial by rootstocks, tufted, stem creeping, flowering branches ascending, 3'-8' high. Lower leaves and those of the sterile shoots flat, obovate, entire, 6"-12" long, sometimes 9" wide, rounded at the apex, cuneate at the base or narrowed into a petiole, verticillate in 3's; upper leaves oblanceolate or oblong, alternate, sessile; cyme 2-4-forked, its branches spreading or recurved in flower; flowers rather distant, often leafy-bracted, about 5" broad; petals linear-lanceolate, acute, white, nearly twice the length of the oblong obtuse sepals; follicles 21/2" long, tipped with the slender style.
On rocks, Connecticut to New Jersey, Georgia, west to Indiana, Missouri, Tennessee and Michigan. Also escaped from gardens to roadsides in the Middle and Eastern States. Ascends to 3000 ft. in Virginia. Iceland-moss. Three-leaved stonecrop. April-June.
Sedum Nevii A. Gray, Man. Ed. 5, 172. 1867.
Densely tufted, glabrous, stems spreading or decumbent, flowering branches ascending, 3-5' high. Leaves of the sterile shoots very densely imbricated, spatulate or obovate, narrowed or cuneate at the base, mostly sessile, rounded at the apex, entire, 3"-6" long, 1"-2" wide, the lower ones smaller; leaves of the flowering branches spatulate or linear-oblong, alternate; cyme about 3-forked, its branches usually recurved in flower; flowers close together, 3"-4" broad; petals linear, acuminate, longer than the sepals; follicles about 2" long, widely divergent, tipped with the short style.
Sedum stoloniferum. Gmel., a perennial species, with opposite obovate-cuneate crenate leaves and pale rose-colored petals twice as long as the calyx, occurs on roadsides and in fields in Maine and Nova Scotia. Native of the Orient.