Sedum laxum

Zika, Peter F., Wilson, Barbara L., Brainerd, Richard E., Otting, Nick, Darington, Steven, Knaus, Brian J. & Nelson, Julie Kierstead, 2018, A review of Sedum section Gormania (Crassulaceae) in western North America, Phytotaxa 368 (1), pp. 448-450 : 448-450

6. Sedum laxum (Britton in Britton & Rose 1903: 29) Berger (1930: 451)

Gormania laxa Britton in Britton & Rose (1903: 29). Cotyledon brittoniana Fedde in Schumann & Fedde (1904: 828). Echeveria gormanii Nelson & Macbride (1913: 476). Sedum jepsonii Butterfield (1936: 7) .

Type: — UNITED STATES. Oregon: Josephine Co., Waldo, 4 June 1884, Thomas Howell s.n. (lectotype, designated by Clausen [1942: 37], NY; isolectotype, US).

Notes: — Sedum laxum plants were often relatively tall. Rosette leaves were fairly dense, and obovate, thin or thick, glaucous or green, and truncate to notched. Stem leaves were ascending and oblong or elliptic, crowded or not, sometimes thick, decurrent or not. Sepals were about a third or less as long as the petals. Petals were erect and bright pink with white margins (sometimes all white), slender, attenuate, usually erect. Anthers were dark red, aging black.

Sedum laxum was traditionally divided into as many as six generally allopatric subspecies. We recognized S. laxum subsp. eastwoodiae , and S. laxum subsp. flavidum , both tetraploid and with more obtuse petals, at the species level; see discussions under those taxa. We recognized as subspecies the diploids S. laxum subsp. heckneri with suborbicular, usually reflexed stem leaves, and S. laxum subsp. laxum , with stem leaves longer than wide, ascending, and sometimes thickened. Ranges of the two subspecies were discrete, with subsp. heckneri found east and south of subsp. laxum .