Monographs Details: Lotus nevadensis var. douglasii (Greene) Ottley
Authority: Isely, Duane. 1981. Leguminosae of the United States. III. Subfamily Papilionoideae: tribes Sophoreae, Podalyrieae, Loteae. Mem. New York Bot. Gard. 25 (3): 1-264.
Description:Distribution and Ecology - Range as given in key. Open coniferous forest, grassy slopes, prairies, river banks, roadside cuts, occasionally serpentine; at lower elevations with sagebrush; often abundant. Ca. 1500-5000 ft. May-July (-Aug.).
Discussion:H. decumbens Benth. (1829) non Poir. (1813); L. incanus Dougl. ex Hook. (1831) pro syn.; Syrmatium decumbens (Benth.) Greene (1887); L. douglasii Greene (1890); Anisolotus decumbens (Benth.) Thornb. (1915); L. nevadensis var douglasii (Greene) Ottley (1944).
L. douglasii var congestus Ottley (1923); L. nevadensis var congestus (Ottley) Ottley (1944).
L. leonis Eastw. (1937).
Lotus nevadensis vars douglasii and nevadensis merge clinally, as previously stated by Jepson (1936), and I have mapped some of the intermediates separately. Ideal var douglasii of Washington to northern California has a corolla 8—10 mm and calyx 5-6 mm, the slender teeth commonly subequal to the tube. The flowers maintain their yellow color, and the leaflets are usually 8-14 mm. Var nevadensis, south approximately of Lake and Placer cos, has a promptly reddening corolla 5-8(-9) cm, and calyx 3-5 mm with teeth commonly 1-1.5 mm, and the leaflets are often small, 5-10 mm. Populations in northern California are intermediate, the corolla usually exceeding 8 mm, and the plants having the aspect of var douglasii, except that the calyx and teeth are shorter. Some of these, with short stems, and congested umbels, are Ottley’s var congestus. I have assigned most of these northern California plants to var douglasii, but they are not exactly that variety further north and east.