Monographs Details: Lotus purshianus var. purshianus
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 of the species except for that of var helleri above.
Discussion:Trigonella americana Nutt. (1818); L. americanus (Nutt.) Bisch. (1840) non Veil. (1825); Hosackia americana (Nutt.) Piper (1906); Acmispon americanus (Nutt.) Rydb. (1913).
L. sericeus Pursh (1814) non Moench (1794); A. sericeus (Pursh) Raf. (1832); Hosackia sericea (Pursh) Trelease ex Branner & Cov. (1888).
H. purshiana Benth. (1829); L. purshianus (Benth.) Clements & Clements (1914).
H. unifoliolata Hook. (1833). L. (?) unifoliolatus (Hook.) Benth. (1837).
H. elata Nutt. (1838); Acmispon elatus (Nutt.) Rydb. (1913).
H. elata var glabra Nutt. (1838); H. americana var glabra (Nutt.) G. S. Torrey ex Rob. (1916); L. americanus var minutiflorus Ottley (1923); L. americana var glabra Ewan ex Jeps. (1936); L. purshianus var minutiflorus (Ottley) Ottley (1944); L. purshianus var glaber (Nutt.) Munz (1958).
H. floribunda Nutt. (1838); A. floribundus (Nutt.) Hell. (1914).
H. pilosa Nutt. (1838); H. americana var pilosa (Nutt.) Piper (1906); A. pilosus (Nutt.) Hell. (1913).
H. mollis Nutt. (1838) non Greene (1886); A. mollis Hell. (1913).
A. gracilis Hell. (1913).
A. sparsiflorus Hell. (1913).
A. glabratus Hell. (1913).
A. aestivalis Hell. (1913).
In Pacific and contiguous states: Ocean beaches upwards to coastal chaparral or grass to mountain forests; open woodlands and borders, meadows, arroyos, creek borders and beds, roadsides and other disturbed and ruderal (-cult) areas and weedy; most commonly spring-moist, sandy soils; frequent and plentiful, sometimes carpeting the ground. 0-7800 ft. May-Aug. (-Oct.). In Central states: short grass plains and prairie fragments; also post oak woodland and ruderal in s; usually moist soil, most frequently in sand; of sporadic occurrence n, common and abundant s. Ca. 400-5200 ft. May-June (-July) (s); June-Aug. (-Sept.) (n).
Despite the vast range occupied, there is less exomorphic diversity among Lotus purshianus var purshianus of the central United States than in the Pacific states. Fernald (1950), Gleason (1952), Small (1933), Fassett (1939) and Isely (1951), all report var purshianus further east than tabulated on Map 51. Its former presence is recorded by 19th century collections from Wisconsin, Illinois, and Indiana where it was undoubtedly native before the destruction of the prairies. Reports such as, “N.Y. and Va.” (Fernald, 1950), are probably of waif introductions, the seeds of L. purshianus being occasional contaminants in agricultural seed.
Possibly, Lotus purshianus has unexploited forage usefulness, J. R. Larsen (1976), a range conservationist, recently stating that it is one of the relatively few annual forages for livestock in the California foothill grasslands.