Monographs Details: Astragalus trichopodus (Nutt.) A.Gray var. trichopodus
Authors:Rupert C. Barneby
Authority: Barneby, Rupert C. 1964. Atlas of North American Astragalus. Mem. New York Bot. Gard. 13(2): 597-1188.
Synonyms:Phaca trichopoda Nutt., Tragacantha trichopoda (Nutt.) Kuntze, , , Phaca capillipes Rydb.
Description:Variety Description - Essentially like the commoner var. phoxus up to the pod; banner 11.5—15.4 mm. long; keel 9.5—11.5 mm. long; stipe of the pod 6.5-17 mm., the body turgidly and narrowly or sometimes plumply ellipsoid or half-ellipsoid, (1.3) 1.5—3.5 cm. long, (5) 6-10 (13) mm. in diameter, the sutures equally convex or the ventral one straight, the valves commonly glabrous, very rarely strigulose.

Distribution and Ecology - Shale or sandstone outcrops on ocean bluffs or low grassy hills, rare and local except in a few stations where forming colonies, known only from three restricted areas in southern California; coastal, below 300 feet, southeastern Santa Barbara and immediately adjoining Ventura Counties; south end of Catalina Island (Avalon Bay); inland, up to 1100 feet, on the Puente and Chino Hills in northeastern Orange and immediately adjacent Los Angeles and San Bernardino Counties. Map No. 112.—March to June, occasionally in fall and winter.

Discussion:Variation in length, outline, and inflation of the pod of the Santa Barbara milk-vetch, var. trichopdus, has been ably analyzed by Jepson (1936, p. 368), and the point needs no further emphasis. I can only add that one collection mentioned by Jepson, Miss Eastwood’s from Gaviota, represents the coastal phase of var. phoxus mentioned under the following variety. Maintaining Phaca capillipes as a species, Rydberg emphasized the pod’s oblique outline, but equally asymmetric pods are found in some inland stations. There is no difference in the flowers. I am inclined to question whether var. trichopodus, which grows somewhat weedily on the sea bluffs around Avalon Bay (vidi!), is truly native on Catalina. Avalon, according to the isotypus label at NY, is the type-locality of A. capillipes and the species has apparently not been collected elsewhere on the island.
Distribution:California United States of America North America|