Ames' Milkvetch

Phaca pulsiferae (A. Gray) Rydberg
Astragalus Pulsiferae [" Pulsiferi"] A. Grav, Proc. Am. Acad. 10: 69. 1874. Tragacantha Puis, ferae Kuntze, Rev. Gen. 947. 1891.
Perennial, with a thick woody root and cespitose caudex; stems rather slender, villous, branched, 1-2 dm. long; leaves 2-4 cm. long, the rachis villous; stipules broadly deltoid, acuminate, distinct, 2 mm. long; leaflets 5-11, obovate-cuneate, often emarginate, 5-10 mm. long, villous; peduncles 1-2 cm. long; racemes 3-5 flowered; calyx villous, the tube 1.5-2 mm. long, the lobes subulate, 2 mm. long; corolla white, purple-tinged, 6 mm. long; banner obovate, emarginate; wings much shorter, the blade oblanceolate ; keel-petals short and broad, strongly incurved, the apex purple and obtuse; pod sessile, long-villous, 1.5 cm. long, obliquely ovoid, strongly arched, gibbous on the lower suture, the upper straight or slightly upcurved.
Type locality: Sierra and Plumas counties. California. Distribution: Northern Sierra Nevada, California.