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.

Perennial, Herbs, Stems woody below, or from woody crown or caudex, Taproot present, Nodules present, Stems or branches arching, spreading or decumbent, Stems less than 1 m tall, Stems solid, Stems or young twigs sparsely to densely hairy, Stem hairs hispid to villous, Leaves alternate, Leaves petiolate, Stipules conspicuous, Stipules membranous or chartaceous, Stipules persistent, Stipules free, Stipules connate to each other, forming a tuber or sheath, Leaves compound, Leaves odd pinnate, Leaf or leaflet margins entire, Leaflets opposite, Leaflets 5-9, Leaflets 10-many, Leaves hairy on one or both surfaces, Flowers in axillary clusters or few-floweredracemes, 2-6 flowers, Inflorescences racemes, Inflorescence axillar y, Bracts very small, absent or caducous, Flowers zygomorphic, Calyx 5-lobed, Calyx glabrous, Petals separate, Corolla papilionaceous, Petals clawed, Petals ochroleucous, cream colored, Petals blue, lavander to purple, or violet, Banner petal narrow or oblanceolate, Wing petals narrow, oblanceolate to oblong, Wing tips obtuse or rounded, Keel petals auriculate, spurred, or gibbous, Keel tips obtuse or rounded, not beaked, Stamens 9-10, Stamens diadelphous, 9 united, 1 free, Filaments glabrous, Style terete, Style persistent in fruit, Fruit a legume, Fruit unilocular, Fruit humistrate, lying on the ground, Fruit freely dehiscent, Fruit oblong or ellipsoidal, Fruit exserted from calyx, Fruit inflated or turgid, Fruit beaked, Fruit hairy, Fruit 3-10 seeded, Fruit 11-many seeded, Seeds cordiform, mit-shaped, notched at one end, Seed surface smooth, Seeds olive, brown, or black.

Astragalus pulsiferae is a species of milkvetch known by the common name Ames's milkvetch. It is native to California and Nevada, and it is known but rare in Washington. It is known from many habitat types, including mountains and plateaus.