Naked Milkvetch

Brachyphragma serenoi (Kuntze) Rydb. Am. Jour. Bot 16: 205. 1929.
Astragalus nudus S. Wats. Bot. King's Expl. 74. 1871. Not .4. nudus Clos. 1846. Tragacantha Serenoi Kuntze, Rev. Gen. 941. 1891. Astragalus obtains Sheldon, Minn. Bot. Stud. 1: 19. 1894. Astragalus Serenoi Sheldon, Minn. Bot. Stud. 1: 130. 1894. Astragalus canonis M. E. Jones, Contr. W. Bot. 8: 15. 1898.
A perennial, growing in clumps; stems tall, 4-7 dm. high, glabrous, striate, branched below; leaves 1-1.5 dm. long, spreading; stipules 2-5 mm. long, deltoid, the upper green, reflexed, the lower ones scarious; leaflets 3-7, those of the upper leaves linear or narrowly oblong, acute at each end, 2-3 cm. long, 1-4 mm. wide, sparingly strigose but soon glabrate above, permanently silvery-strigose beneath, those of the lower leaves oval, 12-15 mm. long; peduncles 1-2 dm. long, erect; racemes often 1 dm. long, lax; bracts subulate, 2 mm. long; pedicels about 1 mm. long; calyx black-strigose, tapering at the base, the tube 7 mm. long, 3 mm. wide, the teeth subulate, 3 mm. long; corolla purple with a white base, with darker veins; banner about 20 mm. long, obovate, moderately arched, notched at the apex; wings 18 mm. long, the blade oblong-falcate, with a large reflexed auricle; keel-petals slightly shorter, the blade lunate, rounded at the apex; pods woody, oblong, about 3 cm. long, 1 cm. thick, abruptly acuminate at each end, subterete, the septum 3-4 mm. wide, disappearing in the upper one-fourth of the pod.
Type locality: West Humboldt Mountains, Nevada. Distribution: Nevada and eastern California.

Perennial, Shrubs, Herbs, Stems woody below, or from woody crown or caudex, Taproot present, Nodules present, Stems erect or ascending, Stems less than 1 m tall, Stems solid, Stems or young twigs sparsely to densely hairy, Leaves alternate, Leaves petiolate, Stipules conspicuous, Stipules membranous or chartaceous, Stipules persistent, Stipules free, 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, Inflorescences race mes, Inflorescence axillary, Bracts very small, absent or caducous, Flowers zygomorphic, Calyx 5-lobed, Calyx hairy, Petals separate, Corolla papilionaceous, Petals clawed, Petals blue, lavander to purple, or violet, Petals bicolored or with red, purple or yellow streaks or spots, 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 freely dehiscent, Fruit oblong or ellipsoidal, Fruit rugose wrinkled or reticulate, Fruit or valves persistent on stem, Fruit fleshy, Fruit coriaceous or becoming woody, Fruit exserted from calyx, Fruit beaked, Fruit glabrous or glabrate, Fruit 11-many seeded, Seeds cordiform, mit-shaped, notched at one end, Seed surface smooth, Seeds olive, brown, or black.