Plant Database

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Plant Characteristics

Duration: Perennial
Habit: Shrub
Leaf Arrangement: Alternate
Fruit Type: Legume
Size Notes: "4-9 (15) dm tall." (bibref: 1812).
Leaf: "Leaf-spurs up to 0.6 mm long; stipules triangular, 0.2-0.9 mm long, deciduous, charged at apex and often on margins with 1-3 glands; leaves short-petioled, (1) 1.4-3 cm long, with narrowly margined, punctate rachis and 3-8 (9) pairs of obovate to linear-oblanceolate, obtuse to emarginate, flat or loosely folded, thick-textured leaflets 2-7 mm long." (bibref: 1812).
Flower: "Peduncles terminal to branchlets, 0.5-1.5 cm long; racemes loose and open, the flowers spreading at full anthesis, the glabrous or puberulent axis becoming (1) 2-9 cm long; bracts early deciduous, ovate-elliptic, submembranous, 0.6-1.5 mm long, gland-tipped; pedicels spreading-ascending, 0.7-1.4 mm long, charged near apex with a pair of orange glands; calyx 3.7-5 mm long, either pilosulous throughout with spreading hairs up to 0.3-0.5 mm long or glabrous up to the margins of the ciliolate, internally silky-pubescent calyx-teeth, the tube 2.4-3.3 mm long (measured to lateral sinus), the dorsal sinus shallower than the rest and the orifice hence oblique, the ribs prominent but not cordlike, the firm, pleated intervals charged above middle with 1-4 large red-orange glands, the teeth ovate to oblong-ovate, obtuse to subacute, gland-mucronulate, herbaceous, obscurely 3-nerved below apex, very unequal, the ventral pair nearly twice as broad and longer than the rest, 1.1-2.3 mm long; petals bright pink- or violet-purple marcescent, glabrous, all glandless or the banner sometimes charged on back with a subapical gland; banner (5.5) 6-8.4 mm long, the claw (1.8) 2.2-2.5 mm, the ovate, basally broadly cuneate or cordate, sometimes suborbicular-cordate, notched blade (4.4) 4.8-6.2 mm long, (4.2) 4.8-6 mm wide; wings 7.6-8.6 mm long, the claw 2-2.7 mm, the oblong obtuse blade 5.8-6.6 mm long, 2.6-3.2 mm wide; keel (only a trifle longer than wings) 7.4-9 mm long, the claws (1.9) 2.1-3.2 mm, the broadly obovate blades 5.6-6.7 mm long, 3.4-3.8 mm wide; androecium 10-merous, 6-7.7 mm long, the longer filaments free for 2.5-3.5 mm, the connective gland-tipped, the anthers 0.8-0.9 mm long." (bibref: 1812).
Fruit: "Pod 4-4.5 mm long, compressed, membranous and glabrous at base, thence firm, rugulose, pilosulous, gross-glandular; ovules 2 (3); seed 1, 2.1-2.6 mm long." (bibref: 1812).

Bloom Information

Bloom Color: Pink , Purple , Violet
Bloom Time: May , Jun , Jul , Aug
Bloom Notes: "Petals bright pink- or violet-purple marcescent." (bibref: 1812).

Distribution

USA: AZ , CO , UT
Native Distribution: "Central Wayne, eastern Garfield, and adjoining San Juan counties, Utah (P. t. var. thompsoniae); southeastern San Juan County, Utah, and Coconino County, Arizona (P. t. var. whitingii)." (bibref: 1812).
Native Habitat: As given for the varieties. (bibref: 1812).

Additional resources

USDA: Find Psorothamnus thompsoniae in USDA Plants
FNA: Find Psorothamnus thompsoniae in the Flora of North America (if available)
Google: Search Google for Psorothamnus thompsoniae