Stanleya viridiflora Nuttall var. confertiflora B. L. Robinson in A. Gray et al., Syn. Fl. N. Amer. 1(1,1): 178. 1895; S. annua M. E. Jones; S. rara A. Nelson

Annuals or biennials; (glaucous), glabrous throughout. Stems erect, unbranched, (slightly ribbed), 2-6(-8) dm. Basal leaves (often withered by flowering); blade obovate to ovate, margins entire. Cauline leaves sessile; blade (fleshy), lanceolate, (2.2-)4-13(-16) cm × (5-)10-30(-40) mm, (smaller distally, base auriculate to sagittate), margins entire. Racemes dense, (slightly or not elongated in fruit). Fruiting pedicels horizontal to divaricate-ascending, 10-20(-26) mm. Flowers: sepals oblong-linear, 6-12 mm; petals yellow becoming whitish, narrowly linear to filiform, (12-)14-25 × 0.5-1.5 mm, (margins crisp), claw (nearly linear), 5-11 mm, slightly wider at base; filaments 12-17 mm; anthers 3-4.5 mm; gynophore (6-)10-18 mm. Fruits suberect to divaricate-ascending, slightly curved inward, (torulose), subterete, 2-5.2(-6) cm × 1.5-2.2 mm; ovules 40-62 per ovary; style 0.6-1.7 mm. Seeds oblong, 1.5-2.5 × 0.8-1 mm.

Flowering Apr-Jun. Barren clay slopes in sagebrush communities, heavy clay flats, loose soil mounds, dry sandy grounds, alkaline meadows and flats; of conservation concern; 600-1500 m; Idaho, Oreg.

Stanleya confertiflora is distributed in Gooding, Owyhee, and Washington counties in Idaho, and in Baker, Harney, and Malheur counties in Oregon.