Distribution: Chiefly east of the Cascades in Washington; British Columbia south to California, east to Montana and Colorado.
Habitat: Dry, often rocky or gravelly soil, desert valleys to lower mountains.
Flowers: July-September
Origin: Native
Growth Duration: Biennial, Perennial
Conservation Status: Not of concern
Biennial or short-lived perennial from a deep taproot, the stem 3-10 dm. tall, single and branched, but often appearing multi-stemmed when branched near the base; harshly scabrid-pubescent.
Leaves alternate, the lower ones oblanceolate, with slender petioles, deeply pinnatifid, the lobes often angled backward, up to 15 cm. long; upper leaves sessile, oblong to ovate-oblong, more shallowly lobed.
Flowers solitary and terminal on branch ends and often in the upper leaf axils, each subtended by 1-several entire or few-toothed bracts; calyx lobes 5, linear, 1.5 -4 cm. long; petals 5, lemon yellow, 2.5-8 cm. long, narrowly oblong or oblong-lanceolate; stamens very numerous, 2/3 the length of the petals, the 5 outer ones without anthers, much widened and petaloid, alternate with the petals; style 1, stigma 3-4 mm., ovary inferior, 1-celled.
Capsule 1.5-3.5 cm. long.
PNW Herbaria: Specimen records of Mentzelia laevicaulis in the Consortium of Pacific Northwest Herbaria database.
WA Flora Checklist: Mentzelia laevicaulis checklist entry.
OregonFlora: Mentzelia laevicaulis information.
E-Flora BC: Mentzelia laevicaulis atlas page.
CalPhotos: Mentzelia laevicaulis photos.
USDA Plants: Mentzelia laevicaulis information.