Plants scapose, to 4 dm. Leaves 4-12 cm; blade nearly unlobed to shallowly 3-7-lobed distally, to 3.5 cm wide distally, copiously long-pilose. Inflorescences 1(-6)-flowered, simple, glabrous; buds long-pilose. Flowers: sepals copiously long-pilose; petals caducous, 6, white, 2.5-4 cm; filaments dilated distally; style 1-1.5 mm. Capsules persistent, oblanceoloid, 2.5-4 cm, dehiscing not more than 1/4 length. 2n = 24.
Phenology: Flowering mid spring; fruiting early summer.
Habitat: Barren, calcareous, scree slopes and weakly gypsiferous shales interbedded with marine limestones, creosote bush and blackbrush zones
Elevation: 600-1700 m
Of conservation concern.
Arctomecon merriamii is found in small populations at scattered stations from Death Valley in southeastern California to the Meadow Valley Wash of southeastern Nevada.