Shrubs , to 4 m. Lateral bud exposed. Petiole 5-10 mm, pubescent to glabrous. Leaf blade ovate-lanceolate to oblong-lanceolate or ovate-elliptic, 5-15 × 2-8 cm, base rounded to nearly cordate, apex acute to obtuse; surfaces abaxially green, pubescent to glabrous. Flowers : hypanthium campanulate or ovoid-campanulate at maturity, 2-4 × 1-2 cm; tepals linear to linear-spatulate or ovate-elliptic, 2-6 × 0.5-1 cm, apex rounded; stamens 10-15, linear to oblong-linear. 2 n = 22.

Flowering late spring-early fall, fruiting mid fall. Along streams and on moist canyon slopes; 200-1600 m; Calif., Wash.

Calycanthus occidentalis grows in the northern Coast Range, the southern Cascades Range, and the western Sierra Nevada. It is ecologically similar to C . f loridus ; it consistently differs from that taxon in a number of vegetative and floral characteristics. Because of an apparent lack of hardiness, C . occidentalis is cultivated less often than C . floridus .

Some American Indians used scraped bark of Calycanthus occidentalis medicinally in treating severe colds (D. E. Moerman 1986).