Native to (or naturalized in) Oregon:
- Broadleaf, deciduous, multistemmed, spiny shrub, growing upright to a about 4 ft (1.2 m) tall, 1-3 spines ("thorns") per each branch node. Leaves alternate, simple, up to 2.5 cm long, hairless to hairy or woolly, divided into 3 or 5 rounded, toothed lobes. Flowers are solitary or 2-3 per cluster, they hang pendent from the branches and each has 5 reflexed red-purple sepals around a tube-shaped ring of smaller white or pinkish petals, from which the stamens and stigmas protrude. Fruit is 2.5 cm long and covered in thick, long spines; red or purple when mature.
- Hardy to USDA Zone 7 Except for extreme southwest Oregon, essentially limited to the mountains over the entire length of California. Three varieties are recognized: R. r. var. amictum, R. r. var. cruentum, and R. r. var. roezlii.