Native to (or naturalized in) Oregon:
- Broadleaf deciduous tree, 15-40 ft (4.5-12 m), often greater width; stems have purple spines (thorns), ~1 cm long. Leaves alternate, simple, deeply, 4-7 lobed, 2.5-5 cm long, slightly pubescent on both surfaces. Flowers white, 1.5-2 cm wide, 20 anthers, 2, occasionally 1 or 3, purple styles. Fruit 1.5 cm long, at first bright red, then dark red or purple-black with light dots, fleshy, usually with 2 seeds (nutlets).
- Hardy to USDA Zone 5 Native to southern Russia.
- ambigua: uncertain, doubtful (an apparent reference to its very close similarity to the more common C. monogyna which generally has 1 seed per fruit).