| | 1. Leaflets lobed > 2/3 to midvein; annual or biennial; basal leaves withered at flowering; sepals green |
| S. occidentalis |
| | 1' Leaflets toothed < 1/3 to midvein; perennial herb; basal leaves present at flowering; sepals green or purplish |
| |
| | 2. Largest leaflet blade generally 5–20 mm, on stalk generally 1–4 mm, teeth generally < 15; stamens many, filaments thread-like; open areas; California Floristic Province (except High Sierra Nevada) |
| S. minor subsp. muricata |
| | 2' Largest leaflet blade 25–50 mm, on stalk 3–25 mm, teeth generally > 15; stamens 2–4, filaments not thread-like; bogs, streams; North Coast, Klamath Ranges, Outer North Coast Ranges |
| S. officinalis
|