| | 1. Fertile ovaries 3; fruit linear or subspheric; plant generally with 1–2 racemes |
| |
| | 2. Fruit linear, tapered to base |
| T. palustris |
| | 2' Fruit subspheric, not tapered to base |
| T. striata |
| | 1' Fertile ovaries 6; fruit oblong to ovoid; plant generally with 2 or more racemes |
| |
| | 3. Ligule entire to slightly notched, (1)1.5–5 mm; leaf blade somewhat compressed, generally 1.5–4 mm wide; plant generally > 3 dm |
| T. maritima |
| | 3' Ligule deeply 2-lobed, 0.5–1.5 mm; leaf blade ± cylindric, generally 1–1.5 mm wide; plant generally < 3(–6) dm |
| T. concinna |
| | 4. Plant generally < 3(4.5) dm; coastal salt marshes; Central Coast, South Coast |
| var. concinna |
| | 4' Plant generally > 3(6) dm; inland alkaline marshes, meadows; s High Sierra Nevada, Great Basin Floristic Province, Mojave Desert |
| var. debilis
|