Jepson eFlora: Key page
Vascular Plants of California
Key to families | Table of families and genera

Key to Aristida

View taxon page for Aristida

(For a list of species in Aristida, use the above link.)

Jepson Manual glossary definitions can be seen by moving your cursor over words underlined with dots.

1. Lower stems densely hairy ..... A. californica

1' Lower stems glabrous

2. Annual

3. Glumes 10–22 mm;   generally 10–70 mm ..... A. oligantha

3' Glumes 3–13 mm; lemma awns 3–20 mm

4. Central  straight to curved at base ..... A. adscensionis

4' Central awn spirally coiled at base ..... A. dichotoma

2' Perennial herb

5. 1° inflorescence branches  at base (upper  to  in Aristida purpurea var. wrightii)

6. Lower inflorescence branches spreading, upper ascending to appressed ..... A. purpurea var. parishii (2)

6' All inflorescence branches spreading

7. Leaf  base glabrous; lemma tip much twisted; anthers 0.8–1 mm ..... A. divaricata

7' Leaf blade base sparsely long-hairy; lemma tip slightly twisted or straight; anthers 1–2 mm ..... A. ternipes var. gentilis

5' 1° inflorescence branches appressed to ascending at base (curving or drooping in Aristida purpurea var. purpurea) ..... A. purpurea

8. Awns generally > 40 mm

9. Upper  generally 16–25 mm; lemma 0.3–0.8 mm wide just below awns, awns 0.2–0.5 mm wide at base ..... var. longiseta

9' Upper glume generally 7–16 mm; lemma 0.1–0.3 mm wide just below awns, awns 0.1–0.3 mm wide at base ..... var. purpurea (2)

8' Awns generally < 40 mm

10. 1° inflorescence branches and  stalks thread-like, curving to drooping, appearing S- or U-shaped ..... var. purpurea (2)

10' 1° inflorescence branches and spikelet stalks generally stiff, straight, generally appressed to ascending (lower spreading in Aristida purpurea var. parishii)

11. Lemma tip, awn base ± 0.1 mm wide at base, awns delicate ..... var. nealleyi

11' Lemma tip, awn base 0.2–0.3 mm wide, awns ± stiff

12. Inflorescence generally 3–15 cm;  blade generally 4–10 cm ..... var. fendleriana

12' Inflorescence generally 12–30 cm; leaf blade generally 10–25 cm

13. Inflorescence dense, ± red when young; lower branches with 10–20  ..... var. parishii (2)

13' Inflorescence ± open, tan to brown when young; lower branches with 2–10 spikelets ..... var. wrightii



Citation for the whole project: Jepson Flora Project (eds.) . Jepson eFlora, [accessed on ]

Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on .

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