Directory       News       Site Map       Home
         
    Jepson eFlora
Key to families | Table of families and genera

Specimen numbers are hyperlinked to records in the Consortium of California Herbaria data view where possible. Taxa are hyperlinked to entries in the Jepson Interchange via the "[Online Interchange]" link.

 

CALAMAGROSTIS REED GRASS

Paul M. Peterson, Jeffery M. Saarela & Craig W. Greene


Perennial herb, generally from rhizomes. Stem: 1–15 dm, generally not branched, ± smooth; nodes (1)2–8. Leaf: generally basal and cauline; sheath smooth or scabrous; ligule membranous; blade flat to inrolled. Inflorescence: panicle-like, open to dense; branches ± drooping to appressed; spikelets ascending to appressed. Spikelet: glumes subequal, generally lanceolate, acute to acuminate, lower generally 1-veined, upper 3-veined; floret 1, breaking above glumes; axis prolonged beyond floret, hairy; callus hairy; lemma < glumes, awned from below middle to near base, tip generally 4-toothed, veins 3–5, awn straight to twisted, bent; palea ± = lemma, thin.
± 265 species (including Deyeuxia): cool temperate (especially moist montane); some forage value. (Greek: reed grass) [Marr et al. 2007 FNANM 24:706–732] Hybridization, polyploidy (diploids unknown), and asexual seed set contribute to taxonomic difficulty.
Unabridged references: [Greene 1980 Ph.D. Dissertation Harvard Univ]

Key to Calamagrostis

1. Awn exserted 1–10 mm beyond glume tips, twisted and bent

2. Panicle open, branches spreading to ascending

3. Plant from rhizomes; stem 5–15 dm; leaf blade generally cauline, 3–10 mm wide, flat; coastal, < 500 m ..... C. bolanderi

3' Plant cespitose, rhizomes 0; stem generally 1.2–5.4 dm; leaf blade generally basal, 0.2–1.7 mm wide, inrolled to flat; > 1500 m

4. Leaf blade 7–11-veined, tip prow-shaped; inflorescence (4)5.7–8.5 cm; callus hairs 0.3–1.2 mm ..... C. breweri (2)

4' Leaf blade 3–5-veined, tip straight-sided; inflorescence 1.9–5.7(7.5) cm; callus hairs 0.3–0.6 mm ..... C. muiriana (2)

2' Panicle dense, narrow, branches ascending to appressed

5. Awn 12–15(17) mm, exserted 4–10 mm beyond the glume tips; glumes 8–10 mm ..... C. foliosa

5' Awn (4.6)5–7.5(9) mm, exserted 1–3 mm beyond the glume tips; glumes 4.5–8 mm

6. Leaf blade with small white-opaque hooks between the veins visible only with magnification, upper surface scabrous; generally on serpentine soils, < 1065 m ..... C. ophitidis (2)

6' Leaf blade without small white-opaque hooks between the veins, upper surface soft-hairy; generally on rocky slopes, sandy soils, 1300–4000 m ..... C. purpurascens (2)

1' Awn included or occasionally prolonged < 1 mm beyond glume tips, straight or twisted and bent

7. Leaf blade 0.2–1.7 mm wide; panicle 1.9–8.5 cm; callus hairs sparse

8. Leaf blade 7–11-veined, tip prow-shaped; panicle (4)5.7–8.5 cm; callus hairs 0.3–1.2 mm ..... C. breweri (2)

8' Leaf blade 3–5-veined, tip straight-sided; panicle 1.9–5.7(7.5) cm; callus hairs 0.3–0.6 mm ..... C. muiriana (2)

7' Leaf blade (1.5)2–10(20) mm wide; panicle 4–30 cm; callus hairs abundant or sparse

9. Panicle ± open, lower branches spreading to ascending

10. Leaf collar generally puberulent or hairy-tufted; callus hairs < 2 mm ..... C. rubescens (2)

10' Leaf collar smooth or scabrous, rarely hairy; callus hairs (1.5)2–3.5(4.5) mm

11. Glumes 5–7(7.5) mm; stems generally unbranched below with 1–2(3) nodes per stem; ligules 1–4 mm, entire, truncate, generally hidden by expanded collar below ..... C. nutkaensis

11' Glumes 3–4.5 mm; stems generally branched below with (2)3–8 nodes per stem; ligules 3–8 mm, irregularly cut, obtuse to acute, not hidden by expanded collar below ..... C. canadensis

12. Glumes smooth or scabrous, projections along keel straight, tips acute (acuminate); spikelets 2.5–3.5(4) mm ..... var. canadensis

12' Glumes scabrous across entire surface, rarely smooth, projections along keel often bent, tips acuminate; spikelets (3.5)4–4.5(5.2) mm ..... var. langsdorffii

9' Panicle ± dense, narrow, lower branches appressed (occasionally ascending in C. rubescens, C. stricta)

13. Glumes generally < than 3 × longer than wide ..... C. stricta

14. Glumes 3–6 mm, generally thick, margin opaque; callus hairs 2–4.5 mm; spikelet axis 1–1.5 mm; longest panicle branches 1.5–9.5 cm ..... subsp. inexpansa

14' Glumes 2–3(3.5) mm, generally thin, margin ± translucent; callus hairs 1–3 mm; spikelet axis 0.5–1 mm; longest panicle branches 1.5–4 cm ..... subsp. stricta

13' Glumes generally > 3 × longer than wide

15. Leaf blade with small white-opaque hooks between the veins visible only with magnification ..... C. ophitidis (2)

15' Leaf blade without small white-opaque hooks between the veins

16. Leaf blade generally soft-hairy on the upper surface ..... C. purpurascens (2)

16' Leaf blade smooth or scabrous but not soft-hairy on the upper surface

17. Awn 4–5.5 mm; leaf collar scabrous or smooth; rhizomes 2–6 cm, 2–4 mm thick, stout ..... C. koelerioides

17' Awn 2–4 mm; leaf collar generally puberulent or hairy-tufted; rhizomes 10–20 cm, 1.5–2 mm thick, slender ..... C. rubescens (2)

Contact/Feedback

Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html [accessed on month, day, year]
Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on [month, day, year].
We encourage links to these pages, but the content may not be downloaded for reposting, repackaging, redistributing, or sale in any form, without written permission from The Jepson Herbarium.