Calamagrostis koelerioides

Vasey
Common names: Dense-pine reedgrass
Endemic
Treatment appears in FNA Volume 24. Treatment on page 720.

Plants without sterile culms; often densely cespitose, with rhizomes 2-6 cm long, 2-4 mm thick. Culms (26) 60-85 (120) cm, unbranched, slightly scabrous; nodes 2-3 (5). Sheaths and collars usually scabrous, rarely smooth, glabrous; ligules (1.5) 2-4.5 (7) mm, truncate to obtuse, entire or sometimes lacerate; blades (2) 9-20 (30) cm long, (2) 2.5-4.5 (8) mm wide, flat, slightly scabrous, adaxial surfaces glabrous or sparsely hairy. Panicles (4) 10-13 (16) cm long, about 1 cm wide, contracted, erect to slightly nodding, often slightly interrupted towards the base, straw-colored or pale green to pale-purple; branches (1.1) 2.8-4 (6) cm, scabrous, spikelet-bearing to the base. Spikelets (4) 4.5-6 (7) mm; rachilla prolongations 1.5-2.5 (3) mm, hairs 1.5-2 mm. Glumes slightly keeled, keels smooth or slightly scabrous distally, lateral-veins visible but not prominent, apices acute; callus hairs 1.5-2 mm, 0.3-0.4 times as long as the lemmas, sparse; lemmas (3.5) 4-5 (6) mm, 0.5-1.5 mm shorter than the glumes; awns 4-5.5 mm, attached to the lower 1/10 – 1/5 of the lemmas, exserted, sometimes barely so, stout, distinguishable from the callus hairs, bent; anthers 2-3.5 mm. 2n = 28.

Distribution

Wash., Calif., Oreg., Mont., Idaho, Wyo.

Discussion

Calamagrostis koelerioides grows in mountain meadows, chaparral, and Jeffrey pine and blue spruce forests, and on talus slopes, dry hills, and ridges, occasionally on serpentine soils, at 50-2100 m. It extends from Washington south to southern California and east to Montana and western Wyoming.

Calamagrostis koelerioides is similar to C. rubescens (p. 723). The two have traditionally been distinguished by the presence of hairs on the leaf collars in C. rubescens, and their absence in C. koelerioides; a more reliable differentiation is the longer lemmas, glumes, and awns of C. koelerioides compared to C. rubescens.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

membranous +  and scarious +
hairy +  and glabrous +
0.2 cm2 mm <br />0.002 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
Kendrick L. Marr +, Richard J. Hebda +  and Craig W. Greenef +
1 (?) +  and 3 (?) +
straight +
attached +
exserted +  and lower +
distinguishable +
1/10 +  and 1/5 +
0.4 cm4 mm <br />0.004 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
9 cm90 mm <br />0.09 m <br /> (20 cm200 mm <br />0.2 m <br />) +
not evident +
flat +  and involute +
2.5mm;4.5mm +
1.1 cm11 mm <br />0.011 m <br /> (?) +
appressed;more or less drooping +
spikelike +
0.3-0.4 times as long as the lemmas +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Dense-pine reedgrass +
ascending +  and erect +
60 cm600 mm <br />0.6 m <br /> (85 cm850 mm <br />0.85 m <br />) +
not woody +
Wash. +, Calif. +, Oreg. +, Mont. +, Idaho +  and Wyo. +
1/4 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
sterile +  and bisexual +
compressed +
reduced +
subtending +
subequal +
membranous +
sparse +  and abundant +
uncinate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
not prominent +  and visible +
lanceolate +  and ovate +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
lacerate +, truncate +  and obtuse +
0.2 cm2 mm <br />0.002 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
membranous +
inconspicuous +
lanceolate +
concealed +  and prominent +
2 +  and 3 +
2 +  and 1 +
hairy +  and glabrous +
2-keeled +
pale green +  and pale-purple +
10cm +  and 13cm +
erect +  and slightly nodding +
spikelike +
1 cm10 mm <br />0.01 m <br /> (?) +
dry +  and fleshy +
1 +  and 60 +
compressed +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
1 (?) +  and 3 (?) +
simple +  and compound +
2 (?) +  and 3 (?) +
Gramineae +
Calamagrostis koelerioides +
Calamagrostis +
species +
membranous +
parallel +  and converging +
obscure +  and prominent +
plant +  and cespitose +
aquatic +  and terrestrial +