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dense-pine reed grass, fire reedgrass

one-and-a-half-flower reedgrass

Habit Plants without sterile culms; often densely cespitose, with rhizomes 2-6 cm long, 2-4 mm thick. Plants rarely with sterile culms; strongly cespitose, usually without rhizomes, sometimes with rhizomes 1-2 cm long, 1-2 mm thick.
Culms

(26)60-85(120) cm, unbranched, slightly scabrous;

nodes 2-3(5).

(15)30-46(50) cm, unbranched, usually smooth, rarely slightly scabrous beneath the panicles;

nodes 1-2(3).

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.

and collars smooth;

ligules (0.5)2-5(6) mm, usually truncate, sometimes obtuse, usually entire, sometimes lacerate;

blades (3)8-25(31) cm long, (2)3-7 mm wide, flat, abaxial surfaces usually scabrous, rarely smooth, adaxial surfaces smooth or slightly scabrous, 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.

4-11(12) cm long, 0.8-2.5(2.8) cm wide, erect, contracted to somewhat open, usually purple-tinged, sometimes brown or green;

branches 1.5-3(4) cm, scabrous, prickles sometimes almost hairlike, usually spikelet-bearing to the base, lowest branches sometimes not so.

Spikelets

(4)4.5-6(7) mm;

rachilla prolongations 1.5-2.5(3) mm, hairs 1.5-2 mm.

(5)5.5-8.5(9.5) mm;

rachilla prolongations (1)1.5(2.2) mm, hairs 1-2.2 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.

keeled, keels usually scabrous for their whole length, sometimes the surfaces also scabrous, lateral veins prominent, apices long-acuminate, usually twisted distally;

callus hairs (0.8)1.2-1.8(3) mm, 0.1-0.4 times as long as the lemmas, abundant;

lemmas (3.5)4-4.5(6) mm, (0.5)1-2.5(4.5) mm shorter than the glumes;

awns (5.4)7-11(13) mm, attached to the lower 1/10 – 2/5 of the lemmas, exserted more than 2 mm, stout, easily distinguished from the callus hairs, bent;

anthers (1.2)2.2-3(3.4) mm.

2n

= 28.

= 28.

Calamagrostis koelerioides

Calamagrostis sesquiflora

Distribution
from FNA
CA; ID; MT; OR; WA; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
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.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Calamagrostis sesquiflora grows at 0-1000 m in open heath, meadows, and forest openings, on or at the base of open rocky cliffs and knolls, as well as in moist talus. It grows in strictly maritime habitats along the west coast of North America, from the Aleutian Islands in Alaska to the Queen Charlotte Islands and south to Vancouver Island (Brooks Peninsula) in British Columbia. There is also a single collection from the coast of mainland British Columbia. In northeast Asia, it ranges into the Kamchatka Peninsula and Kuril Archipelago.

Some specimens from the northwestern United States are incorrectly identified, partly because an earlier name for Trisetum spicatum (L.) K. Richt. was Trisetum sesquiflorum Trin.

Calamagrostis sesquiflora has sometimes included C. tacomensis (see next) [as C. vaseyi Beal]. Several specimens that were previously identified as C. sesquiflora are actually C. tacomensis. Calamagrostis sesquiflora differs in preferring moister habitats, having wider leaves, callus hairs that are shorter relative to the lemmas, shorter panicle branches, and glumes that are often twisted at the apices.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 24, p. 720. FNA vol. 24, p. 714.
Parent taxa Poaceae > subfam. Pooideae > tribe Poeae > Calamagrostis Poaceae > subfam. Pooideae > tribe Poeae > Calamagrostis
Sibling taxa
C. bolanderi, C. breweri, C. cainii, C. canadensis, C. cinnoides, C. deschampsioides, C. epigejos, C. foliosa, C. howellii, C. lapponica, C. montanensis, C. muiriana, C. nutkaensis, C. ophitidis, C. perplexa, C. pickeringii, C. porteri, C. purpurascens, C. rubescens, C. scopulorum, C. sesquiflora, C. stricta, C. tacomensis, C. tweedyi, C. ×acutiflora
C. bolanderi, C. breweri, C. cainii, C. canadensis, C. cinnoides, C. deschampsioides, C. epigejos, C. foliosa, C. howellii, C. koelerioides, C. lapponica, C. montanensis, C. muiriana, C. nutkaensis, C. ophitidis, C. perplexa, C. pickeringii, C. porteri, C. purpurascens, C. rubescens, C. scopulorum, C. stricta, C. tacomensis, C. tweedyi, C. ×acutiflora
Synonyms C. purpurascens subsp. tasuensis, C. purpurascens subsp. arctica, C. arctica
Name authority Vasey (Trin.) Tzvelev
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