The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

mat muhly, Matted muhly, muhlenbergie de Richardson, Richardson's muhly, soft-leaf muhly

cutover muhly, savannah hairgrass

Habit Plants perennial; rhizomatous, not cespitose, often mat-forming. Plants perennial; cespitose, not rhizomatous.
Culms

5-30 cm tall, 0.4-1 mm thick, decumbent, geniculate, or erect;

internodes usually nodulose (occasionally smooth) for most of their length, puberulent or nodulose below the nodes.

60-100 (150) cm, erect from the base, not conspicuously branched;

internodes mostly glabrous, sometimes puberulent below the nodes.

Sheaths

shorter or longer than the internodes, glabrous;

ligules 0.8-3 mm, membranous, acute to truncate, erose;

blades 0.4-6.5 cm long, 0.5-4.2 mm wide, flat or involute, straight or arcuate-spreading, glabrous abaxially, hirtellous adaxially.

glabrous or puberulent, rounded basally, becoming fibrous, not flat or spirally coiled, at maturity;

ligules 1.8-5(10) mm, membranous, firm, strongly decurrent, obtuse;

blades 20-50(80) cm long, 2-4 mm wide, flat or involute, smooth abaxially, scabrous adaxially.

Panicles

1-15 cm long, 0.1-1.7 cm wide, exserted, narrow or spikelike, rachises usually concealed by the branches;

primary branches 0.4-5 cm, usually closely appressed at maturity, rarely diverging up to 20° from the rachises;

pedicels 0.2-2 mm, setulose.

15-50(60) cm long, 5-30 cm wide, longer than wide, diffuse;

primary branches 2-20 cm, capillary, spreading 30-100° from the rachises, naked basally, lower branches with 5-20 spikelets;

pedicels 4-50 mm, longer than the spikelets, capillary, flexible, widely divergent at maturity.

Spikelets

1.7-3.1 mm, occasionally with 2 florets.

3-5 mm, often purplish, sometimes brownish or bronze.

Glumes

subequal, 0.6-2 mm, 1/3– 1/2 as long as the lemmas, green, 1(2)-veined, acute, sometimes mucronate, mucros less than 0.2 mm;

lemmas 1.7-2.6(3.1) mm, lanceolate, dark greenish, plumbeous, or mottled, glabrous, apices scabridulous, acute to acuminate, sometimes mucronate, mucros to 0.5 mm;

paleas 1.2-2.4(2.9) mm, lanceolate, acute;

anthers 0.9-1.6 mm, yellow to purplish.

subequal, 1.5-3.3 mm, shorter than the florets, glabrous;

lower glumes 1-veined, unawned;

upper glumes usually 1-veined, rarely 3-veined, acute to acuminate, often erose, sometimes mucronate;

lemmas 3-5 mm, lanceolate, calluses shortly pubescent, apices acuminate, without setaceous teeth, usually unawned, if, as rarely, awned, awns 1-3 mm, clearly demarcated from the lemma bodies;

paleas 2-4.5 mm, lanceolate, acuminate, unawned;

anthers 1.5-2 mm, purple.

Caryopses

0.9-1.6 mm, narrowly ellipsoid, brown.

2-2.5 mm, narrowly elliptic, brownish.

2n

= 40.

= unknown.

Muhlenbergia richardsonis

Muhlenbergia expansa

Distribution
from FNA
AK; AZ; CA; CO; ID; ME; MI; MN; MT; ND; NE; NM; NV; OR; SD; UT; WA; WI; WY; AB; BC; MB; NB; NT; ON; QC; SK; YT
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; FL; GA; KY; LA; MS; NC; SC; TX; VA
[WildflowerSearch map]
[BONAP county map]
Discussion

Muhlenbergia richardsonis grows in open sites in alkaline meadows, prairies, sandy arroyo bottoms, talus slopes, rocky flats and the shores of rivers, at elevations of 60-3300 m. It is the most widespread species of Muhlenbergia in the Flora region, extending from the Yukon Territory to Quebec in the north and to northern Baja California, Mexico, in the south. Morden and Hatch (1996) reported that it also grows in Alaska, but no voucher specimen has been located.

Muhlenbergia richardsonis is often confused with M. cuspidata, which differs in lacking rhizomes and having shorter ligules, and sometimes with M. filiformis, which differs in being a weak annual with glabrous internodes and obtuse, erose glumes.

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

Muhlenbergia expansa grows in perennially moist to wet soils in pitcher plant bogs, pine savannahs, and flat-woods, usually in sandy soils and at elevations of 0-300 m. Its primary range is the coastal plain of the south-eastern United States.

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

Source FNA vol. 25, p. 177. FNA vol. 25, p. 188.
Parent taxa Poaceae > subfam. Chloridoideae > tribe Cynodonteae > Muhlenbergia Poaceae > subfam. Chloridoideae > tribe Cynodonteae > Muhlenbergia
Sibling taxa
M. andina, M. appressa, M. arenacea, M. arenicola, M. arizonica, M. arsenei, M. asperifolia, M. brevis, M. bushii, M. californica, M. capillaris, M. crispiseta, M. curtifolia, M. cuspidata, M. depauperata, M. diversiglumis, M. dubia, M. dumosa, M. elongata, M. eludens, M. emersleyi, M. expansa, M. filiculmis, M. filiformis, M. fragilis, M. frondosa, M. glabrifloris, M. glauca, M. glomerata, M. jonesii, M. lindheimeri, M. longiligula, M. mexicana, M. microsperma, M. minutissima, M. montana, M. palmeri, M. pauciflora, M. pectinata, M. peruviana, M. polycaulis, M. porteri, M. pungens, M. racemosa, M. ramulosa, M. repens, M. reverchonii, M. rigens, M. rigida, M. schreberi, M. sericea, M. setifolia, M. sinuosa, M. sobolifera, M. spiciformis, M. straminea, M. sylvatica, M. tenuiflora, M. tenuifolia, M. texana, M. thurberi, M. torreyana, M. torreyi, M. uniflora, M. utilis, M. villiflora, M. wrightii, M. ×curtisetosa, M. ×involuta
M. andina, M. appressa, M. arenacea, M. arenicola, M. arizonica, M. arsenei, M. asperifolia, M. brevis, M. bushii, M. californica, M. capillaris, M. crispiseta, M. curtifolia, M. cuspidata, M. depauperata, M. diversiglumis, M. dubia, M. dumosa, M. elongata, M. eludens, M. emersleyi, M. filiculmis, M. filiformis, M. fragilis, M. frondosa, M. glabrifloris, M. glauca, M. glomerata, M. jonesii, M. lindheimeri, M. longiligula, M. mexicana, M. microsperma, M. minutissima, M. montana, M. palmeri, M. pauciflora, M. pectinata, M. peruviana, M. polycaulis, M. porteri, M. pungens, M. racemosa, M. ramulosa, M. repens, M. reverchonii, M. richardsonis, M. rigens, M. rigida, M. schreberi, M. sericea, M. setifolia, M. sinuosa, M. sobolifera, M. spiciformis, M. straminea, M. sylvatica, M. tenuiflora, M. tenuifolia, M. texana, M. thurberi, M. torreyana, M. torreyi, M. uniflora, M. utilis, M. villiflora, M. wrightii, M. ×curtisetosa, M. ×involuta
Synonyms Sporobolus depauperatus, M. squarrosa M. capillaris var. trichopodes
Name authority (Trin.) Rydb. (Poir.) Trin.
Web links