Muhlenbergia ×curtisetosa

(Scribn.) Bush
Synonyms: Muhlenbergia schreberi var. curtisetosa Muhlenbergia curtisetosa
Treatment appears in FNA Volume 25. Treatment on page 156.

Plants perennial; occasionally rhizomatous. Culms 20-70 cm tall, less than 3 mm thick, erect, branched above; internodes smooth, shiny for most of their length, scabridulous or glabrous below the nodes. Sheaths glabrous, margins hyaline, old sheaths not flattened, papery, or spirally coiled; ligules 0.2-1.1 mm, membranous, truncate, sometimes ciliolate; blades 2-8.5 cm long, 2-5 mm wide, flat, smooth or scabridulous. Panicles 4.2-16.5 cm long, 0.2-1.5 cm wide, mostly exserted from the sheath; primary branches 0.8-7.2 cm, ascending to appressed; pedicels 0.6-3 mm, strigose. Spikelets 2.2-3.4 mm. Glumes shorter than the florets, veins scabridulous, unawned or awned, awns to 0.5 mm; lower glumes 0.4-1.5 mm, veinless (rarely 1-veined), usually truncate to rounded, occasionally acute, sometimes notched; upper glumes 0.8-1.9 mm, 1 (2) -veined, acute to acuminate; lemmas 2.2-3 (3.4) mm, lanceolate, hairy on the calluses and lower portion of the margins and midveins, hairs shorter than 1.5 mm, apices scabridulous, acuminate, awned, awns 0.5-4 mm, straight; paleas 2.2-3.1 (3.4) mm, lanceolate, intercostal region shortly pilose on the lower 1/2, apices acuminate; anthers usually not developed, occasionally 1 or 2 present, 0.3-0.9 mm, yellow. Caryopses 1.4-1.6 mm, fusiform, brown. 2n = unknown.

Distribution

Ark., Iowa, Ind., Ont., Tex., Ohio, Mo., Pa., Ill.

Discussion

Muhlenbergia ×curtisetosa grows in abandoned fields and forest openings, often near bogs, at elevations of 20-300 m. It may be a hybrid between M. schreberi (which contributes the short glumes) and either of two rhizomatous species, M. frondosa and M. tenuiflora.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

2 +  and 1 +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.09 cm0.9 mm <br />9.0e-4 m <br />) +
scabridulous +
acuminate +
Paul M. Peterson +
(Scribn.) Bush +
1 (?) +  and 3 (?) +
straight +
multiple +, , +  and single +
curled +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
not fused +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
membranous +
not pseudopetiolate +
2 cm20 mm <br />0.02 m <br /> (8.5 cm85 mm <br />0.085 m <br />) +
pubescent +  and glabrous +
scabridulous +  and smooth +
involute +, folded +  and flat +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
spikelike +
with hairs +  and glabrous +
0.14 cm1.4 mm <br />0.0014 m <br /> (0.16 cm1.6 mm <br />0.0016 m <br />) +
triangular +  and dome--shaped +
sometimes longer +
membranous +
20 cm200 mm <br />0.2 m <br /> (70 cm700 mm <br />0.7 m <br />) +
geniculate +
2 cm20 mm <br />0.02 m <br /> (300 cm3,000 mm <br />3 m <br />) +
0 cm0 mm <br />0 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
Ark. +, Iowa +, Ind. +, Ont. +, Tex. +, Ohio +, Mo. +, Pa. +  and Ill. +
not waisted +
capillary +
pistillate +  and staminate +
bisexual +  and fertile +
round +  and compressed +
reduced +
(0)1(2-3)-veined +
shorter or longer +
subtending +
uncinate +
1.5 cm15 mm <br />0.015 m <br /> (?) +
paniculate +  and racemose +
hollow +  and solid +
scabridulous +
not absent +
lanceolate +
0.22 cm2.2 mm <br />0.0022 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
acuminate +  and truncate +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.11 cm1.1 mm <br />0.0011 m <br />) +
membranous +
inconspicuous +
notched +, acute +, usually truncate +  and rounded +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
concealed +  and prominent +
2 +  and 1 +
lanceolate +
0.22 cm2.2 mm <br />0.0022 m <br /> (0.31 cm3.1 mm <br />0.0031 m <br />) +
4.2cm +  and 16.5cm +
cleistogamous +
spikelike +
0.2 cm2 mm <br />0.002 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
dry +  and fleshy +
ascending;appressed +
0.8 cm8 mm <br />0.008 m <br /> (7.2 cm72 mm <br />0.072 m <br />) +
spikelike +
not flattened +
1 +  and 60 +
compressed +
0.22 cm2.2 mm <br />0.0022 m <br /> (0.34 cm3.4 mm <br />0.0034 m <br />) +
1 +  and 3 +
compound +  and simple +
2 (?) +  and 3 (?) +
Muhlenbergia schreberi var. curtisetosa +  and Muhlenbergia curtisetosa +
Muhlenbergia ×curtisetosa +
Muhlenbergia +
species +
membranous +
shorter than to longer than the florets +
acute +  and acuminate +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.19 cm1.9 mm <br />0.0019 m <br />) +
7 (?) +  and 13 (?) +
scabridulous +
aquatic +  and terrestrial +
dioecious +, monoecious +  and synoecious +