Eriochloa contracta

Hitchc.
Common names: Prairie cupgrass
Endemic
Treatment appears in FNA Volume 25. Treatment on page 509.

Plants annual; cespitose. Culms 20-100 cm, erect or decumbent, sometimes rooting at the lower nodes; internodes pilose or pubescent; nodes pubescent to puberulent. Sheaths sparsely to densely pubescent; ligules 0.4-1.1 mm; blades 6-12 (22) cm long, 2-8 mm wide, linear, flat to conduplicate, straight, appressed to divergent, both surfaces sparsely to densely pubescent with short, evenly spaced hairs. Panicles 6-20 cm long, 0.3-1.2 cm wide; rachises pilose, longer hairs 0.1-0.8 mm; branches 10-20 (28), 15-45 (60) mm long, 0.2-0.4 mm wide, appressed, pubescent to setose, not winged, with 8-16 mostly solitary spikelets, occasionally paired at the base of the branches; pedicels 0.2-1 mm, variously hirsute below, apices with fewer than 10 hairs more than 0.5 mm long. Spikelets (3.1) 3.5-4.5 (5) mm long, 1.2-1.7 mm wide, lanceolate. Upper glumes as long as the lower lemmas, with sparsely appressed pubescence on the lower 2/3, scabrous or glabrous distally, 3-9-veined, acuminate and awned, awns 0.4-1 mm; lower florets sterile; lower lemmas 3-4.3 mm long, 1.2-1.7 mm wide, lanceolate, setose, 3-7-veined, acuminate, unawned or mucronate; lower paleas absent; upper lemmas 2-2.5 mm, indurate, elliptic, 5-7-veined, acute to rounded and awned, awns 0.4-1.1 mm; upper paleas indurate, faintly rugose, blunt. 2n = 36.

Distribution

D.C., Fla., N.Mex., Tex., La., Ala., Ind., Tenn., Nev., Va., Colo., Calif., Ark., Ill., Ariz., Ont., Ohio, Utah, Mo., Kans., Minn., Nebr., Okla., Miss., S.C., Ky.

Discussion

Eriochloa contracta grows in fields, ditches, and other disturbed areas. It is known only from the United States, being native and common in the central United States, and adventive to the east and southwest. It differs from E. acuminata in its tightly contracted, almost cylindrical panicles and longer lemma awns, but intermediate forms can be found. It can also be confused with first-year plants of the perennial E. punctata, which have glabrous leaves, narrower and more tapering spikelets, and longer lemma awns.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number."elongated" is not a number.

... more about "Eriochloa contracta"
anatomy +  and kranz +
Robert B. Shaw +, Robert D. Webster +  and Christine M. Bern +
Hitchc. +
1 (?) +  and 3 (?) +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.11 cm1.1 mm <br />0.0011 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
divergent +  and parallel +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
membranous +
disarticulating +  and pseudopetiolate +
non-radiate +  and radiate +
straight +
6 cm60 mm <br />0.06 m <br /> (12 cm120 mm <br />0.12 m <br />) +
usually linear +  and lanceolate occasionally ovate +
2mm;8mm +
15mm +  and 45mm +
pubescent +  and setose +
spikelike +
0.2mm;0.4mm +
not developed +
terete +  and compressed +
sometimes longer +
Prairie cupgrass +
decumbent +  and erect +
20 cm200 mm <br />0.2 m <br /> (100 cm1,000 mm <br />1 m <br />) +
well-developed +
D.C. +, Fla. +, N.Mex. +, Tex. +, La. +, Ala. +, Ind. +, Tenn. +, Nev. +, Va. +, Colo. +, Calif. +, Ark. +, Ill. +, Ariz. +, Ont. +, Ohio +, Utah +, Mo. +, Kans. +, Minn. +, Nebr. +, Okla. +, Miss. +, S.C. +  and Ky. +
capillary +
germination +
pistillate +  and staminate +
sometimes longer +
compressed +  and terete +
shorter or longer +
subtending +
unequal +
membranous +
0 +  and 10 +
uncinate +
bracteate +  and ebracteate +
solid +  and hollow +
pubescent +  and pilose +
cauline +  and basal +
coriaceous +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.11 cm1.1 mm <br />0.0011 m <br />) +
membranous +
inconspicuous +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
3mm +  and 4.3mm +
mucronate +, acuminate +  and lanceolate +
1.2mm +  and 1.7mm +
complex +  and simple +
concealed +  and prominent +
pubescent +  and puberulent +
2 +  and 5 +
2 +  and 1 +
6cm +  and 20cm +
subterranean +
0.3 cm3 mm <br />0.003 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
dry +  and fleshy +
elongate +
in triplets +  and paired +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
subterranean +
8 +  and 16 +
unisexual +  and bisexual +
lanceolate +
1.2mm +  and 1.7mm +
1 (?) +  and 3 (?) +
fused +  and free +
2 (?) +  and 3 (?) +
plumose +
dome--shaped +  and triangular +
Gramineae +
Eriochloa contracta +
Eriochloa +
species +
membranous +
glabrous +  and scabrous +
acute +  and rounded +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
not pronounced +
plant +  and cespitose +
aquatic +  and terrestrial +
dioecious +, monoecious +  and synoecious +