Poa chapmaniana

Scribn.
Common names: Chapman's bluegrass
Endemic
Treatment appears in FNA Volume 24. Treatment on page 534.
Please click on the illustration for a higher resolution version.
Illustrator: Sandy Long

Copyright: Utah State University

Plants annual; densely tufted, tuft bases narrow, not stoloniferous, not rhizomatous. Culms 5-30 (40) cm tall, 0.3-0.7 mm thick, erect or the bases geniculate; nodes terete, usually 1 exserted. Sheaths closed for 1/10 – 1/2 their length, terete or weakly compressed, smooth; ligules 0.7-5 mm, decurrent, truncate to acute; blades of innovations and culms similar, 2-5 (8) cm long, 0.6-2.8 mm wide, flat or folded, thin, soft, smooth, margins scabrous, apices narrowly prow-shaped. Panicles 2-9.6 cm, erect, eventually open, moderately to densely congested, with 1-4 (7) branches per node; branches eventually ascending to spreading, rarely reflexed, terete, smooth or sparsely scabrous, spikelet-bearing to near the base or middle. Spikelets (2) 2.4-4.5 mm, laterally compressed; florets (1) 2-6; rachilla internodes usually shorter than 0.7 mm, smooth or scabrous, glabrous. Glumes subequal, about 3/4 as long as to subequal to the adjacent lemmas, lanceolate, thin, distinctly keeled, keels scabrous; lower glumes 1-3-veined; calluses webbed; lemmas 1.9-3 mm, broadly lanceolate, distinctly keeled, smooth, keels and marginal veins short to long-villous, hairs on the keels extending to near the apices, lateral-veins obscure, usually softly puberulent, intercostal regions usually sparsely softly puberulent, apices obtuse to acute; palea keels softly puberulent to long-villous at midlength, scabrous near the apices; anthers 1, 0.1-0.2 (0.3) mm. 2n = unknown.

Distribution

Del., W.Va., Fla., Tex., La., Kans., Nebr., Tenn., N.C., S.C., N.Y., Va., Ala., Ark., Ill., Ga., Ind., Iowa, Okla., Md., Mass., Ohio, Mo., Miss., Ky.

Discussion

Poa chapmaniana is native from the central part of the Great Plains east and southward to the coast. It grows in dry to mesic forests, forest openings, and the margins of bottomlands, often in disturbed ground and on acidic substrates. Records from New York probably represent introductions. Its web and single short anther distinguish P. chapmaniana from P. annua (p. 520) and most plants of P. bigelovii. It also differs from P. bigelovii (see below), probably its closest relative, in having narrower leaf blades, and panicle branches that are eventually spreading.

Selected References

None.

Lower Taxa

None.

"thin" is not a number.No values specified."decumbent" is not a number.No values specified.

... more about "Poa chapmaniana"
membranous +  and scarious +
puberulent +, hispidulous +, hairy +  and glabrous +
0.3 cm3 mm <br />0.003 m <br /> (?) +
1.5mm +  and 3mm +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.02 cm0.2 mm <br />2.0e-4 m <br />) +
scarious-hyaline +
obtuse +  and acute +
Robert J. Soreng +
Scribn. +
1 (?) +  and 3 (?) +
straight +
basal +  and terminal +
keeled +  and rounded +
strigose +  and glabrous +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
geniculate +
swelling +
not evident +
involute +, folded +  and flat +
reflexed;eventually ascending;spreading +
hispidulous +, glabrous +, smooth or +  and sparsely densely scabrous +
0.5 cm5 mm <br />0.005 m <br /> (20 cm200 mm <br />0.2 m <br />) +
compressed +  and terete +
folded +  and flat +
Chapman's bluegrass +
unbranched +  and hollow +
5 cm50 mm <br />0.05 m <br /> (30 cm300 mm <br />0.3 m <br />) +
compressed +  and terete +
2 cm20 mm <br />0.02 m <br /> (120 cm1,200 mm <br />1.2 m <br />) +
not woody +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
Del. +, W.Va. +, Fla. +, Tex. +, La. +, Kans. +, Nebr. +, Tenn. +, N.C. +, S.C. +, N.Y. +, Va. +, Ala. +, Ark. +, Ill. +, Ga. +, Ind. +, Iowa +, Okla. +, Md. +, Mass. +, Ohio +, Mo. +, Miss. +  and Ky. +
1/4 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
2 +  and 6 +
compressed +
reduced +
1-3(5)-veined +
shorter or longer +
subtending +
keeled +  and lanceolate +
subequal +
distributed +
puberulent +
uncinate +
0.1 cm1 mm <br />0.001 m <br /> (?) +
0 +  and 1/6 +
Oval (?) +  and Round (?) +
2 cm20 mm <br />0.02 m <br /> (5 cm50 mm <br />0.05 m <br />) +
milky white +  and slightly greenish +
long-villous +
obscure +  and prominent +
5(7-11)-veined +
hairy +  and glabrous +
keeled +  and lanceolate +
0.19 cm1.9 mm <br />0.0019 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
membranous +
erose +  and entire +
milky white +
ciliolate +  and smooth +
truncate +  and acute +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
membranous +
inconspicuous +
lobed +  and lanceolate +
milky white +
glabrous +, scabrous +  and smooth +
concealed +  and prominent +
2 +  and 1 +
well-developed +
2-keeled +
subequal +
1 cm10 mm <br />0.01 m <br /> (?) +
spikelike +
2 cm20 mm <br />0.02 m <br /> (9.6 cm96 mm <br />0.096 m <br />) +
dry +  and fleshy +
glabrous +, scabrous +  and smooth +
compressed +  and terete +
branching +, rhizomatous +  and stoloniferous +
many +, 1 +  and 100 +
compressed +
0.24 cm2.4 mm <br />0.0024 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Gramineae +
Poa chapmaniana +
Poa sect. Homalopoa +
species +
membranous +
parallel +  and converging +
aquatic +  and terrestrial +