Danthonia compressa

Austin
Common names: Flattened oatgrass Danthonie comprimée
Endemic
Synonyms: Danthonia alleni
Treatment appears in FNA Volume 25. Treatment on page 303.

Culms 40-80 cm, disarticulating at the nodes when mature. Sheaths glabrous, rarely sparsely pilose, usually reddish above the nodes; blades to 30 cm long, 2-4 mm wide, flexible but not curled at maturity, glabrous, sometimes scabrous, uppermost cauline blades erect to ascending. Inflorescences with (4) 6-17 spikelets; branches usually flexible, usually divergent, sometimes strongly so, after anthesis; lower branches with 2-3 spikelets; pedicels on the lowest branch as long as or longer than the spikelets. Spikelets (7) 10-16 mm. Calluses of middle florets about as long as wide, convex abaxially; lemma bodies 2.5-5 mm, pilose over the back, sometimes sparsely so, margins pilose to beyond midlength, distal hairs 0.5-2 mm, apical teeth 2-4 mm, aristate, (1/2) 2/3 or more as long as the lemma bodies; awns 6-10 mm; anthers to 2.2 mm. Caryopses 1.7-2.6 mm long, 0.7-1.1 mm wide. 2n = 36.

Distribution

Conn., N.J., N.Y., D.C., W.Va., Ark., Del., N.C., S.C., Tenn., Pa., N.S., Ont., P.E.I., Que., Va., Mass., Maine, N.H., R.I., Vt., Alaska, Ala., Ga., Md., Ohio, Mich., Ky.

Discussion

Danthonia compressa grows in open and semi-shaded areas, including meadows, open woods, and woodland openings. Although not a true pioneer species, it may sometimes occur as a weed in perennial crops. It is restricted to eastern North America.

Selected References

None.

Lower Taxa

None.

"wide" is not a number."decumbent" is not a number.

... more about "Danthonia compressa"
0 cm0 mm <br />0 m <br /> (0.22 cm2.2 mm <br />0.0022 m <br />) +
obtuse +, awned +  and mucronate +
2/3 +  and [1/2] +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Stephen J. Darbyshire +
Austin +
1 (?) +  and 3 (?) +
geniculate +
0.6 cm6 mm <br />0.006 m <br /> (1 cm10 mm <br />0.01 m <br />) +
pilose +  and glabrous +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
not pseudopetiolate +
0 cm0 mm <br />0 m <br /> (30 cm300 mm <br />0.3 m <br />) +
not curled +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
hirsute +  and scabrous +
spikelike +
0.17 cm1.7 mm <br />0.0017 m <br /> (0.26 cm2.6 mm <br />0.0026 m <br />) +
flattened +, ovate +  and obovate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.11 cm1.1 mm <br />0.0011 m <br />) +
not disarticulating +
Flattened oatgrass +  and Danthonie comprimée +
disarticulating +
perennial +  and annual +
40 cm400 mm <br />0.4 m <br /> (80 cm800 mm <br />0.8 m <br />) +
woody +  and herbaceous +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Conn. +, N.J. +, N.Y. +, D.C. +, W.Va. +, Ark. +, Del. +, N.C. +, S.C. +, Tenn. +, Pa. +, N.S. +, Ont. +, P.E.I. +, Que. +, Va. +, Mass. +, Maine +, N.H. +, R.I. +, Vt. +, Alaska +, Ala. +, Ga. +, Md. +, Ohio +, Mich. +  and Ky. +
small +  and large +
capillary +
sometimes longer +
1 +, 3 +  and 12 +
compressed +
cleistogamous +  and chasmogamous +
(1)3-7-veined +
subtending +
subequal +
non-uncinate +
1/3 +  and 3/4 +
spicate +  and ebracteate +
racemose +  and paniculate +
solid +  and hollow +
scabrous +  and glabrous +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
scabrous +  and glabrous +
rounded +
coriaceous +
acute +  and aristate +
inconspicuous +
with a few hairs +  and glabrous +
extended +
concealed +  and prominent +
2 +  and 1 +
well-developed +
sometimes slightly longer +
hirsute +  and scabrous +
dry +  and fleshy +
0 cm0 mm <br />0 m <br /> (12 cm120 mm <br />0.12 m <br />) +
hirsute +  and scabrous +
pilose +  and glabrous +
sterile +, bisexual +  and unisexual +
compressed +  and terete +
1 cm10 mm <br />0.01 m <br /> (1.6 cm16 mm <br />0.016 m <br />) +
1 +  and 3 +
2 (?) +  and 3 (?) +
Danthonia alleni +
Danthonia compressa +
Danthonia +
species +
membranous +
plant +  and cespitose +
aquatic +  and terrestrial +