Aristida basiramea

Engelm. ex Vasey
Common names: Forktip threeawn Aristide à rameaux basilaires
Endemic
Treatment appears in FNA Volume 25. Treatment on page 326.

Plants annual. Culms 25-45 cm, erect, branching at most nodes. Leaves cauline; sheaths shorter than the internodes, glabrous or sparsely pilose; ligules about 0.3 mm; blades 3-8 cm long, 1-1.5 mm wide, flat to folded, becoming involute in age, adaxial surfaces with scattered pilose hairs, pale green. Inflorescences racemose or paniculate, (2) 4-10 cm long, 1-2 cm wide, with few (sometimes only 1 or 2) spikelets; primary branches weakly developed, to 2 cm, appressed, with 1-3 spikelets. Spikelets appressed, only slightly overlapping. Glumes 1-veined, acute, awned, awns 1-2 mm, brown to purplish; upper glumes 10-12 mm; lower glumes 1-2 mm shorter; calluses 0.4-0.6 mm; lemmas 8-9 mm, light gray, mottled; awns erect to divergent; central awns 10-15 mm, with 2-3 spiral coils at the base; lateral awns 5-10 mm, not coiled but often curved and twisted basally, strongly divergent distally; anthers 3, about 3 mm, purplish-brown. Caryopses 6-7 mm, light chestnut-brown. 2n = unknown.

Distribution

Wis., Ont., Que., Miss., Tenn., Fla., N.H., Tex., N.Dak., N.Y., Colo., Ala., Mass., Maine, Vt., Ill., Ind., Iowa, Kans., Nebr., Okla., Pa., S.C., W.Va., Mo., Minn., Mich.

Discussion

Aristida basiramea grows in open, sandy, often barren ground in southern Ontario and in the United States. It is similar to A. dichototna, differing in its longer lateral awns. Further study may show that the two should be treated as conspecific varieties.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Aristida basiramea"
purplish-brown +
3 cm30 mm <br />0.03 m <br /> (?) +
Kelly W. Allred +
Engelm. ex Vasey +
1 (?) +  and 3 (?) +
brown;purplish +
straight +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
keeled +  and rounded +
coiled +, disarticulating +  and twisted +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
straight +
3 cm30 mm <br />0.03 m <br /> (8 cm80 mm <br />0.08 m <br />) +
flat +  and folded +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
spikelike +
well-developed +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
light chestnut-brown +
0.6 cm6 mm <br />0.006 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
non-radiate +  and radiate +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
Forktip threeawn +  and Aristide à rameaux basilaires +
25 cm250 mm <br />0.25 m <br /> (45 cm450 mm <br />0.45 m <br />) +
not woody +
Wis. +, Ont. +, Que. +, Miss. +, Tenn. +, Fla. +, N.H. +, Tex. +, N.Dak. +, N.Y. +, Colo. +, Ala. +, Mass. +, Maine +, Vt. +, Ill. +, Ind. +, Iowa +, Kans. +, Nebr. +, Okla. +, Pa. +, S.C. +, W.Va. +, Mo. +, Minn. +  and Mich. +
large +  and small +
capillary +
germination +
pistillate +  and staminate +
sometimes longer +
compressed +  and terete +
subtending +
paniculate +  and racemose +
4 cm40 mm <br />0.04 m <br /> (?) +  and 10 cm100 mm <br />0.1 m <br /> (?) +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
twisted +  and not coiled +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
mottled +  and light gray +
scabridulous +
fusiform +
0.8 cm8 mm <br />0.008 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
coriaceous +
indistinguishable +
0.3 cm3 mm <br />0.003 m <br /> (?) +
inconspicuous +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
concealed +  and prominent +
2 +  and 1 +
concealing +
0 +  and 1/2 +
dry +  and fleshy +
divaricate +  and divergent +
ascending;usually appressed;ascending +
0 cm0 mm <br />0 m <br /> (2 cm20 mm <br />0.02 m <br />) +
not prolonged +
pilose +  and glabrous +
1 (?) +  and Anatomy (?) +
1 +  and 3 +
triangular +  and dome--shaped +
2 (?) +  and 3 (?) +
Gramineae +
Aristida basiramea +
Aristida +
species +
membranous +
1 cm10 mm <br />0.01 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
aquatic +  and terrestrial +