Heteropogon contortus

(L.) P. Beauv. ex Roem. & Schult.
Common names: Tanglehead
Introduced
Synonyms: Andropogon contortus
Treatment appears in FNA Volume 25. Treatment on page 680.

Plants perennial. Culms 20-150 cm, erect. Sheaths smooth, reddish; ligules 0.5-0.8 mm, cilia 0.2-0.5 mm; blades 10-15 cm long, 2-7 mm wide, flat or folded, glabrous or pubescent. Rames 3-7 cm, secund, with 12-22, brown to reddish-brown, sessile-pedicellate spikelet pairs. Homogamous spikelets 6-10 mm. Heterogamous spikelets: sessile spikelets 5-10 mm, brown, awned; calluses 1.8-2 mm, strigose; awns 6-10 cm; pedicellate spikelets 6-10 mm, unawned; glumes ovatelanceolate, glabrous or with papillose-based hairs distally, without glandular pits, greenish to purplish-brown, becoming stramineous when dry. 2n = 40, 50, 60.

Distribution

N.Mex., Tex., Calif., Puerto Rico, Virgin Islands, Pacific Islands (Hawaii), Ariz., Fla.

Discussion

Heteropogon contortus grows on rocky hills and canyons in the southern United States into Mexico, and worldwide in subtropical and tropical areas, occupying a variety of different habitats, including disturbed habitats. It is probably native to the eastern hemisphere but is now found in tropical and subtropical areas throughout the world.

Heteropogon contortus is a valuable forage grass if continuously grazed so as to prevent the calluses from developing. It is also considered a weed, being able to establish itself in newly disturbed and poor soils.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Heteropogon contortus"
60 +, 50 +  and 40 +
anatomy +  and kranz +
Mary E. Barkworth +
(L.) P. Beauv. ex Roem. & Schult. +
1 (?) +  and 3 (?) +
conspicuous +
geniculate +
6 cm60 mm <br />0.06 m <br /> (10 cm100 mm <br />0.1 m <br />) +
slender +
keeled +  and rounded +
pseudopetiolate +  and branching +
divergent +  and parallel +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
non-radiate +  and radiate +
brown +  and reddish-brown +
well-developed +
10 cm100 mm <br />0.1 m <br /> (15 cm150 mm <br />0.15 m <br />) +
pubescent +  and glabrous +
folded +  and flat +
reduced +
3 cm30 mm <br />0.03 m <br /> (7 cm70 mm <br />0.07 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
spikelike +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
lanceolate +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
Tanglehead +
branched +  and simple +
purple +  and reddish +
20 cm200 mm <br />0.2 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
not woody +
N.Mex. +, Tex. +, Calif. +, Puerto Rico +, Virgin Islands +, Pacific Islands (Hawaii) +, Ariz. +  and Fla. +
capillary +
sometimes longer +
concealing +
compressed +  and terete +
stramineous +, greenish +  and purplish-brown +
shorter or longer +
subtending +
with papillose-based hairs +  and glabrous +
ovatelanceolate +
unequal +
membranous +  and coriaceous +
papillose-based +
golden brown +
uncinate +
bracteate +  and ebracteate +
pedunculate +  and multiple-stalked +
solid +  and hollow +
photosynthetic +
smelling +  and aromatic +
coriaceous +
ciliate +  and glabrous +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
membranous +
inconspicuous +
complex +  and simple +
concealed +  and prominent +
pedicellate +
dry +  and fleshy +
elongate +
Introduced +
pedicellate +, sessile +  and sessile-pedicellate +
in triplets +  and paired +
1/4 +  and 2/3 +
heterogamous +  and homogamous +
0.6 cm6 mm <br />0.006 m <br /> (1 cm10 mm <br />0.01 m <br />) +
heterogamous +, sterile +  and homogamous +
1 +  and 3 +
fused +  and free +
2 +  and 3 +
dome--shaped +  and triangular +
Andropogon contortus +
Heteropogon contortus +
Heteropogon +
species +
membranous +
sessile-pedicellate +
3-veined +  and sulcate +
aquatic +  and terrestrial +
dioecious +, monoecious +  and synoecious +