Pennisetum polystachion

(L.) Schult.
Common names: Mission grass
Introduced
Treatment appears in FNA Volume 25.

Plants annual or perennial; cespitose from a hard, knotty base. Culms 30-200 cm, erect, branching; nodes glabrous. Sheaths glabrous, margins ciliate; ligules 1.5-2.7 mm; blades 15-55 cm long, 4-18 mm wide, flat, glabrous or pubescent. Panicles terminal, 10-25 cm long, 15-30 mm wide, fully exerted from the sheaths, erect to drooping, white, yellow, light-brown, or pink to deep purple; rachises terete, scabrous. Fascicles 33-45 per cm, disarticulating at maturity; fascicles axes 0.2-0.5 mm, with 1 spikelet; outer bristles 13-30, 1.3-5 mm, scabrous; inner bristles 6-14, 4.3-11.5 mm, long ciliate; primary bristles 14-25 mm, long-ciliate, noticeably longer than the other bristles. Spikelets 3-4.5 mm, sessile; lower glumes absent or to 2 mm, veinless; upper glumes 3-4.5 mm, glabrous, 5-7-veined, 3-lobed; lower florets sterile or staminate; lower lemmas 3-3.9 mm, 5-7-veined, apices lobed; lower paleas 2.9-3.7 mm; anthers absent or 1.7-2 mm; upper florets disarticulating at maturity; upper lemmas 1.7-3 mm, coriaceous, shiny, 5-veined, apices ciliate; anthers 1.3-2.1 mm. Caryopses about 1.7 mm, concealed by the lemma and palea at maturity. 2n = 18, 36, 45, 48, 52, 53, 54, 56, 78.

Distribution

Puerto Rico, Tex., Fla., Pacific Islands (Hawaii)

Discussion

Pennisetum polystachion is a polymorphic, weedy African species that has become established in the tropics and subtropics, including Florida. The U.S. Department of Agriculture considers it a noxious weed. Only Pennisetum polystachion subsp. setosum (Sw.) Brunken has been found in the Flora region. It differs from P. polystachion (L.) Schutt. subsp. polystachion as indicated:

Selected References

None.

Lower Taxa

None.

Key

1 Plants annual, usually profusely branching; fascicles white, pink, red, or deep purple Pennisetum polystachion subsp. polystachion
1 Plants perennial, usually sparingly branched; fascicles yellow, light brown, or purplish Pennisetum polystachion subsp. setosum

"decumbent" is not a number.

... more about "Pennisetum polystachion"
78 +, 56 +, 54 +, 53 +, 52 +, 48 +, 45 +, 36 +  and 18 +
0.13 cm1.3 mm <br />0.0013 m <br /> (0.21 cm2.1 mm <br />0.0021 m <br />) +
anatomy +  and kranz +
J.K. Wipff +
(L.) Schult. +
1 (?) +  and 3 (?) +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
divergent +  and parallel +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
pseudopetiolate +
non-radiate +  and radiate +
15 cm150 mm <br />0.15 m <br /> (55 cm550 mm <br />0.55 m <br />) +
pubescent +  and glabrous +
usually linear +  and lanceolate occasionally ovate +
0.4 cm4 mm <br />0.004 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
spikelike +
reduced +
0 cm0 mm <br />0 m <br /> (1 cm10 mm <br />0.01 m <br />) +
disarticulating +
fused +  and free +
not developed +
terete +  and compressed +
1.7 cm17 mm <br />0.017 m <br /> (?) +
sometimes longer +
Mission grass +
30 cm300 mm <br />0.3 m <br /> (200 cm2,000 mm <br />2 m <br />) +
not woody +
Puerto Rico +, Tex. +, Fla. +  and Pacific Islands (Hawaii) +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.75 cm7.5 mm <br />0.0075 m <br />) +
capillary +
germination +
pistillate +  and staminate +
sometimes longer +
compressed +  and terete +
shorter or longer +
subtending +
unequal +
membranous +
uncinate +
bracteate +  and ebracteate +
0.43 cm4.3 mm <br />0.0043 m <br /> (1.15 cm11.5 mm <br />0.0115 m <br />) +
usually flatter and wider +
hollow +  and solid +
cauline +  and basal +
coriaceous +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.27 cm2.7 mm <br />0.0027 m <br />) +
membranous +
inconspicuous +
0.3 cm3 mm <br />0.003 m <br /> (0.39 cm3.9 mm <br />0.0039 m <br />) +
0.29 cm2.9 mm <br />0.0029 m <br /> (0.37 cm3.7 mm <br />0.0037 m <br />) +
complex +  and simple +
concealed +  and prominent +
0.13 cm1.3 mm <br />0.0013 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
pink +  and deep purple +
10cm +  and 25cm +
subterranean +
erect +  and drooping +
1 +  and many +
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
dry +  and fleshy +
long-ciliate +  and scabrous +
1.4 cm14 mm <br />0.014 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
disarticulating +
Introduced +
in triplets +  and paired +
unisexual +  and bisexual +
compressed +  and terete +
0.3 cm3 mm <br />0.003 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
1 +  and 3 +
fused +  and free +
2 +  and 3 +
dome--shaped +  and triangular +
Gramineae +
Pennisetum polystachion +
Pennisetum +
species +
membranous +
0.3 cm3 mm <br />0.003 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
0.17 cm1.7 mm <br />0.0017 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
perennial +  and annual +
plant +  and cespitose +
aquatic +  and terrestrial +
dioecious +, monoecious +  and synoecious +
9 +, 8 +, 7 +  and 5 +