keys to the vascular plants of east texas - Botanical Research ...

1026 POACEAE/PENNISETUM
bristles 2.2–10(–14) mm long, glabrous or scabrous; primary bristles to ca. 24 mm long; spikelets
1–6(–10) per cluster, 4.4–6.7 mm long; lower glume 1–2.2 mm long, the upper ca. 3–4.8(–5.5)
mm long. Introduced as a cultivated grass (Hatch et al. 1999) and apparently escaping; included
based on citation of Post Oak Savannah by Hatch (2002); Turner et al. (2003) also mapped
Brazos Co., but all Brazos Co. specimens we have been able to find in TX herbaria were cultivated;
also reported as escaped in the Gulf Prairies and Marshes (Hatch et al. 1999); no county
distribution map is provided; in the U.S., records of escapes are known only from TX
(Barkworth et al. 2002). May–Nov. Native to w Himalayas of India w through Asia Minor and n
Africa to Morocco (Ramu et al. 1996). This species is known to hybridize with P. ciliare (Ramu
et al. 1996). It reproduces at least partially through apomixis (= method of vegetative reproduction
in which an embryo is formed without fertilization) (Ramu et al. 1996). It has been described
as being potentially important as an ornamental grass and also as a possible source of
germplasm for forage crop improvement programs (Ramu et al. 1996). I
Pennisetum purpureum Schumach., (purple), ELEPHANT GRASS, NAPIER GRASS. Robust, stoloniferous,
tufted perennial; culms (1–)2–4+ m tall, usually much-branched; nodes glabrous or pubescent;
internodes glaucous; ligule membranous, ciliate, to 5 mm long; leaf blades (4–)12–40 mm
wide; inflorescence 7–25(–30) cm long, 1–3 cm wide (excluding bristles), golden yellow or dark
purple, the axis straight; peduncle (at point just below inflorescence) distinctly hairy; bristles of
involucre usually less than 1.7(–4) cm long, scabrous, the inner ones plumose toward base;
spikelets 4.4–7 mm long, 1–5 per cluster, 1 fertile and nearly sessile, the others, if present, staminate
and pedicelled; lower glume minute or obsolete, 0.8 mm or less long, the upper glume usually
1/4–1/3 the length of the spikelet. Cultivated for pasture, also a weed along roadsides
(planted for erosion control by highway dept.?); known in East TX only from Grayson (J.A.
Crosthwaite s.n., BRIT) and Bexar (Turner et al. 2003) cos.; Turner et al. (2003) also mapped
Brazos Co., but all Brazos Co. material we have been able to find in TX herbaria was cultivated;
also Gulf Prairies and Marshes; FL and TX. Oct–Nov. Native of tropical Africa. This species is
reported to be highly productive for forage but becomes unpalatable at maturity (Hatch et al.
1999) because the mature leaves have razor-sharp margins (Bor 1960). When mature, the culms
are “reed-like” and have been used in building fences, walls of huts, etc. (Bor 1960). After recognition
for its value as a forage early in the 20th century, this species “… was introduced to most
of the world’s wet tropics where it has frequently escaped and has become naturalized”
(Brunken 1977). I
Pennisetum setaceum (Forssk.) Chiov., (bristle-like), TENDER FOUNTAIN GRASS, FOUNTAIN GRASS,
CRIMSON FOUNTAIN GRASS. Perennial, tufted; culms to 100(–150) cm tall; leaf blades 3.5 mm or
less wide, green, the midvein noticeably thickened; inflorescence usually 15–30 cm long, plumose,
pink to dark burgundy; bristles of involucre plumose toward base, one bristle of each involucre
longer than the others, the longest ca. 3 cm long; spikelets 1–4 per cluster, 4.5–6.5 mm
long; lower glume usually absent (rarely to 0.3 mm long). Widely cultivated as an ornamental;
included based on citation of Post Oak Savannah by Hatch (2002) and Brazos Co. by Barkworth
et al. (2002); we have, however, seen no escaped specimens from East TX; no county distribution
map is provided; AZ, CA, FL, KY, LA, NM, TN, and TX. Summer. Native of the e Mediterranean.
This species can be invasive and is listed as a noxious weed in HI (Kartesz 1999). � I
Pennisetum villosum R. Br. ex Fresen., (softly hairy), FEATHER-TOP, FEATHER-TOP PENNISETUM. Perennial,
tufted; culms 20–75 cm tall; ligule a ciliate membrane with hairs ca. 1–1.5 mm long; leaf
blades 2–5 mm wide; inflorescence a relatively short, � ovate, contracted panicle, whitish, tan,
or yellowish, feathery, 4–10(–12) cm long; spikelet clusters 7–11 per cm of inflorescence axis;
bristles of involucre usually 4–5(–7) cm long, the inner bristles plumose with silky hairs; spikelets
1(–4) per cluster, large, (7–)9–12(–15) mm long. Cultivated as an ornamental, tending to persist
or become a transitory escape; Dallas, Travis (BRIT), Bexar (TEX), and Bell (Turner et al.
2003) cos.; Turner et al. (2003) also mapped Brazos Co., but all Brazos Co. material we have been