Dichanthelium portoricense |
Dichanthelium pedicellatum |
|||||
---|---|---|---|---|---|---|
blunt-glumed panicgrass |
cedar rosette grass, corm-based panicgrass |
|||||
Habit | Plants usually densely cespitose. | Plants cespitose, not rhizoma-tous. | ||||
Culms | 15-50 cm, slender, wiry; internodes olive green to purplish, densely puberulent or glabrous; fall phase spreading or decumbent, branching extensively from the lower and midculm nodes, producing numerous congested fascicles of reduced, flat or involute blades and reduced secondary panicles. |
20-70 cm, initially erect, with hard, cormlike bases; nodes puberulent to sparsely hirsute; internodes all elongated, puberulent to hirsute; fall phase with decumbent culms, developing divaricate branches from the midculm nodes before the primary panicles mature. |
||||
Cauline leaves | 4-7; sheaths much shorter than the internodes, densely crisp-puberulent, velvety-puberulent, or glabrous, often ciliate along the margins; ligules shorter than 0.5 mm; blades 2-7 cm long (seldom longer), 2.5-8 mm wide (rarely wider), spreading, firm, flat or slightly involute, without prominently raised veins, not longitudinally wrinkled, densely puberulent or glabrous abaxially, glabrous, sparsely puberulent, or pubescent adaxially, bases subcordate, with papillose-based cilia, margins often whitish and scabridulous. |
4-7; sheaths sometimes overlapping, puberulent to papillose-hispid, margins ciliate; ligules 0.3-1 mm, membranous and ciliate; blades 3-12 cm long, 2-8 mm wide, widening distal to the rounded or subcordate bases, thin, glabrous or sparsely hirsute, margins with papillose-based cilia. |
||||
Spikelets | 1.5-2.6 mm, obovoid-pyriform, planoconvex in side view, puberulent, pubescent, or glabrous, attenuate basally, apices usually broadly rounded. |
3.2-4.4 mm long, 1.3-1.6 mm wide, narrowly obovoid-ellipsoid, papillose-hirsute, attenuate to the purplish bases. |
||||
Lower glumes | 0.6-1.4 mm, thin, weakly-veined, attached about 0.2 mm below the upper glumes, clasping at the base; upper glumes as long as or slightly shorter than the lower lemmas; upper florets 1.4-2 mm, broadly ellipsoid, apices subacute, minutely puberulent. |
about 1/2 as long as the spikelets, narrowly triangular, subadjacent to the upper glumes, not encircling the pedicels; upper glumes about 0.3 mm shorter than the upper florets; lower florets sterile; upper florets with pointed, minutely puberulent apices. |
||||
Basal | rosettes well-differentiated; blades 1.5-6 cm, ovate to lanceolate. |
rosettes absent. |
||||
Primary | panicles 2-7 cm long, 2/3 to nearly as wide as long, with relatively few spikelets, exserted; branches flexuous, spreading or reflexed, scabridulous to densely puberulent. |
panicles 3-6 cm long, 2-4 cm wide, exserted; branches spreading at maturity; pedicels somewhat divergent. |
||||
2n | = 18. |
= 18. |
||||
Dichanthelium portoricense |
Dichanthelium pedicellatum |
|||||
Distribution |
TX |
|||||
Discussion | Dichanthelium portoricense grows in sandy woods, low pinelands, savannahs, and coastal sand dunes, usually in moist places. Its range extends south from the Flora region into Mexico, the Caribbean, and Mesoamerica. It is a highly variable species with numerous intergrading forms, some possibly resulting from hybridization with other widespread species in the same region, such as D. sphaerocarpon and D. commutatum. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Dichanthelium pedicellatum grows on limestone outcroppings and in dry, open oak woodlands. Its range extends from Texas into Mexico and Guatemala. Primary panicles develop from late March into June (and sometimes from late August to November) and are open-pollinated; secondary panicles develop from May into fall and are at least partly cleistogamous. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
||||
Key |
|
|||||
Source | FNA vol. 25, p. 441. | FNA vol. 25, p. 410. | ||||
Parent taxa | Poaceae > subfam. Panicoideae > tribe Paniceae > Dichanthelium > sect. Lancearia | Poaceae > subfam. Panicoideae > tribe Paniceae > Dichanthelium > sect. Pedicellata | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Panicum portoricense | Panicum pedicellatum | ||||
Name authority | (Desv. ex Ham.) B.E Hansen & Wunderlin | (Vasey) Gould | ||||
Web links |