Dichanthelium portoricense |
Dichanthelium depauperatum |
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blunt-glumed panicgrass |
panic appauvri, starved panic grass, starved rosette-panicgrass |
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Habit | Plants usually densely cespitose. | Plants cespitose. | ||||
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. |
10-45 cm, erect to spreading, lower 4-10 internodes telescoped together, less than 2 cm, upper 2 internodes elongated; nodes bearded; internodes pubescent to subglabrous; fall phase a dense mass of erect blades and foreshortened branches that arise from the basal culm nodes, about 54 of the branches sterile, others with small, narrow, secondary panicles of 3-7 spikelets that remain enclosed within the sheaths. |
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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. |
2-4; sheaths longer than the internodes, glabrous or densely ascending-pilose; ligules about 0.5 mm; blades 6-15 cm long, 1-4 mm wide, green to grayish-green, sometimes involute, glabrous or densely pilose, apices long-tapering, lower blades small to vestigial, upper 2 or 3 blades longer and stiffly erect. |
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Spikelets | 1.5-2.6 mm, obovoid-pyriform, planoconvex in side view, puberulent, pubescent, or glabrous, attenuate basally, apices usually broadly rounded. |
3.2-4.3 mm long, 1-1.7 mm wide, ellipsoid-pointed, glabrous or finely pubescent. |
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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. |
1.2-1.6 mm, narrowly triangular; upper glumes and lower lemmas exceeding the upper florets by 0.2-1 mm, forming a pointed beak, upper florets 1.9-3.1 mm, obovoid, minutely umbonate. |
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Basal | rosettes well-differentiated; blades 1.5-6 cm, ovate to lanceolate. |
rosettes poorly differentiated; blades similar in shape to the lower cauline blades, narrow, ascending. |
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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, 1.5-3 cm wide, usually long-exserted (sometimes contracted and remaining basal), with 7-25 spikelets. |
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2n | = 18. |
= 18. |
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Dichanthelium portoricense |
Dichanthelium depauperatum |
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Distribution |
AL; AR; CO; CT; DC; DE; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NE; NH; NJ; NY; OH; OK; PA; RI; SC; TN; TX; VA; VT; WI; WV; WY; MB; NB; NS; ON; PE; QC
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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 depauperatum grows in dry, open woodlands and open, disturbed areas, especially on sand. It is restricted to the Flora region. The primary panicles, which are rarely open-pollinated, are produced from May to early June; the secondary, cleistogamous panicles are produced from late June through July (rarely in fall). The species is linked with D. perlongum and D. linearifolium by occasional hybrids and hybrid derivatives. In the northern United States and Canada, 80-90% of the plants are glabrous and have been called Panicum depauperatum var. psilophyllum Fernald, P. depauperatum var. involutum (Torr.) Alph. Wood, or, if the primary panicles remain near the base, P. depauperatum forma cryptostachys Fernald; in this treatment, none of these is recognized as a distinct taxonomic entity. The frequency of pilose plants increases southward, where some populations are entirely pilose. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 25, p. 441. | FNA vol. 25, p. 450. | ||||
Parent taxa | Poaceae > subfam. Panicoideae > tribe Paniceae > Dichanthelium > sect. Lancearia | Poaceae > subfam. Panicoideae > tribe Paniceae > Dichanthelium > sect. Linearifolia | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Panicum portoricense | Panicum depauperatum var. psilophyllum, Panicum depauperatum var. involutum, Panicum depauperatum | ||||
Name authority | (Desv. ex Ham.) B.E Hansen & Wunderlin | (Muhl.) Gould | ||||
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