Dichanthelium aciculare |
Dichanthelium depauperatum |
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narrow-leaf panicgrass, needleleaf rosette grass |
panic appauvri, starved panic grass, starved rosette-panicgrass |
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Habit | Plants grayish-green, cespitose, with caudices. | Plants cespitose. | ||||||||||||
Culms | 15-75 cm, erect; nodes glabrous or sparsely pubescent; internodes glabrous or puberulent to pilose basally; fall phase with erect to spreading culms, extensively branched from the mid- and upper culm nodes, eventually producing flabellate clusters of reduced, flat or involute blades. |
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 | 3-7; sheaths shorter than the internodes, glabrous or with soft, ascending, papillose-based hairs; ligules 0.5-2 mm, of hairs; lower blades 4-16 cm long, 3-9 mm wide, stiffly ascending to erect, glabrous or sparsely pilose to pubescent, with prominent raised veins, flat or longitudinally wrinkled, blades of the flag leaves often greatly reduced, often involute. |
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 | 1.7-3.6 mm long, 1.2-1.8 mm wide, obovoid to ellipsoid, biconvex in side view, glabrous or pubescent, bases narrow to attenuate, apices blunt or pointed to beaked. |
3.2-4.3 mm long, 1-1.7 mm wide, ellipsoid-pointed, glabrous or finely pubescent. |
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Lower glumes | thin, weakly veined, about 1/3 as long as the spikelets, attached to 0.5 mm below upper glumes, clasping at the base, broadly triangular to rounded; upper glumes with 5-9 prominent veins; lower florets sterile; upper florets apiculate. |
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 poorly differentiated; blades usually large, ovate to lanceolate, often transitional to the cauline blades. |
rosettes poorly differentiated; blades similar in shape to the lower cauline blades, narrow, ascending. |
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Primary | panicles 2-10 cm long, 0.5-7 cm wide, open or contracted, well-exserted. |
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 aciculare |
Dichanthelium depauperatum |
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Distribution |
AL; AR; DC; DE; FL; GA; IN; KY; LA; MD; MS; NC; NJ; NY; OK; PA; SC; TN; TX; VA; WV; PR
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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 aciculare grows in sandy, open areas in the southeastern United States, the West Indies and the Caribbean, southern Mexico, Central America, and northern South America. It has not been reported from northern Mexico. The primary panicles are open-pollinated (sometimes briefly) and develop from April to June; the secondary panicles are cleistogamous and develop from May into late fall. The subspecies are often distinct when growing together, perhaps maintained by the predominant autogamy, but they are more difficult to separate over wider geographic areas. Rare, partly fertile putative hybrids with Dichanthelium consanguineum, D. acuminatum, D. ovale, D. portoricense, and (possibly) D. dichotomum apparently lead to some intergradation with these species. (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. 442. | FNA vol. 25, p. 450. | ||||||||||||
Parent taxa | Poaceae > subfam. Panicoideae > tribe Paniceae > Dichanthelium > sect. Angustifolia | Poaceae > subfam. Panicoideae > tribe Paniceae > Dichanthelium > sect. Linearifolia | ||||||||||||
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Subordinate taxa | ||||||||||||||
Synonyms | Panicum aciculare | Panicum depauperatum var. psilophyllum, Panicum depauperatum var. involutum, Panicum depauperatum | ||||||||||||
Name authority | (Desv. ex Poir.) Gould & C.A. Clark | (Muhl.) Gould | ||||||||||||
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