Dichanthelium strigosum |
Dichanthelium boreale |
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cushion-tuft panicgrass, roughhair rosette grass |
northern panicgrass, northern rosette-panicgrass, panic boreal |
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Habit | Plants densely cespitose. | Plants cespitose. | ||||||||
Culms | 5-45 cm, slender, erect or spreading; from a dense tuft of predominantly basal leaves, lower internodes short, upper 3-5 internodes elongate; nodes glabrous or bearded; internodes glabrous or pilose; fall phase with spreading culms and branches arising from near the bases forming a dense, flat tuft. |
18-75 cm, usually more than 1 mm thick, occasionally delicate, erect or ascending; nodes glabrous; internodes glabrous; fall phase with decumbent culms, branches arising from the lower and midculm nodes, rebranching 2-3 times, with small blades and secondary panicles compared to those on the culms, secondary panicles with 8-10 spikelets, partially included at maturity. |
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Cauline leaves | 2-4; lower cauline sheaths longer than the internodes, mostly glabrous or pilose with ascending hairs, margins finely ciliate; ligules 0.2-2 mm, at low magnification appearing to be membranous and ciliate, at high magnification evidently of hairs that are coherent at the base; blades 1.5-6 cm long, 3-8 mm wide, lanceolate, glabrous or softly pilose, margins with prominent papillose-based cilia, at least basally. |
3-5; sheaths shorter than the internodes, lower sheaths pubescent, upper sheaths glabrous, margins of all sheaths sparsely ciliate; ligules about 0.5 mm, of hairs; blades 5-11 cm long, 5-13 mm wide, thin, spreading to erect, usually glabrous, rarely pubescent abaxially, always glabrous adaxially, bases truncate to cordate, ciliate on the margins, blades of the flag leaves erect or ascending. |
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Spikelets | 1.1-2.1 mm, obovoid to broadly ellipsoid, glabrous or pubescent, hairs not papillose-based. |
2-2.2 mm long, 0.8-1.3 mm wide, ellipsoid, usually reddish, shortly pubescent, subacute. |
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Lower glumes | 1/3 - 1/2 as long as the spikelets, acute to obtuse; upper florets 0.8-1.7 mm, ellipsoid, subacute. |
0.5-1 mm, triangular-ovate; lower florets sterile; upper florets slightly exceeding the upper glumes and lower lemmas, subacute. |
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Basal | rosettes poorly differentiated; blades 1-5 cm, lanceolate, grading into the cauline blades. |
rosettes well-differentiated; blades 2-4 cm, pubescent, reddish. |
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Primary | panicles short- to long-exserted; rachises and branches often pilose. |
panicles 5-11 cm long, 3-8 cm wide, ovoid, long-exserted, with 40-220 spikelets. |
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2n | = 18. |
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Dichanthelium strigosum |
Dichanthelium boreale |
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Distribution |
AL; FL; GA; LA; MS; NC; SC; TN; TX; VA; PR
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CT; DC; GA; IA; IL; IN; KY; MA; MD; ME; MI; MN; MO; NC; NH; NJ; NY; OH; PA; RI; TN; VA; VT; WI; WV; LB; NB; NS; ON; PE; QC
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Discussion | Dichanthelium strigosum extends from the southeastern Flora region south into Mexico, the Caribbean, and into northern South America. The primary panicles are briefly open-pollinated in April or May; the secondary panicles, which are produced from May through November, are cleistogamous. The three subspecies are mostly sympatric and sometimes grow together, with occasional intergradation. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Dichanthelium boreale grows in open woodlands and thickets, wet meadows, and fields. It is restricted to the Flora region. The primary panicles are mostly open-pollinated and are produced in May and June; the secondary panicles are predominantly cleistogamous and are produced from mid-June into October. Dichanthelium boreale occasionally hybridizes with D. acuminatum and D. xanthophysum, producing a sterile triploid sometimes called Panicum calliphyllum Ashe. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 25, p. 446. | FNA vol. 25, p. 434. | ||||||||
Parent taxa | Poaceae > subfam. Panicoideae > tribe Paniceae > Dichanthelium > sect. Strigosa | Poaceae > subfam. Panicoideae > tribe Paniceae > Dichanthelium > sect. Dichanthelium | ||||||||
Sibling taxa | ||||||||||
Subordinate taxa | ||||||||||
Synonyms | Panicum strigosum | Panicum boreale var. michiganense, Panicum boreale | ||||||||
Name authority | (Muhl. ex Elliott) Freckmann | (Nash) Freckmann | ||||||||
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