Dichanthelium boreale |
Dichanthelium portoricense |
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northern panicgrass, northern rosette-panicgrass, panic boreal |
blunt-glumed panicgrass |
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Habit | Plants cespitose. | Plants usually densely cespitose. | ||||
Culms | 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. |
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. |
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Cauline leaves | 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. |
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. |
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Spikelets | 2-2.2 mm long, 0.8-1.3 mm wide, ellipsoid, usually reddish, shortly pubescent, subacute. |
1.5-2.6 mm, obovoid-pyriform, planoconvex in side view, puberulent, pubescent, or glabrous, attenuate basally, apices usually broadly rounded. |
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Lower glumes | 0.5-1 mm, triangular-ovate; lower florets sterile; upper florets slightly exceeding the upper glumes and lower lemmas, subacute. |
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. |
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Basal | rosettes well-differentiated; blades 2-4 cm, pubescent, reddish. |
rosettes well-differentiated; blades 1.5-6 cm, ovate to lanceolate. |
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Primary | panicles 5-11 cm long, 3-8 cm wide, ovoid, long-exserted, with 40-220 spikelets. |
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. |
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2n | = 18. |
= 18. |
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Dichanthelium boreale |
Dichanthelium portoricense |
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Distribution |
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 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.) |
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.) |
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Key |
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Source | FNA vol. 25, p. 434. | FNA vol. 25, p. 441. | ||||
Parent taxa | Poaceae > subfam. Panicoideae > tribe Paniceae > Dichanthelium > sect. Dichanthelium | Poaceae > subfam. Panicoideae > tribe Paniceae > Dichanthelium > sect. Lancearia | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Panicum boreale var. michiganense, Panicum boreale | Panicum portoricense | ||||
Name authority | (Nash) Freckmann | (Desv. ex Ham.) B.E Hansen & Wunderlin | ||||
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