Part 3, 1915] POACKAE 



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183. Panicum Scribnerianum Nash, Bull. Torrey Club 22: 421. 1895. 



Panicum macrocarpon Torr. Fl. U. S. 143. 1823. Not P. macrocarpon LeConte, 1819. 



Vernal phase in clumps of few to many culms, 20-50 cm. high, erect or ascending, often 

 geniculate at base, glabrous or harshly puberulent or sometimes ascending papillose-pilose; 

 leaf-sheaths rather loose, conspicuously striate, ciliate on the margin, ascending-pubescent 

 between the nerves and papillose-hispid with spreading or ascending hairs to nearly glabrous, 

 the papillae often without hairs; ligule about 1 mm. long; blades ascending or erect, 5-10 cm. 

 long, 6-12 mm. wide, usually firm, acuminate, rounded and ciliate at base, glabrous on the 

 upper surface, appressed-pubescent to glabrous beneath; panicles short-exserted, 4-8 cm. long, 

 rarely longer, two thirds to three fourths as wide, the flexuous branches ascending ; spikelets 3 .2- 

 3.3 mm. long, 2 mm. wide, obovate, turgid, blunt, sparsely pubescent to nearly glabrous; first 

 glume about one third the length of the spikelet, acute ; second glume and sterile lemma sub- 

 equal, barely or scarcely equaling the fruit at maturity, strongly nerved; fruit 2.8-2.9 mm. long, 

 1.8-1.9 mm. wide, broadly elliptic, minutely apiculate. 



Autumnal phase branching from the middle and upper nodes at about the maturity of the 

 primary panicle; the branches longer than the internodes, and late in the season producing 

 crowded branchlets with ascending, not greatly reduced, blades and small, partially included, 

 panicles from their upper nodes. 



Type locality: Pennsylvania. 



Distribution: Maine to British Columbia, and south to Maryland and Arizona. 



Illustrations: Bull. Tenn. Exp. Sta. 7: pi. 12, f. 46 (as P. paucifiorum); Bull. U. S. Dep. Agr. 

 Agrost. 17: /. 392; Contr. U. S. Nat. Herb, 15: /. 319; Francis, Book Grasses 72; Britt. & Brown, 

 111. Fl./. 259; ed.2.f.372. 



Panicum 



256. 1824. 



Panicum paucifiorum HHi Bot. S. C. & Ga. 1: 120. 1816. Not P. paucifiorum R. Br. 1810. 

 Panicum scoparium angustifolium Vasey, Bull. U. S. Dep. Agr. Bot. 8: 32'. 1889. 

 Panicum scoparium paucifiorum Scribn. Bull. Tenn. Kxp. Sta. 7: 48. 1894. 



Vernal phase olivaceous, in loose tufts of few to several culms 35-80 cm. high, erect, often 

 purplish, appressed-pubescent, especially below; leaf -sheaths shorter than the internodes or 

 the lower longer, the papillose pubescence ascending; hairs of the ligule 1-2 mm. long, with 

 longer ones intermixed; blades stiffly spreading or ascending, 6-14 cm. long, 5-8 (rarely 10) 



mm. wide, sharply acuminate, narrowed toward the base, glabrous on the upper surface or 

 rarely with a few long hairs, harshly puberulent beneath, stiffly ciliate near the base; panicles 

 finally long-exserted, 6-12 cm. long, about as wide, loosely flowered, the branches usually stiffly 

 ascending or spreading; spikelets long-pediceled, 3.5-4 mm. long, 1.7—1.9 mm. wide (smaller in 

 exceptional specimens), oblong-obovate, subacute, sparsely hirsute; first glume less than half 

 the length of the spikelet, acute; second glume slightly shorter than the fruit and sterile lemma;, 

 fruit 2.8-3 mm. long, 1.5-1.6 mm. wide, elliptic. 



Autumnal phase erect or spreading, sometimes topheavy-prostrate, branching sparingly 

 from the lower, freely from the upper, nodes, the short branchlets aggregated late in the season 

 at the summit of the branches, the crowded, reduced blades widely spreading, the panicles 

 more or less included and reduced to a few spikelets, these commonly more turgid and blunt 

 than those of the primary panicle. 



Type locality: Georgia. 



Distribution: New Jersey to Florida and eastern Texas, and northward to northern Indiana. 

 Illustrations: Bull. U. S. Dep. Agr. Agrost. 17: /. 394; Contr. U. S. Nat. Herb. 15: /. 321; 

 Britt. & Brown, 111. Fl. ed. 2./. 373. 



185. Panicum Ravenelii Scribn. & Merr. Bull. U. S. Dep. Agr. Agrost. 



24: 36. 1901. 



Panicum scoparium majus Vasey, Bull. U. S. Dep. Agr. Bot. 8: 32. 1889. 

 Panicum scoparium genuinum Scribn. Bull. Tenn. Exp. Sta. 7: 48. 1894. 



Vernal phase in loose tufts, grayish-olive; culms 30-70 cm. high, erect or ascending, densely 

 papillose-hirsute with ascending hairs, the nodes short-bearded; leaf -sheaths shorter than the 

 long lower internodes, about equaling the short upper ones or overlapping, papillose-hirsute 



