46. Panicum Leucothrix Nash. Roughish Panic-Grass

Fig. 356

P. leucothrix Nash, Bull. Torr. Club, 24: 41. 1897.

Culms 1°-2° tall, densely tufted, erect, appressed papillose-hirsute, finally branched; sheaths similarly pubescent but the hairs more spreading; ligule 1 1/2" long; blades 1'-2' long, 2"-3' wide, lanceolate, erect or ascending, firm, softly pubescent on the lower surface, ciliate at the base, glabrous on the upper surface; primary panicle 1'-2' long, rarely larger or smaller, broadly ovate, its branches ascending; spikelets a little over 1/2" long and about 1/2 as wide, oval, pubescent with short-spreading hairs.

In usually dry sandy soil, southern New Jersey to Florida and Texas. Cuba. June and July.

Panicum Wrightianum Scribn., of the southern states and Cuba, which differs in still smaller spikelets, is recorded from southern New Jersey.

47. Panicum Huachucae Ashe. Hairy Panic-Grass

Fig. 357

P. pitbescens Nash, in Britt. & Br. 111. Fl. 1: 121. 1896.

Not Lam. 1797. P. huachucae Ashe, Journ. E. Mitch. Sci. Soc. 15: 51. 1898. P. huachucae silvicola Hitchc. & Chase, Rhodora, 10: 64.

1908.

Culms at first erect and simple, later profusely branched and leaning or ascending, papillose-hirsute with ascending hairs, the nodes barbed; sheaths papillose-hirsute; ligule 1/2"-2" long; blades copiously pilose on the upper surface, densely pubescent on the lower, erect to spreading, firm or lax, those of the culm 2'-3' long, those of the branches much shorter; primary panicle 1 1/2'-4' long, ovoid, the branches ascending or spreading; lateral panicles much smaller, not exceeding the leaves; spikelets about 3/4" long, pubescent.

In dry soil, Maine to South Dakota, Florida, Texas and California. June-Sept. Has been mistaken for P. unci-phyllum Trin.

48. Panicum Scoparioides Ashe. Stiff Hairy Panic-Grass

Fig. 358

Panicum scoparioides Ashe, Journ. E. Mitch. Sci. Soc. 15: 53. 1898.

Culms 1°-2 1/2° tall, rather slender, pubescent with ascending hairs, finally branched; sheaths strongly papillose-hispid with ascending hairs; ligule i"-i 1/2" long; blades 2'-4' long, 2 1/2"-4" wide, lanceolate, ascending, glabrous on the upper surface, the lower surface more or less pubescent with scattered spreading hairs; panicle barely exserted, 2'-3 long, its branches ascending; spikelets a little less than 1 1/4" long and about 1/2 as wide, elliptic, pubescent.

In dry soil, Vermont to Pennsylvania, Delaware and Minnesota. July and August.

Panicum languidum Hitch. & Chase, of Maine, Massachusetts and New York, differs from this and related species by its pointed spikelets.

49. Panicum Villosissimum Nash. White-Haired Panic-Grass

Fig. 359

P. villosissimum Nash. Bull. Torr. Club, 23: 149. 1896. P. atlatiticum Nash, Bull. Torr. Club, 24: 346. 1897.

Papillose-pilose with long white spreading hairs.

Culms tufted, at length branched, 12'-20' tall, erect or ascending, a smooth ring below the nodes which are barbed with spreading hairs; sheaths shorter than the internodes; ligule a ring of hairs 1"-2 1/2" long; blades erect or ascending, rigid, thickish, lanceolate, 1 1/4'-4' long, 2"-3 1/2" wide, acuminate, middle leaves the longest; panicle 1 1/2'-3' long, 1 1/4'-2 3/4' wide, the branches and their divisions hispidulous; spikelets numerous, obovate to elliptic, about 1 1/4" long, 3/4" wide, densely pubescent with short spreading hairs.

Dry soil, Massachusetts to Minnesota, Florida, Texas and Missouri. June-Aug.

Panicum pseudopubescens Nash, differs in nearly ap-pressed pubescence of the culms and glabrous upper leaf-surfaces. It ranges from Connecticut to Illinois, Florida and Mississippi.