20. Panicum Perlongum Nash. Long-Stalked Panic-Grass

Fig. 330

Panicum perlongum Nash, Bull. Torrey Club 26: 575. 1899.

Culms 8'-16' tall, simple; sheaths hirsute with long ascending hairs; blades elongated, linear, erect, papillose-hispid beneath, 1"-1 1/2" wide, the upper one commonly 3'-5 1/2' long; primary panicle long-stalked, much-exserted, generally extending beyond the apex of the upper leaf, 1 1/2-2 1/2 long, its branches erect or nearly so; spikelets about \Y' long, about 1/2 as wide, glabrous or pubescent with a few scattered long hairs, strongly nerved.

On praries and in dry soil, Michigan to South Dakota, Manitoba and Texas. June-Aug.

21, Panicum Linearifolium Scribn. Low White-Haired Panic-Grass

Fig. 331

Panicum Enslini Nash, in Britt. Man. 83. 1901.

Not Trin. 1826. Panicum linearifolium Scribn.; Nash, in Britt. &

Br. 111. Fl. 3: 500. 1898.

Culms tufted, slender, erect, smooth and glabrous, simple, 6'-16' tall. Sheaths glabrous or pilose with long white hairs, longer than the internodes; ligule a ring of short hairs; blades elongated, smooth or rough, glabrous or more or less pilose, especially upon the lower surface, 3'-10' long, 1"-2" wide, the uppermost leaf the longest and often extending beyond the panicle; primary panicle loose and open, often long-exserted, 1 1/2'-4' long, its branches lax, ascending, secondary panicles small and contracted on very short culms and partly concealed by the bases of the long culms: spikelets 1"- 1 1/4" long, obtuse or acutish, pubescent with spreading hairs.

Dry soil, especially hillsides, Nova Scotia to Michigan, south to Georgia, Arkansas and Texas. May-July.

22. Panicum Werneri Scribn. Werner's Panic-Grass

Fig. 332

Panicum Werneri Scribn.; Nash, in Britt. & Br. 111. Fl. 3: 501. 1898.

Smooth and glabrous, light green. Culms tufted, erect, slender, simple or later sparingly branched, io'-i8' tall; sheaths equalling or shorter than the internodes; ligule a ring of short hairs; blades erect, elongated, linear, acuminate, 2 1/2'-4 1/4' long, 1 1/2"-2 1/2" wide, panicle finally long-exserted, loose and open, 2Y-3Y long, its branches ascending; spikelets about 1" long on longer hispidulous pedicels, oval, minutely and sparsely pubescent, the first scale orbicular, about one-quarter as long as the spikelet, 1-nerved, the second and third scales 7-nerved, the fourth scale oval, slightly apiculate.

Dry knolls in swamps. Maine to Ontario, Ohio, Missouri and Texas. June-July.

23. Panicum Bicknellii Nash. Bicknell's Panic-Grass

Fig. 333

Panicum Bicknellii Nash, Bull. Torrey Club, 24: 193. 1897.

Culms erect or decumbent at the base, slender, 8'-16' tall, at length sparingly branched, the lower internodes puberulent, the nodes sparingly barbed. Sheaths generally longer than the internodes, cili-ate on the margins, the lowermost pubescent; ligule a fringe of very short hairs; blades elongated, increasing in length toward the top of the culm, erect, linear-lanceolate, acuminate, narrowed toward the ciliate base, 7-9-nerved, primary leaves 3'-7' long, 2 1/2"-5" wide; primary panicle 2 1/2-3' long, its branches ascending, secondary panicles smaller, with appressed branches; spikelets obovate or oval, 1 1/4"- 1 1/2" long, pubescent with short spreading hairs, the first scale 1-nerved, the second and third scales 9-nerved.

Dry wooded hills, Connecticut, New York and Pennsylvania to Georgia. July-Aug.