92 POACEAE 



wide, linear: panicle G-14 cm. long, its branches very long, naked below, erect to widely 

 spreading : spikelets at the end of the branches, 3-4 mm. long and 1.5-1.8 ram. wide, 

 elliptic, acute, densely papillose-hii-sute with ascending hairs. [P. sparsiflorum Vasey.] 

 In wet soil, the Indian Territory to Mississippi and Texas. Fall. 



15. Panicum capillare L. Stems 3-6 dm. tall, simple, or branched near the base, 

 stout: leaf-sheaths usually purplish, papillose-hirsute; blades 1.5-8 dm. long, 6-16 mm. 

 wide, pubescent: primary jjanicle 2-3.5 dm. long, the larger branches 1.5-2.5 dm. long, 

 the lateral panicles smaller : spikelets very numerous, 2-2.5 mm. long, lanceolate, acumi- 

 nate, glabrous. 



In dry soil, and common in cultivated ground as a weed, Nova Scotia to Minnesota, Florida and 

 Texas. Summer and fall. Witch Grass. Tumble Weed. 



16. Panicum Philadelphicum Bernh. Stems erect, 2-6 dm. tall, slender, somewhat 

 branched at the base: leaf-sheaths hirsute; blades 5-10 cm. long, 2-6 mm. wide, erect, 

 pubescent : panicle 10-23 cm. long, its lower branches spreading or ascending : spikelets 

 about 1.5 mm. long, elliptic, acute, glabrous. 



In dry woods and thickets. New Brunswick to Georgia and Missouri. Summer and fall. 



17. Panicum Gattingeri Nash. Annual. Stems commonly slender, finally branched 

 and often prostrate at the base, 3-6 dm. long : leaf-sheaths papillose-hirsute ; blades 1.5 

 dm. long or less, 4-8 mm. wide, pubescent, erect: primary panicle 1-1.5 dm. long, its 

 branches ascending, the larger ones usually 5-7 cm. long, the lateral panicles smaller : 

 spikelets about 2 mm. long, elliptic, acute, glabrous. 



In poor soil, Connecticut and New Jersey to North Carolina and Tennessee ; also in Missouri. Fall. 



18. Panicum flexile (Gattinger) Scribn. Stems erect, 1.5-4.5 dm. tall, slender : 

 leaf-sheaths papillose-hirsute ; blades 10-23 cm. long, 4-6 ram. wide, erect, long-acumi- 

 nate, pubescent : panicle 1-2.5 dm. long : spikelets about 3 mra. long, much shorter than 

 the pedicels, acuminate, glabrous. 



In moist or dry soil, Pennsj'lvania to Tennessee and Missouri. Summer and fall. 



19. Panicum proliferum Lam. Stems at first erect, 3-6 dm. tall, simple, later de- 

 cumbent, 1-1.5 m. long, l)ranched at all the upper nodes : leaf-sheaths loose, glabrous, 

 somewhat flattened ; blades 1.5-6 dm. long, 4-20 mm. wide, long-acuminate : panicle 

 pyramidal, 1-4 dm. long: spikelets 2-3 ram. long, lanceolate, acute, glabrous. 



In wet soil, Maine to Pennsylvania, Nebraska, Florida and Texas. Summer and fall. 



20. Panicum miliaceum L. Stems erect or decumbent, rather stout, 3 dm. tall or 

 more : leaf-sheaths jiapillose-hirsute ; blades 1-2.5 dm. long, 8-25 mni. wide, pubescent : 

 panicle rather dense, 1-2.5 dm. long, its branches erect or ascending : spikelets 5 mm. long, 

 acuminate, glabrous. 



In waste places, Maine to Delaware, Pennsylvania, and Georgia, and in Nebraska. Introduced 

 from the Old World. Summer and fall. Millet. 



21. Panicum atenodes Griseb. Glabroiis, or the lower leaf-sheaths sometimes 

 pul^escent. Stems tufted, wiry, erect, 3-8 dm. tall, finally branched : leaf-blades erect, 

 involute when dry, 1.5 dm. long or less, 1-1.5 mm. wide : panicle narrow, 3-15 cm. long, 

 its branches erect, the pedicels often with a few bristles at the base : spikelets about 2.5 

 mm. long, lanceolate, acute, glabrous. 



In moist and sandy pine lands, Florida to Texas. Also in the West Indies. Spring to fall. 



22. Panicum diffiisum Sw. Glabrous. Stems tufted, erect, 2-4 dm. tall, rather 

 slender: leaf-blades linear, narrowed toward the base, long-acuminate, 2.5 dm. long or 

 less, 3-4 mm. wide, erect : panicle 8-15 cm. long, its branches ascending : spikelets gla- 

 brous, lanceolate, acute, about 2 mm. long. 



In sandy soil, southern Texas and Mexico. Spring to fall. 



23. Panicum Hallii Vasey. Stems tufted, branching from the base, glabrous : leaf- 

 sheaths glabrous ; blades erect, linear, long-acuminate, 5-15 cm. long, 2-4 mm. wide, gla- 

 brous: panicle 1-2 dm. long, its branches long and ascending: spikelets about 2.5 ram. 

 long, ovoid, acute, glabrous. 



In dry soil, Texas. Spring and summer. 



24. Panicum filipes Scribn. Glabrous. Stems erect, 8-10 dm. tall : leaf-blades 

 linear, long-acuminate, lighter above, 3-4 dm. long, 5-8 mm. wide : panicle 1.5-2.5 dm. 

 long, efTuse, its slender branches spreading : spikelets glabrous, ovate-lanceolate, about 

 2.5 mm. long, acute, the first scale large and acute, a little more than i as long as the 

 spikelet. 



In dry soil, southern Texas. Spring and summer. 



25. Panicum cognatum Schult. Stems tufted, 3-6 dm. long, at first erect, finally 

 prostrate and branched at the Ijase, glabrous : leaf-slieaths usually longer than the inter- 

 nodes, glabrous, or more or less pubescent with very long weak hairs ; blades erect, linear 



