Figure 916. — Panicum Unearifolium. Two views of 

 spikelet, and floret, X 10. (Type.) 



644 MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



to 12 cm. long, lax, few-flowered, the 

 lower branches often reflexed; spike- 

 lets 2.2 to 2.3 mm. long, papillose- 

 pilose. Autumnal blades scarcely re- 

 duced, much exceeding the secondary 

 panicles. % — Rich or damp 

 woods, Virginia to Florida and Ala- 

 bama. 



10. Panicum xalapense H. B. K. 

 (Fig. 919.) Vernal culms and blades 

 on the average shorter than in P. 

 laxiflorum, the blades pilose on one 

 or both surfaces or nearly glabrous, 

 usually short-ciliate ; spikelets 1.9 to 

 2 mm. long, pilose. Autumnal phase 

 with usually denser tufts and shorter 

 blades. 91 — Woods, Maryland to 

 Illinois and Missouri, south to Florida 

 and Texas; Mexico; Guatemala; 

 Dominican Republic. Originally de- 

 scribed from Xalapa (Jalapa), Mexico. 

 Panicum xalapense var. stricti- 

 rameum Hitchc. and Chase. Vernal 



Figure 917. — Panicum werneri. Two views of spike- 

 let, and floret, X 10. (Type.) 



usually sparingly pilose; sheaths gla- 

 brous; spikelets 2.1 to 2.4 mm. long, 

 nearly or quite glabrous. Autumnal 

 phase similar to the vernal, sometimes 

 late in the season bearing simple 

 branches from the lower nodes. Q| 

 — Sterile woods and knolls, Quebec 

 and Maine to Minnesota, Tennessee, 

 Virginia, Kentucky, and Texas. Inter- 

 grades with P. Unearifolium. 



2. Laxiflora. — Tufted, erect to spread- 

 ing; foliage aggregate toward 

 base, light green, soft, the basal 

 blades not in distinct rosettes 

 in autumn; ligule nearly obso- 

 lete; primary panicles long-ex- 

 serted; spikelets obovate, obtuse, 

 turgid, 5- to 7-nerved. Autumnal 

 phase branching near base, form- 

 ing close flat tuft, with reduced 

 panicles. 

 9. Panicum laxiflorum Lam. (Fig. 



918.) Vernal culms 20 to 60 cm. tall, 



erect or geniculate below; nodes 



bearded with reflexed hairs; sheaths 



retrorsely pilose; blades 10 to 20 



cm. long, 7 to 12 mm. wide, gla- ^M^^t*^ foTcuVtgs^s™ 



brous or sparsely cihate; panicle 8 fu.) 



