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



Texas ; Oregon (Linnton) ; throughout 

 tropical America at low altitudes. 

 Commonly cultivated in tropical 

 America as a forage grass, being cut 

 for green feed. It probably was intro- 

 duced into Brazil at an early date 

 from Africa. 



Figure 1026. — Panicum paludivagum. Two views of 

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



3. Fasciculata. — Branching annuals; 

 blades flat ; ligules not more than 

 1 mm. long; panicles of ascend- 

 ing spikelike racemes along an 

 angled axis; spikelets subsessile, 

 abruptly pointed, strongly 5- to 

 7-nerved; fruit transversely ru- 

 gose. 



119. Panicum reptans L. (Fig. 

 1028.) Culms ascending 10 to 30 

 cm. above the creeping base; blades 

 1.5 to 6 cm. long, 4 to 12 mm. wide, 

 cordate, usually glabrous, ciliate on 

 the undulate margin at base; panicle 

 2 to 6 cm. long, the 3 to 12 ascending 

 or spreading racemes 2 to 3 cm. long, 

 aggregate, the rachis usually pilose 

 with long weak hairs; spikelets se- 

 cund, about 2 mm. long, glabrous, on 

 pubescent or pilose pedicels about 1 

 mm. ; first glume very short, truncate 

 or rounded. O — Moist open 

 ground, or a weed in cultivated fields, 

 Florida to Texas; tropical regions of 

 both hemispheres. 



120. Panicum fasciculatum Swartz. 

 Brow t ntop panicum. (Fig. 1029.) 

 Culms erect or spreading from a 

 decumbent base, 30 to 100 cm. tall, 

 sometimes pubescent below the pan- 

 icle or hispid below the appressed- 

 pubescent nodes, the more robust 

 freely branched from the lower nodes ; 

 sheaths glabrous to papillose-hispid; 



blades 4 to 30 cm. long, 6 to 20 mm. 

 wide, glabrous; panicle 5 to 15 cm. 

 long; the racemes 5 to 10 cm. long; 

 spikelets yellow or bronze brown, 2.1 

 to 2.5 mm. long, rarely 3 mm., 

 obovate, turgid, glabrous, strongly 

 transversely wrinkled or veined. O 

 — Moist open ground, often a weed 

 in fields, southern Florida, southern 

 Texas; tropical America, at low alti- 

 tudes. 



Panicum fasciculatum var. re- 

 ticulatum (Torr.) Beal. Differing 

 from P. fasciculatum in having small- 

 er more compact panicles, narrower 

 pubescent blades, less regular sub- 

 erect racemes and larger, mostly more 

 yellowish spikelets 2.6 to 3 mm. long. 

 Many intergrades occur. O (This 

 has been erroneously referred to P. 

 fasciculatum var. chartaginense 

 (Swartz) Doell.) — Prairies, fields, and 

 waste ground; New Mexico and 

 Arizona; Mexico. 



121. Panicum adspersum Trin. 

 (Fig. 1030.) Culms ascending or 

 spreading from a decumbent base, 

 rooting at the lower nodes, 30 to 100 

 cm. tall; blades 5 to 15 cm. long, 8 

 to 20 mm. wide; panicle 6 to 15 cm. 

 long, the racemes 3 to 10 cm. long; 

 spikelets 3.2 to 4 mm. long, fusiform, 

 abruptly acuminate, hispid or his- 

 pidulous, sometimes only at the 

 summit, rarely glabrous, obscurely 

 reticulate-veined. — Moist open 

 ground, often on coral limestone, 

 Florida; ballast, Philadelphia and 

 Camden; Mobile; West Indies. The 

 Florida specimens, commonly more 

 robust than the typical form from the 

 West Indies, have been described as 

 P. keyense Mez. 



122. Panicum ramdsum L. Brown- 

 top millet. (Fig. 1031.) Resembling 

 P. fasciculatum var. reticulatum; ped- 

 icels bristly; spikelets glabrous to 

 finely pubescent, about 3 mm. long, 

 tawny or dull brown. O — Waste 

 ground, North Carolina to Florida, 

 Arkansas, and Louisiana; tropical 

 Asia. Cultivated for bird food. 



123. Panicum arizonicum Scribn. 

 and Merr. Arizona panicum. (Fig. 



