20. Panicum capillare L. Witchgrass. Fig. 163. 



Annual, freely branched from the base; culms usually somewhat spreading from 

 the base, 2-8 dm. long, papillose-hispid to rarely nearly glabrous; sheaths hispid; 

 ligule 1-3 mm. long; blades 10-25 cm. long, 5-15 mm. broad, hispid on both 

 surfaces; panicles many-flowered, diffuse, often making up half the total length 

 of the plant, included at base until maturity, the branches finally divaricately 

 spreading, the whole panicle breaking away and rolling before the wind; spike- 

 lets 2-3.3 mm. long, pointed or attenuate at the tip, 7- to 9-nerved, glabrous; 

 first glume large, clasping; fertile lemma and palea smooth and shining, usually 

 olive-brown at maturity. Incl. var. occidentale Rydb. 



Moist soil in waste and cultivated lands, along irrigation ditches, and in wet 

 sandy places along streams, about playa lakes and low alluvial soils in Okla. 

 (Alfalfa Co.) and in the Tex. Trans-Pecos and Plains Country, infrequent e. to 

 n.-cen. Tex. and N. M. (San Miguel and Sierra cos.), often in disturbed ground, 

 summer-fall; most of N.A. 



21. Panicum dichotomiflorum Michx. Fall panic. Fig. 164. 



Somewhat succulent branching annual; culms ascending or spreading from a 

 geniculate base, 5-10 dm. tall or in robust specimens to 2 m. long; ligule a 

 dense ring of white hairs 1-2 mm. long; blades flat, scaberulous and sometimes 

 sparsely pilose on the upper surface, 1-5 dm. long, 3-20 mm. broad, the white 

 midrib usually prominent; panicles many-flowered, terminal and axillary, mostly 

 included in the upper sheath at the base, 1-4 dm. long or more, the main branches 

 rather stiff, ascending, the branchlets short and appressed along the main branches; 

 spikelets short-pedicelled, narrowly oblong-ovate, 2-3 mm. long, acute, 7-nerved, 

 glabrous; first glume only about a fourth as long as the spikelet; fertile lemma 

 smooth and shining. 



Moist ground along streams and in disturbed soil, marshy areas, in sluggish 

 streams and seepage areas, in Okla. (McCurtain, Nowata, Kay and Pittsburg 

 COS.) and in e. half of Tex., more common in low areas near the coast such as 

 rice fields, rare in e. part of Plains Country, late summer-fall; N.S. and Me. to 

 Minn., s. to Fla. and Tex., occasionally introd. farther w.; W.I. 



53. Sacciolepis Nash 

 A genus of about 30 species in warm regions. 

 1. Sacciolepis striata (L.) Nash. Fig. 165. 



Perennial; culms extensively creeping, the lower internodes 2-4 mm. thick; 

 sheaths usually shortly papillose-pilose; ligule obsolete; blades with conspicuous 

 nervature; panicles terminal, not much-exserted, spiciform, 6-15 (-25) cm. long, 

 about 1 cm. thick, with numerous appressed branches, the minute ultimate pedicels 

 abscising just below the glumes; spikelets not much-compressed, 2-flowered, the 

 lower floret staminiferous, the upper perfect; rachilla abscising just below the 

 fertile lemma; first glume minute, triangular, 3- to 5-nerved; second glume lanceo- 

 late, gibbous basally, 4-5 mm. long, strongly several-nerved; lower lemma as 

 long as the second glume, with obscure nerves and a well-developed palea and 

 3-stamens; fertile lemma about half as long as the spikelet, very thin-cartilaginous, 

 oblong, blunt, the margins revolute, enclosing the palea of the same texture. 



In moist sands near streams, marshes and bogs, in shallow water of lakes and 

 ponds, in Okla. (Johnston Co.) and infrequent to rare in e. and s.e. Tex. (Jasper 

 Marion, Houston, Cherokee and Wood cos.), late summer-fall; Coastal States, 

 N. J. to Tex.; Okla. and Tenn. 



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