38 



WEED FLORA OF IOWA 



Pig. 20-A. Distribution of Sheathed Rush Grass. 



Distribution.— Common in sterile fields and waste places from 

 New England to Wisconsin, South Dakota, and Iowa, and south- 

 ward. Especially common in pasitures, lawns, and along roadsides 

 in Iowa. Story, Polk, Boone, Clinton, Crawford, Carroll, Web- 

 ster and Emmet counties. 



Extermination. — This annual is easily exterminated by culti- 

 vation. The small fibrous roots succumb readily when exposed to 

 the sun. Do not permit the plant to form seed. 



Small Rush Gra,ss {Sporobolus neglectus Nash). 



Descriptinn. — Culms 6-12 in. high, erect, from a usually decum- 

 bent base, slender, often much-branched, smooth and glabrous; 

 sheaths about half as long as the internodes, inflated; ligule very 

 short ; leaves 1 line wide or less at the base, smooth and glabrous be- 

 neath, scabrous and hairy near the base above, attenuate into a 

 slender point, the lower elongated, the upper 1-3 in. long, setaceous ; 

 terminal panicle 1-2% in. in length, usually more or less included in 

 the upper sheath, striate; lateral panicles enclosed in the sheaths; 

 spikelets about 11/2 lines long, the outer scales acute, the lower one 

 slightly shorter, third scale acute, glabrous, a little longer than the 

 second, and about equaling the acute palet. 



Distribution. — Occurs from New Brunswick to Virginia, Wiscon- 

 sin, Iowa, South Dakota and Texas. In similar situations with the 

 preceding species. Along beaten paths, pastures and roadsides. 



