146 WEEDS'OF THE FARM AND GARDEN 



Wahlenb.). A perennial grass with creeping, fragrant 

 rootstocks, one to two feet high ; panicles somewhat one- 

 sided, two to five inches long; spikelets chestnut-colored, 

 three-flowered; the two lower flowers staminate, hairy 

 fringed, with three stamens, the upper flower perfect, 

 short pediceled, awnless and with two stamens. Com- 

 mon in the mountain regions and in the north. Frequent- 

 ly a troublesome weed in Minnesota and Northwest Ter- 

 ritory. 



Western Stipa (Stipa comata, Trin. and Rupr.). Also 

 known as needle grass, a rather stout, erect perennial, 

 growing one and one-half to four feet tall and forming 

 tufts or mats; leaves rolled inward (involute); loosely 

 flowered panicles, eight to twelve inches long; spikelets 

 with nearly equal, long-pointed glumes about twice as 

 long as the thinly pubescent, flowering glume ; awn slen- 

 der, two and one-half to three inches long, strongly bent 

 and twisted; blooming period from May to September. 

 Rather rare in Iowa, few specimens having been reported. 

 Common and abundant in northwest Canada and on the 

 plains west of the Missouri river. 



Needle or Porcupine Grass (Stipa spartea, Trin.). A 

 stout, erect perennial with simple stems three to five feet 

 high ; leaves long and narrow ; plant bears few flowers 

 and these are carried on large, open panicles four to eight 

 inches long; seed long-awned, bearing a sharp-pointed 

 callus with barbs extending upwardly, which enable the 

 seed to bury itself; blooming period from June to August. 

 Common on dry, gravelly soils throughout the northern 

 Mississippi valley states and frequently found in prairie 

 hay; especially injurious to horses, cattle and sheep, pro- 

 ducing severe inflammation and occasionally causing 

 death. 



Poverty Grass (Aristida dichotoma, Michx.). A slender, 

 tufted, branched annual from twelve to twenty-four 

 inches tall ; spikelets in narrow, striate, simple or com- 





