1 32 POACEAE 



45. Trisetum Pers. 



Flowering scales all bearing long dorsal awns. I. T. spicatum. 



Lower flowering scale not bearing a long dorsal awn, a rudiment 



sometimes present. 2. T. pennsylvanicum. 



1. T. spicatum (L.) Richter. In rocky places: Lab. to Alask., 



south on the mountains to N. Car., N. Mex. and Cal. Also 



in Eu. and Asia. 



Conn. Limestone ridges, Salisbury; rare. 



N. Y. Montgomery, Orange Co., rare. 



Predominating on limestone, but very rare in our area. 



2. T. pennsylvanicum (L.) Beauv. {Spenopholis pahistris (Michx.) 



Scribn.). In swamps and wet meadows: Mass. to 111., south 

 to Fla. and La. 



Throughout the range, except the pine-barrens, there not re- 

 corded; rare on L. I. 

 T. flavescens (Lt) R. & S. has been found at Bedford, Westchester Co , N. Y., pre- 

 sumably as a waif. 



46. Avena [Tourn.] L. 



I . A. sativa L. Persisting as a weed along roadsides and in fields. 

 Native of Europe. 

 Not uncommon as a sporadic escape. 

 Avena pubescens Hudson and A. sterilis L. both of Europe are reported as waifs 

 from N. J. 



47. Arrhenatherum Beauv. 



1. A. elatius (L.) Beauv. In fields and waste places: Newf. to 

 Ont. and Minn., Ga., Tenn. and La. Native of Europe. 

 Common throughout the range as a weed. 



48. Danthonia DC. 



Spikelets, exclusive of the awns, less than 12 mm. long. 



Teeth of the flowering scales merely acute, not awned. I. D. spicata. 



Teeth of the flowering scales long awned. 2. D. compressa. 

 Spikelets, exclusive of the awns, exceeding 12 mm. long. 



Foliage and flowering scales pubescent. 3. D. sericea. 



Foliage glabrous; flowering scales partly ciliate. 4. D. epMs. 



i. D. spicata (L.) Beauv. In dry soil: Newf. to S. Dak., south 

 to N. Car. and Tex. 

 Throughout the range, rare in the pine-barrens. 



