April I, 1916 363 



Elf,u.sink Gaertn. Yard grass. 



Ei,KUSiNK INDICA Giertn. i. Yard o[iass. Yards, railroad 

 tracks and waste places, Aibir.a and I{ast Porllaiid. Naturalized 

 from tropical Europe and Asia. June to September. 



X ElEUSINK CORACANA Pers. I. Tall yard grass. Ballast 

 ground and waste places, Lower Albina; coarse annual, taller 

 than E. indica. Naturalized from tropical Europe and Asia. 

 June to September. 



Pentameris Beau v. Wild oat grass. 

 PenTAMERIS californica (Boland.) Nels. & Macb. 4, 

 Western wild oat grass. [Dauthom'a cali/omica.) In fields and 

 waste places near Oswego. May to July. 



Avena [Tourn.] L. True oats. 

 AVENA FATUA L. 1. Wild oats. Common in fields and waste 

 places around Portland. Naturalized from Europe. June to Aug. 



Avena fatua gIvABRATa Peterm. r. Smooth wild oats. 

 A common, more or less troublesome weed in fields, roadsides 

 and waste places around Portland. Naturalized from Europe. 

 June to August. 



Trisetum Pers. False oat. 



Trisetum canescens Buckley. ^. Hoaiy false oat. Occurs 

 sparingly on rocky slopes about Elk Rock and along the Wil- 

 lamette river near Oswego. May to August. 



Trisetum spicatum (L.) Richter. 4. {T. subspicatum.) 

 Nanow false oat. Along railroad tracks and in waste places, 

 Lower Albina. Unnoubtedly introduced here from eastern Ore- 

 gon or W'ashington. June to September. 



Aira L. Hair grass, 

 AiRA caryophyllea L. I. Silvery hair grass. Delicate, sil- 

 very annual, in fields, vacar^t lots and waste places around Port- 

 land. Naturalized from Europe June to August. 



Deschampsia Beauv. Stout hair grass; tickle grass. 

 Deschampsia caespitcsa (L.) Beauv. 4. Tufted hair grass. 

 Ppen glades and wet ground along Columbia slough. June, July. 



