116 



HORDEAE 



Elymus 



Map 179 



Elymus villosus Muhl. 



Blades villous above, smooth or scabrous beneath; paleas 5.5-7 mm long; grain 

 4-4.5 mm long. 



Lemmas and glumes hirsute 3. E. villosus. 



Lemmas and glumes glabrous or sparingly strigose-hispid 



3a. E. villosus f . arkansanus. 



Glumes mostly 1.3-2.5 mm wide (rarely as narrow as 1 mm), generally conspicuously 

 curved outward and indurated at the base, usually more or less dilated above 

 and twisted, generally plainly 5-nerved on the upper half (sometimes 3- or 

 4-nerved), the basal part generally rounded and nerveless. 

 Spikes included at the base or barely exserted. 

 Spikelets with awns more than 3 mm long. 



Glumes and lemmas glabrous or scabrous on the margins only; upper surface 



of leaves usually scabrous (rarely pubescent) 4. E. virginicus. 



Glumes and lemmas hirsute ; upper surface of leaves glabrous 



4a. E. virginicus var. intermedins. 



Spikelets awnless or some with awns up to 3 mm long 



4b. E. virginicus var. submuticus. 



Spikes generally long-exserted. 



Glumes and lemmas hirsute; upper surface of leaves villous 



4c. E. virginicus var. australis. 



Glumes and lemmas glabrous or strigose-scabrous. 



Blades glabrous above; awns generally 5-15 mm long 



4d. E. virginicus var. jejunus. 



Blades hirsute above ; awns generally 15-30 mm long 



4e. E. virginicus var. glabriflorus. 



1. Elymus canadensis L. Canada Wild-rye. Map 177. Infrequent to 

 locally common in sandy soil along roadsides and railroads, in open wood- 

 land, on open dunes, and in prairie habitats. It becomes very local south 

 of the lake area and probably is absent from some of the southern counties. 

 It is extremely variable in the size of the spikes and in the density of 

 the pubescence of the spikelets. 



Que. to s. Alaska, southw. to Ky., Mo., Tex., and Ariz. 



2. Elymus riparius Wieg. (Rhodora 20: 84-86. 1918.) Map 178. This 

 is a recently described species and is infrequent probably throughout the 



