Comments: DeVelice et al. (1995) described an ATRGAR / perennial grass community type from 

 northeastern Montana, which they tentatively split into three community types with differing 

 dominant grasses, Pascopyrum smithii (syn. Agropyron smithii), Pseudoroegneria spicata (syn. 

 Agropyron spicatum), and Sporobolus airoides. These communities differ from our plots by having 

 higher grass cover and by occurring in badland settings. Other Atriplex gardneri-domimiQd 

 community types described in the state include A. gardneri / Oryzopsis hymenoides from 

 southwestern Montana (Cooper et al. 1995), A. gardneri / Moonless nuttallii in the Prior Mountains 

 vicinity of south-central Montana (DeVelice and Lusaka 1993), A.gardneri/Pascopyrum smithii from 

 north-central Montana (Heidel and Cooper 1996) ondA. gardneri / Eriogonum pauciflorum from 

 northeastern Montana (DeVelice et al. 1995). Eriogonum pauciflorum is abundant in Carter County 

 and forms communities also associated with shale ridge systems, although it more consistently 

 occurs on lower slope and outwash flat positions; it is ostensibly associated with acidic substrates. 

 In Carter County and contrary to the observations of DeVelice et al. (1995) for northeastern 

 Montana, E. pauciflorum and Atriplex gardneri were never observed to codominate and seldom do 

 their distributions even overlap. Branson et al. (1970) described both upland and lowland Atriplex 

 gardneri communities in northeastern Montana. Atriplex gardneri communities in Montana appear 

 to display distinct local variation, which defies lumping into a single plant association, but we are 

 not prepared to recognize each species association as a discrete community without more 

 information. 



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