having modest soil development. It can also occur in badlands, usually on 

 ridgetops or upper slopes where erosion is evident. 



Because of the low number of sample stands for this type, every species 

 encountered in a sample plot found its way into the Constancy and Average 

 Coverage Tables (Appendix A). This makes compositional comparisons difficult. 

 Most Ansc c.t. associates are present. Hedeoma spp. , Astragalus striatus , 

 and Echinacea pallida are often found in this type. Artemisia frigida was 

 encountered in all samples, and the equally ubiquitos Gutierrezia sarothrae 

 and Phlox hoodii were encountered in three out of four samples. 



Agropyron spicatum/Bouteloua gracilis-Carex filifolia Community Type 

 Agsm/Bogr-Cafi c.t.T A. sgicatum is primarily a foothill grassland species 

 in Montana, and it is possible that the A. spicatum in the study area may 

 demonstrate some ecotypic variation. A small percentage of the A. spicatum 

 in the study area is awnless. McMillan (1959, 1969) has substantiated the 

 likelihood of ecotypos in Agropyron spicatum . 



Morris (1971) suggested that in southeastern Montana A. spicatum is 

 found on ridgetops where rocky subsoil and parent material permit better 

 moisture penetration than on well developed soils. Reduced competition on 

 these sites may also be a factor favoring A. spicatum . 



The Agsp/Bogr-Cafi c.t. is usually found on ridgetops and on upper 

 slopes of a cool aspect, and may be associated with a stony substrate. The 

 abundance of B. gracilis and C. filifolia is rather clearly related to 

 grazing, which in turn may be related to topography. C. filifolia may also 

 be associated with soils of limited pedogenic development. 



Chamaephytes such as Artemisia frigida , Eurotia lanata , and Gutierrezia 

 sarothrae are frequently found in the Agsp/Bogr-Cafi c.t. Agropyron dasyta - 

 chyum may be present. 



The Agsp/Bogr-Cafi c.t. seems to be similar to the A. spicatum -C. 

 filifolia -B. a ra c j 1 i s type of Wright and Wright (1948). They suggest that 

 A. spicatum extends into the Great Plains on sandy soils with above average 

 moisture infiltration. The A. spicatum/ B. gracilis habitant type, Liatris 

 punctata phase (Mueggler and Handl 1974) is a similar type found in western 

 Montana. 



Muhlenberqia cuspidata-Agropyron spicatum Community Type (Mucu-Agsp c.t. ) 

 The Mucu-Agsp c.t., a type, is found in sites similar to those of the Agsp/ 

 Bogr-Cafi c.t., but soils are more immature and stony. M. cuspidata is less 

 frequently associated with Andropoqon scoparius , Stipa comata , and even 

 Bouteloua curtipendula . 



In southeastern Montana, Morris (1971) associated M. cuspidata with un- 

 developed soils in grasslands, particularly on dry stony slopes. He noted 

 that M. cuspidata is non-aggressive and is typically found in areas with low 

 ground cover. Coupland (1950) associated M. cuspidata with dry, eroded hill- 

 sides where the A horizon has been lost. 



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