Physical Setting. — The type predominantly occurs on steep dip 

 slopes and residual mountain slopes at elevations between 5500 

 and 6500 feet. The total cover of soil, gravel, and rock 

 usually exceeds 50% and the soil surface is often unstable 

 because of a lack of adequate vegetation cover. 



Parent materials are predominantly quartzite or limestone 

 and soils are generally Orthents and are shallow (lithic) and 

 gravelly to very stony. Textures vary from loamy sands to 

 loams. Most of the soils exhibit strong and/or violent 

 effervescence. Available water holding capacity is mostly low 

 due to the coarse soil textures, abundant coarse fragments, 

 and shallow depth. 



Adjacent Communities. — The Juniperus scopulorum/Cercocarpus 

 ledifolius and C^ ledifolius/Agropyron spicatum types are 

 ecologically similar and intergrade. Of the two types, J. 

 scopulorum/C. ledifolius occurs in slightly more mesic situa- 

 tions. The J_^ scopulorum/ Artemisia tridentata and A^ triden- 

 tata/Aaropvron spicatum types adjoin sl^ scopulorum/Cercocarpus 

 ledifolius on drier sites. The Aqropvron spicatum/ Bout eloua 

 gracilis type is often found on adjacent less rocky and less 

 steep sites. 



Other Studies. — This type has been described in Montana by 

 Chaffee (1981) . 



Artemisia arbuscul a/ Aqropvron spicatum Type 



(ARTARB/AGRSPI; low sagebrush/bluebunch wheatgrass ; G4G5 S3S4) 



Vegetation. — Artemisia arbuscula and Aqropvron spicatum are 

 abundant within this community type and dominate the shrub and 

 herb layers, respectively. Other species that are generally 

 present with cover exceeding 1% include Artemisia friqida and 

 Chrysothamnus nauseosus . 



Physical Setting. — The type predominantly occurs on steep, 

 rocky slopes at elevations around 7000 feet. The total cover 

 of soil, gravel, and rock usually exceeds 50% and the soil 

 surface is often unstable because of a lack of adequate 

 vegetation cover. 



Soils are generally deep Orthents and are very gravelly 

 and sometimes violently effervescent. Textures are mostly 

 loams. Available water holding capacity is low to medium. 



Adjacent Communities. — The Artemisia arbuscul a/ Aqropvron 

 spicatum and A^ tridentata/ Aqropvron spicatum types are eco- 

 logically similar and often adjoin one another. Of the two 



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