capacity is low due to the coarse soil textures, abundant 

 coarse fragments, and shallow depth. 



Adjacent Communities. — The Cercocarpus ledif ol ius/Aqropvron 

 spicatum and Juniperus scopulorum/C. ledifolius types are 

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

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

 tions. The Artemisia arbuscula/Agropyron spicatum and Pinus 

 f lexilus/A. spicatum types are sometimes found on adjacent 

 less rocky sites with deeper soils. 



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

 Mueggler and Stewart (1980). 



13. Cercocarpus ledifolius/Festuca idahoensis Type 

 (CERLED/FESIDA; mountain mahogany/Idaho fescue; G2? S2?) 



Vegetation. -- Cercocarpus ledifolius and Agropvron spicatum are 

 abundant. Festuca idahoensis cover generally exceeds 5%. 

 Other species that are generally present with cover exceeding 

 1% include Artemisia f rigida , A. tridentata , Opuntia poly- 

 acantha . and Poa sandbergii . Bromus tectorum may be abundant. 



Physical Setting. --The type occurs on steep residual mountain 

 slopes at elevations around 6000 feet. The total cover of 

 soil, gravel, and rock usually exceeds 40% and the soil sur- 

 face is stable with no evidence of accelerated erosion. 



Parent materials are granitic and soils are Ustorthents 

 and are moderately deep and very cobbly. Textures vary from 

 loamy sands to sandy loams. The soils are non-calcareous and 

 their available water holding capacities are low due to the 

 coarse soil textures and abundant coarse fragments. 



Adjacent Communities. — The Cercocarpus ledifolius/Festuca 

 idahoensis and C_^ ledifolius/Agropyron spicatum types are 

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

 ledifolius/A. spicatum occurs in slightly more xeric situa- 

 tions. The Pseudotsuqa menziesii/F. idahoensis type may be 

 found on adjacent more mesic sites that are less rocky and 

 have deeper soils. 



Other Studies. — This type has not been previously described. 



14. Aqropyron dasystachyum/Phacelia hastata Type 

 (AGRDAS/PHAHAS; thickspike wheatgrass/silverleaf Phacelia ; G2? 

 S2?) 



Vegetation. -- Aqropyron dasystachyum is well represented to 

 abundant within this community type. Other species that are 



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