Vegetation- Sites occupied by ATRNUT/MONNUT appear barren in 

 spite of moderate cover by the two dominant species. Atriplex 

 nuttallii was present in tv;o of three stands with a mean cover of 

 35%. Sarcobatus vermiculatus and Sueda nigra were both present 

 in one stand, but neither were common. Grass cover is sparse; 

 Hordeum jubatum was present in two stands, and Oryzopsis 

 hymenoides was present in one stand. Monolepis occurred in all 

 stands with a mean cover of 34%. Allium textile , Camissonia 

 scapoidea , Platyschkurhia integrif olia and Opuntia polyacantha 

 are found in most stands, but all have low cover. Lichens and 

 bryophytes are absent or nearly so. 



Soils- ATRNUT/MONNUT occurs on deep, heavy clay soils with 

 extremely low infiltration rates. Parent materials are shale, 

 clay, or bentonite. Gravel derived from old streambeds or shores 

 is often present on the surface as are salt deposits. We 

 collected no additional soils data for this type. 



Other Studies- This community type has not been previously 

 described. It would probably fit into Knight et al.'s (1987) 

 saltbush desert shrubland. These authors do not mention the 

 presence of Monolepis nuttalliana , but this species is an annual 

 and may not always be as prevalent as it was in 1991. This 

 community type is probably similar to the Atriplex 

 nuttallii / Allenrolf ea occidentalis type described for Idaho, 

 Wyoming and Utah (Bourgeron and Engelking 1992). 



Natural Heritage Program Rank- G2?/S2? 



28. Potentilla f ruticosa / Festuca idahoensis c.t. 



(POTFRU/FESIDA; shrubby cinquef oil/Idaho fescue) 



(1 stand) 



Environment- POTFRU/FESIDA is a minor type found near lower 

 timberline on cool slopes in the Pryor Mountains. The elevation 

 of our one stand was 7,080 feet Adjacent communities are 

 dominated by Abies lasiocarpa and Pseudotsuga menziesii . 



Vegetation- Potentilla f ruticosa is the only common shrub; it had 

 20% canopy cover in the one stand sampled. Festuca idahoensis is 

 the most abundant grass, but Koeleria pyramidata , Leucopoa kingii 

 and Agropyron caninum are also common. Forbs are common and 

 conspicuous. Solidago missouriensis . Anemone patens , Galium 

 boreale and Astragalus miser are common species, Bryophytes and 

 lichens are uncommon. 



Soils- POTFRU/FESIDA occurs on deep soils derived from limestone. 

 Surface texture is silty or loamy and gravel is rare. VJe 

 collected no additional soils data for this type. 



30 



