pvramidata occurred in all stands with mean canopy covers of 24%, 

 18% and 29% respectively. Other common graminoids include Carex 

 rupestris , Poa cusickii and P_^ secunda. Forbs are abundant in 

 this community type. Common species include Achillea 

 millefolium , Antennaria microphylla , Arenaria congesta , 

 Astragalus miser , Cerastium arvense and Oxytropis campestris . 

 Arenaria nuttallii , Hymenoxys acaulis , Lupinus argenteus and 

 Phlox hoodii are common in some plots and may indicate 

 overgrazing. Soil lichens are common in most stands. 



Soils- FESIDA-AGRCAN occurs on moderately deep to deep soils 

 derived from Madison limestone. Surface gravel is uncommon or 

 absent but often increases with depth. The soil subgroup at our 

 single soil characterization site was a Calcic Cryoboroll. 

 Carbonates are leached from the surface horizon but also increase 

 with depth. pH of the single stand measured was 6.99, and 

 conductivity was 161 uhmos/cm- (1 stand). 



Other Studies- Mueggler and Stewart (1980) describe a Festuca 

 idahoensis - Agropyron caninum habitat type for southwest Montana. 

 Cooper and Lesica (1992) describe a similar community type from 

 lower portions of the alpine zone for the same region, but their 

 alpine type had many different forbs and graminoids. Similar 

 communities also occur in Wyoming and Colorado (Bourgeron and 

 Engelking 1992) . 



Natural Heritage Program Rank- G4/S4 



33. Carex rupestris / Potent ilia ovina c.t. 



(CARRUP/POTOVI; curly sedge/sheep cinquefoil) 



(1 stand) 



Environment- This minor type occurs on high windswept ridgetops 

 along the crest of the Pryor Mountains. Our one stand was at 

 8,750 feet Adjacent sites with deeper soils support the FESIDA- 

 AGRCAN community type. 



Vegetation- Shrubs are absent. Carex rupestris , Koeleria 

 pyramidata and Calamagrostis purpurascens are the dominant 

 grasses. In our single sample they had 30%, 20% and 10% canopy 

 cover respectively. Oxytropis campestris , Zigadenus elegans and 

 Arenaria obtusiloba are common forbs. Both lichens and mosses 

 are common. 



Soils- CARRUP/POTOVI occurs on shallow, limestone-derived soils. 

 Surface texture is sandy to silty, and gravel is abundant. We 

 collected no additional soils data for this type. 



34 



