Soils: ARTTSV/FESIDA occupies vast acreages of the Sebud-Hapgood complex, the dominant 

 soil mapping unit of the southern part of the study area (USDA Soil Conservation Service 1989). 

 These are deep, well drained Cryoborolls of colluvium parent material derived from metamorphic 

 basement rocks, mostly gneiss and schists. 



Vegetation: Artemisia tridentata ssp. vasyana is the only well represented slirub in the plots with 

 about 30% cover and Festuca idahoensis is the only well represented grass with about 40% 

 cover. The bunchgrass Agropyron spicatum (syn. Elymus spicatus, Pseudoregneria spicatum) is 

 present in small amounts in both plots. The forb component is relatively diverse and varies 

 between the plots but cover by individual species is relatively low. Lupinus sericeus is the only 

 forb abundant in both plots. Other forbs which are constant in the plots are Achillea millefolium, 

 Antennaria microphylla, Castillejaflara, Cerastium arvense, Erigeron composilus, Geum 

 triflorum. Mertemia oblongifolia, and Phlox longifolia. The Geranium viscosissimum phase of 

 ATRTSV/FESIDA, which is indicated by high cover and diversity of forbs, occurs at more mesic 

 sites with deeper soils, higher elevations, or cooler aspects. Artemisia tridentata is killed by fire, 

 and burning results in higher cover by the bunchgrasses Festuca idahoensis and Agropyron 

 spicatum (also see the description of FESIDA/AGRSPI in this report). 



Comments: In the Ruby Range this type has a long history of grazing by livestock and is 

 important big game habitat. Variation in slope results in differential use by cattle resulting in 

 overgrazing of more level sites. The relatively high cover by sagebrush for the type found in the 

 study area plots may be due to grazing pressures and/or fire suppression. Control of wildfires and 

 a long history of cattle grazing in the Ruby Range have probably increased aerial and temporal 

 coverage by ARTTSV/FESIDA with a corresponding decrease in Festuca idahoensis/Agropyron 

 spicatum. This has probably resulted in a decrease in productivity of forage for big game and 

 cattle. 



Artemisia tridentata ssp. tridentata/Agropyron smitliii community type 



(ARTTST/AGRSMI: basin big sagebrush/western wheatgrass; WHTF designation 



Artemisia tridentata ssp. tridentata/Pascopyrum smithii; 



MTNHP rank G2G3/SU undetermined; 1 plot ) 



Environment: ARTTST/AGRSMI was sampled once in the drainage of Spring Creek in the 

 eastern foothills of the Ruby Range and is a minor type confined to alluvial benches of creek and 

 canyon bottoms. The sampled plot was on a gentle slope with east aspect at 6,120 feet elevation 

 just above a developed spring. Drier upland slopes in the vicinity have Artemisia tridentata ssp. 

 vaseyana and Juniperus scopulorum communities. Wliere it was seen in canyon bottoms, 

 adjacent canyon slopes have Cercocarpus ledifolius and Pseudotsuga menziesii community types. 



Soils: The plot is within the Musselshell-Amesha, bedrock substratum complex soil mapping unit 

 (USDA Soil Conservation Service 1989). The Musselshell series is found in drainageways within 

 the unit and probably represents the soils of the community type. They are classified as 

 Calciorthids and are deep well-drained calcareous loams formed in alluvial and eolian materials 

 derived mostly fi-om limestone. 



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