Juniperus scopuloruni/Aitemisia nova community type 



(JUNSCO/ARTNOV; Rocky Mountain juniper/black sagebrush; MTNHP rank G5/S2; 1 plot) 



Environment: JUNSCO/ARTNOV was sampled by only one plot on a fan of dissected, 

 calcareous alluvium in the arid southeastern foothills of the Ruby Range above Spring Creek; the 

 slope was east-facing at 5,800 feet elevation. This is the first time the type has been documented 

 in southwestern Montana and it has been documented by just one other plot in the state, located 

 on calcareous parent materials in the Pryor Mountains of southeastern Montana (DeVelice and 

 Lesica 1993). Slopes across the creek drainage with western aspects support a Juniperus 

 scopulorum/Agropyron spicatum community without Artemisia nova. The heavily grazed stream 

 terrace below supports a highly degraded Artemisia tridentata ssp. tridentata/Agropyron smithii 

 community. 



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

 (USDA Soil Conservation Service 1989). The Amesha series is found on upper slopes and 

 hilltops within the unit and probably represents the soils of the community type. They are 

 classified as Calciorthids and are deep well-drained calcareous soils formed in alluvium derived 

 from soft loamy sedimentary beds. Soils of the Pryor Mountains JUNSCO/ARTNOV stand are 

 also calcareous (DeVelice and Lesica 1993). 



Vegetation: The plot has less than 20% cover by scattered Juniperus scopulonim. The low 

 growing sagebrush Artemisia nova is the only well represented shrub with less than 20% cover. 

 The grass component is dominated by Agropyron spicatum (syn. Elymus spicatus, 

 Pseudoregneria spicatum) with about 30% cover, and Stipa viridis and Poa secunda (syn. P. 

 sandbergii) are also common. There is a high diversity of forbs (29 species) with Hedysarum 

 boreale being the most common species. 



Comments: This is apparently one of the rarer community types in both the study area and 

 statewide (S2) and is cuixently afforded no degree of protection; on a global scale it is rated only 

 G5 because of vast and secure expanses on calcareous mountain ranges (pediments and bajadas 

 *^hereof) of eastern Nevada (Blackburn et al. 1968). It is also significant for hosting a high 

 diversity of forbs in an arid environment. JUNSCO/ARTNOV should be placed on the state 

 BLM Watch List. The community is impacted only lightly by cattle, despite its location in a 

 heavily impacted drainage, probably due to its aridity, steep slopes, and availability of other 

 forage. 



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