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HABITAT: The rolling foothills setting is on granular, diabase-derived sediment with vegetation 

 dominated by Artemisia tridentata/Agropyron spicatum. It is consistent with all available information 

 on the Ravalli County collection site in being dry, rocky, and east-facing. The area where Erigeron 

 linearis is present corresponds with a gap in Artemisia tridentata dominated by Agropyron smithii. The 

 Vi ha opening in sage cover is traversed by a faint 2-track leading to an old mining test dig nearby. 

 There is no apparent break in the physical environment. Other native species that are common on the 

 adjoining hillside are absent in the small opening, while disturbance-favored species are locally 

 common. The population site may have been grubbed or accidentally burned such that the sage was 

 killed. Otherwise, a highly restricted microhabitat condition such as a claypan could be present apart 

 from disturbance. Associated species include: 



Agropyron smithii 

 Arenaria kingii 

 Bromus tectorum 

 Chysopsis villosa 

 Haplopappus acaidis 

 Oxytropis sericea 

 Phlox biyoides 



POPULATION INFORMATION: The population consisted of ca. 50 individuals. Most were multi- 

 stemmed and vigorous. 



MANAGEMENT CONSIDERATIONS: The origin of this occurrence, whether natural or associated 

 with disturbance, must first be resolved to determine whether or not it warrants management concern. 

 To help resolve such questions, the species should be sought during range work in this area of the 

 allotment. 



