Montana but is not included in Dorn's (1984) flora of the 

 state. 



2. Montana distribution: All known populations occur in 

 Beaverhead County within the boundaries of the present study 

 area . 



3. Occurrences in the study area: There are six sites known, 

 (four discovered by this project) distributed around the 

 periphery of the Tendoys. These are from Big Sheep Creek, 

 Bell, and Limekiln canyons and from above Johnson Gulch. 



C. HABITAT 



Cronquist et al. (1984) describe the habitat as "stony, often 

 calcareous slopes." Within the study area, P. incana grows in 

 ephemerally moist patches of soil or litter on dry limestone 

 talus slopes (slide 16 in Appendix E) . Dominant woody 

 vegetation on these slopes is Artemisia tridentata or 

 Cercocarpus ledifolius . P. incana often grows beneath these 

 shrubs. Additional associates include Collinsia parviflora, 

 Cryptantba watsonii, Descurainia richardsonii , Phacelia 

 hastata, and P. linearis . Four associated MPSSC are 

 Agastache cusickii, Hutchinsia procumhens , Mimulus suksdorfii 

 and Stanleya viridiflora. The Mimulus seems to be especially 

 close in microhabitat preference. 



D. POPULATION BIOLOGY 



The populations discovered in 1993 ranged in estimated numbers 

 from 50 to as many as 10,000 plants. The species was 

 considered "common" at the other two previously known sites. 

 The population in Big Sheep canyon was revisited during 1993 

 and plants were readily found. 



E. MANAGEMENT CONSIDERATIONS 



This species has a very limited known distribution in Montana. 

 Like its associate, Mimulus suksdorfii , it is very easily 

 overlooked and future surveys may reveal that it is more 

 common. However, at many of the Mimulus sites the Phacelia is 

 absent, whereas the Mimulus is usually present at the Phacelia 

 sites. Four rare species, including P. incana, are present at 

 the upper Big Sheep Canyon site (see management considerations 

 for Agastache cusickii) , thus, protection of the habitat on 

 these talus slopes should be given high priority. The other 

 populations of P. incana are more remote and are not 

 immediately threatened. This species should continue to be 

 tracked by the Montana Natural Heritage Program and is 

 recommended for ELM sensitive species designation. 



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