3. Occurrences on the Gallatin National Forest: Two records 

 from the Forest are entered in the Biological Conservation 

 Database, one from Horsefly Pass in the Crazy Mountains, the 

 other on Mt. Bridger in the Bridger Range. These are based on 

 old (1902 and 1903 respectively) J. W. Blackenship collections 

 at MONT which are labeled P. multisecta. Plants which I 

 collected from Mt. Bridger and from the vicinity of Sacagawea 

 Peak closely resemble these historical collections, however, 

 all of these plants, and all other pinnate leaved specimens of 

 P. diversifolia at MONT, key out to var. perdissecta , with 

 sparsely hairy, greenish leaves. A Rydberg and Bessey 

 collection from the Bridgers, morphologically similar to 

 Blackenship's collections, is also at MONT; this is labeled P. 

 decurrens Rydb. , a synonym for P. diversifolia var. 

 perdissecta. The type collection of P. decurrens came from 

 the "Spanish Peaks, Madison Range, Montana" (Hitchcock and 

 Cronquist 1961) . My impression is that pinnate leaved forms 

 of P. diversifolia in the Bridgers are best described as P. 

 diversifolia var. perdissecta. All of my Potentilla specimens 

 were sent to Barbara Ertter (University of California - 

 Berkeley) who is currently working on a revision of the genus. 

 She is not willing, at this point, to make determinations of 

 these specimens (or to concur with mine) , and feels that past 

 treatments may not adequately describe the variation in this 

 group. While the Gallatin National Forest material seems to 

 align with P. diversifolia var. perdissecta , further taxonomic 

 work is needed. The two records of P. diversifolia var. 

 multisecta will be removed from the Biological Conservation 

 Database as invalid entries. 



C. HABITAT 



P. diversifolia was seen in a broad range of montane to alpine 

 habitats on the GNF. Pinnate leaved forms, however, were 

 found only at higher elevations along the crest of the Bridger 

 Mountains. These plants grew in rocky areas in open, low 

 statured forests (Douglas fir on the west side, Engelmann 

 spruce on the east) , and above timber on talus slopes, rock 

 outcrops, and in rocky tundra. 



D. POPULATION BIOLOGY 



The populations of pinnate leaved P. diversifolia were 

 extensive along the crest of the Bridgers. These populations 

 were always intermixed with P. diversifolia var. diversifolia , 

 and at times with P. ovina. Species of Potentilla commonly 

 hybridize, forming apomictic clumps (Ertter, pers . commun.). 

 Pinnate leaved "P. diversifolia" may represent hybridization 

 with P. ovina. 



E. MANAGEMENT CONSIDERATIONS 



Although Hitchcock and Cronquist (1973) give a Montana 

 distribution for P. diversifolia var. multisecta, I have seen 

 no collections from the state which match their description or 



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