corniculate at apex; achenes 4-5 mm long, murications 

 rather spinelike, reddish or reddish-brown. 



3. Diagnostic characters: differs from exotic dandelions by 

 having mostly entire leaves. Distinguished from the other 

 native species by having reddish-brown fruits and by its 

 involucre bracts which do not usually have a terminal horn- 

 like appendage (adapted from Dorn 1984). 



B. GEOGRAPHIC DISTRIBUTION 



1. Species range: Hitchcock and Cronquist (1973) describe the 

 distribution as "cordilleran, " meaning of the mountains of 

 western North America. The species is infrequent and widely 

 scattered on tundra in Colorado (Weber 1987) and occurs mostly 

 in the mountains in Wyoming (Dorn 1992) , but is not listed by 

 Welsh (1987) for Utah. 



2. Montana distribution: Collected twice from Beaverhead 

 County in the 1980' s and once from Madison County in 1892. 



3. Occurrences in the study area: Known from a 1984 Klaus 

 Lackschewitz collection taken from near the confluence of 

 Meadow and Big Sheep Creeks. This species was found nearby by 

 this project in the bottom of Pileup Canyon; two 

 subpopulations were surveyed, one by each of the authors. 



C. HABITAT 



The Pileup Canyon population occurs in moist alluvial 

 bottomland dominated at one site by big sagebrush (Artemisia 

 tridentata var. tridentata) and Great Basin wild rye {Elymus 

 cinereus) . A slide (18) of this site is included in Appendix 

 E. Dominants at the subpopulation further up the canyon are 

 Douglas fir {Pseudotsuga menziesii) and Idaho fescue {Festuca 

 idahoensis) . Taraxacum eriophorum was growing in partial 

 shade at both sites. The sites were heavily trampled and 

 grazed and had many weeds including a heavy infestation of a 

 common introduced dandelion, Taraxacum laevigatum. The soil 

 is silty. 



D. POPULATION BIOLOGY 



Vanderhorst counted only 28 plants. Lesica estimated less 

 than 50 plants at the subpopulation further up the canyon. 

 Both subpopulations covered small areas. In 1984, 

 Lackschewitz described a population nearby as "extensive," but 

 this occurrence was not relocated by this project. Plants 

 were in a fruiting stage by mid-June. Many of the heads were 

 browsed, possibly by cattle. In spite of this, some mature 

 dispersing fruits were observed. 



E. MANAGEMENT CONSIDERATIONS 



This species appears to be extremely rare within the study 

 area and is uncommon throughout its range. The report of an 



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