base 0.5-1 mm long, pilose-lanate on the lower half, the 

 segments obovate-lanceolate , the inner ones often 2-3 mm 

 the longer in fruit; filaments pilose; styles slender, 

 about (1) 1 . 5 mm long; ovary glabrous to somewhat pilose 

 above. 



3. Diagnostic characters: E. caespitosum is the only Montana 

 wild buckwheat with a stipitate perianth which has a single 

 involucre. 



B. GEOGRAPHIC DISTRIBUTION 



1. Species range: "...southeastern Oregon to northern and 

 southeastern Sierran California, east to central Idaho, 

 Montana, Wyoming, and Colorado (Hitchcock and Cronguist 1964)" 



2. Montana distribution: Listed for Montana by both Hitchcock 

 and Cronguist (1973) and for southern Montana by Dorn (1984). 

 However, Reveal (pers. commun.) stated that this species was 

 actually not in Montana, but some other species had been 

 mistaken for it. Due to these problems Lesica and Shelly 

 (1991) placed it in the undetermined category, treating the 

 identification of two collections at MONT (Ryerson and Vogel 

 554, W. E. Booth s.n.) as uncertain. The specimen from the 

 Tendoys might be the first verified collection of this plant 

 from Montana, but it is not the first report. 



3. Occurrences in the study area: Found at one location in the 

 southern part. 



C. HABITAT 



The population occurs on dry, rolling uplands in a unusual 

 habitat type dominated by Artemisia arbuscula and Festuca 

 idahoensis . Phlox hoodii and Poa secunda also grew at the 

 site. The soil is a stony loam, derived from limestone. The 

 habitat is grazed. 



D. POPULATION BIOLOGY 



The population was not thoroughly surveyed, but there was a 

 large area of potential habitat. 



E. MANAGEMENT CONSIDERATIONS 



There may be only one verified location for this species in 

 the state. At this time, E. caespitosum should be considered 

 for designation as sensitive by BLM and tracked by the state. 



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