(observed at Doherty and Dutchman Mountains, Jefferson and 

 Beaverhead counties, respectively) . Other species of 

 Delphinium seen in this study area are tall plants which grow 

 in wetter areas and bloom later in the season. 



B. GEOGRAPHIC DISTRIBUTION 



1. Range: The range of this undescribed taxon is not yet known 

 but apparently it is endemic to Montana. 



2. Montana distribution: Similar material has been collected 

 from the Pryor Mountain desert (Carbon County) , the Big Belt 

 Mountains (Lewis and Clark County) , the Jefferson River 

 drainage (Broadwater and Jefferson Counties; Vanderhorst 

 1993a) , and Pioneer Mountains (Vanderhorst 1993b) . 



3. Occurrences in the study area: Six populations were 

 located, four of them in the northeastern foothills of the 

 range, the others on hills above Big Sheep Creek in the 

 southern part. 



C. HABITAT 



In the Tendoys, these plants occur on rolling uplands, in 

 shallow, gravelly soils on limestone bedrock (slide 8 in 

 Appendix E) . They occur in communities dominated by grasses 

 {Agropyron spicatum, Poa secunda) and/or shrubs {Cercocarpus 

 ledifolius) or in small patches of soil on mostly barren rock 

 pavement. Other plants commonly associated include Allium 

 textile, Artemisia frigida, Oryzopsis hymenoides , and 

 Penstemon aridus. This taxon seems to be more tightly 

 restricted to edaphic substrate than the common D. hicolor, 

 occurring in the study area almost exclusively on shallow, 

 limestone derived soils. 



D. POPULATION BIOLOGY 



The populations were generally large, with estimated numbers 

 between 200 and 10,000, but one occurrence consisted of a 

 single plant. Private land adjacent to the lone individual 

 was not surveyed and may have been potential habitat for a 

 larger population. The populations in the northeast are close 

 to each other, with patchy distribution of plants in suitable 

 habitat; further survey is likely to reveal a patchy 

 distribution throughout these foothills. Plants were blooming 

 but not yet in fruit when they were surveyed in early June. 

 One population had numerous, small vegetative plants, evidence 

 of successful reproduction. 



E. MANAGEMENT CONSIDERATIONS 



This is an undescribed state endemic taxon which has been 

 misidentif ied in the past as D. andersonii or D. geyeri , both 

 species with a broad range. Specimens have been sent to 

 Michael Warnock who plans to name the taxon as a subspecies of 

 D. hicolor. Due to its status as a Montana endemic this taxon 

 should continue to be tracked by the Montana Natural Heritage 



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