undulate-crenate and retuse terminal lobe, more or 

 less greenish around the basal orifice leading 

 into a slightly curved spur 5-6 mm. long; column 

 3-4 mm. long, somewhat wing-margined above the 

 orifice to the spur; ovary green to purplish, 

 thick, pedicellate; 2N=42 (adapted from Hitchcock 

 et al. 1969; Williams and Williams 1983). 



3. LOCAL FIELD CHARACTERS: Orchis rotundifolia is 

 .,-. the only member of the orchid family in Montana 



which has a single basal leaf and white flowers 

 with purple-spotted lip petals; it would not be 

 readily confused with any other species in the 

 state. 



D. GEOGRAPHICAL DISTRIBUTION 



1. RANGE: Orchis rotundifolia is generally a boreal 

 species, distributed from Alaska to Greenland, and 

 extending south to southern British Columbia, 

 northwestern Montana, northwestern Wyoming, 

 Minnesota, Michigan, Wisconsin, and New York 

 (Hitchcock et al. 1969; Williams and Williams 

 1983) . The species is known to occur on the 

 Flathead and Lewis & Clark national forests, in 

 Region 1 (Northern Region) of the U.S. Forest 

 Service. The distribution of 0. rotundifolia in 

 Montana is shown in Figure 1, p. 4; it has been 

 recorded in Lewis & Clark, Pondera, Powell, and 

 Teton counties. The exact locations are indicated 

 on the maps provided in Section IV, pp. 41-53. 



2. CURRENT SITES (MONTANA): Orchis rotundifolia is 

 recently documented (1988) from 17 sites; two of 

 these are in the Bob Marshall Wilderness Area, and 

 15 are in the Front Range mountains east of the 

 wilderness boundaries. The locations of these 

 sites, including the legal descriptions, latitude 

 and longitude, elevations, and USGS topographic 

 quadrangle names, are provided in Table 1, p. 5. 

 These are subdivided to indicate those sites which 

 occur wholly or partially on U.S. Forest Service 

 lands (Table lA) , and the sites which occur on 

 lands not managed by the U.S. Forest Service 

 (Table IB) . Field surveys were conducted by the 

 author on 20 June-1 July, and 12 July, 1988. 

 Assistance with field research was provided by 

 Angela Evenden, Maria Ash, Wayne Phillips, and 

 Dana Field (U.S. Forest Service) , Lisa 

 Schassberger (Montana Natural Heritage Program) , 

 and Cary Lund. 



Throughout this report, the three-digit occurrence 

 numbers are indicated in parentheses after the 



