and Clark National Forest along the Rocky Mountain Front Range. A very large 

 population with as many as 3,000 estimated stems was also reported from private land 

 near Whitefish. 



On the Kootenai National Forest, estimated population size ranges from less than 1 

 stems at Glen Creek (054) and Lime Creek (055), to perhaps more than 1,000 stems in 

 several subpopulations across over 20 acres along Magnesia Creek (029). Relatively 

 large, vigorous populations covering significant areas are also found at Brimstone Creek 

 (026) and in the Hidden Lake Area (027). Evidence of population decline was found by 

 1995 census numbers, compared to numbers from 1989 and 1991, at Dickey Lake (001) 

 and Therriault Creek (030), both sites which were impacted by highway construction in 

 the last few years (see slides 6, 7, 16, and 17 in Appendix C). The Therriault Creek 

 population is nearly extirpated and remains in grave danger as silt fills the remaining 

 small area of habitat. Fewer stems were also seen in the Homes Lake Area (028) which 

 has received light use by cattle. There is, however, possible evidence of population 

 growth over the same period at Butler (013) and Brimstone (026) Creeks. Estimates of 

 population numbers and area are given, as available, in the element occurrence data and 

 size fields of the Element Occurrence Records in Appendix A. 



Reproductive biology: The reproductive biology of orchids in general is characterized 

 by complex floral morphologies and mechanisms adapted to cross pollination by insects, 

 and by the production of tiny seeds, potentially in great numbers, which can be dispersed 

 long distances but which are dependent upon fungi for seed germination and seedling 

 development. 



Most species of Cypripedium are thought to depend on cross-pollination for sexual 

 reproduction (Bernhardt 1990). In an examination of living material which included C 

 calceolus var. parviflorum . Catling (1983) found no evidence of self-pollination in the 

 genus except for C passerinum . High levels of heterozygosity found in populations of C 

 calceolus var. parviflorum and other varieties of the species are also consistent with an 

 outcrossing breeding system (Case 1993). Flowers of the lady's slippers are thought to be 

 adapted to pollination by a variety of insects, including beetles and flies (Correll 1950), 

 but bees are probably the primary pollinators for the genus (Bernhardt 1990, Catling 

 1983). 



Germination of terrestrial orchid seeds depends on penetration by fungal hyphae, and the 

 plants grow underground as colorless mycorhizomes for a period of time before 

 producing photosynthetic tissue (Wells 1981). Data from Europe (cited in Wells 1981) 

 indicate that plants of Cypripedium calceolus are very slow to mature, producing their 

 first leaves four years after germination and first flowering after about 16 years. 



Cypripedium calceolus var. parviflorum reproduces both vegetatively, by rhizomes, and 

 sexually, by seeds, although the relative degree of each method in a population is difficult 

 to determine. Bernhardt (1990) speculates that large colonies of lady's slippers may be 

 clonal and fail to produce fruit due to low rates of cross-pollination. Poor fruit 

 production has been noted in many Montana populations of C. calceolus . var. 

 parviflorum . On the KNF most population surveys have been conducted in June when 

 the plants were flowering, however, fruits have been observed at a few sites at later dates 

 (see the element occurrence data fields on the Element Occurrence Records in Appendix 

 A). The presence of flowers is not necessarily an indication of reproductive success and 

 numbers of aerial stems are not a true indication of population size or condition. 

 Vegetative reproduction allows a population to persist and spread locally, but alone does 

 not supply genetic variation which allows the population to adapt or seeds for long 

 distance migration. 



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