Engineers land, near the Confluence of the Kootenai and Fisher Rivers (051) a 

 subpopulation is on Plum Creek Timber Co. land, and at Magnesia Creek (029) the 

 population extends onto private land. Additional occurrences are likely on private lands 

 m creek bottoms which have not been surveyed. 



I. Assessment and management recommendations 



1. Threats to currently known populations: The major threats to Cvpripedium calceolus 

 var. parviflorum on the KNF are road building and cattle grazing, but logging may have 

 indirect effects, and there is a potential for populations to be threatened by collection of 

 plants by the general public. Any other activities which impede or reduce groundwater 

 flow at its population sites are also threats. 



Two populations, Dickey Lake (001) and Therriault Creek (030), have been impacted by 

 the recent reconstruction of U. S. Highway 93 and remain at risk due to silt runoff and 

 accumulation above the population areas (see slides 6, 7, 16, and 17 in Appendix C); the 

 Therriault Creek population has been nearly extirpated and is likely to become so if 

 protective measures are not taken. It is also likely that road construction has reduced 

 population areas at Brimstone Creek (026) and Butler Creek (013) both of which are 

 bisected by gravel roads. Damage from road construction at these sites, however, seems 

 to be stabilized at this time. Populations of sensitive orchids on the KNF often occupy 

 level topographic positions which are favored for road routes, especially stream crossings. 



The threat from cattle grazing is speculative but persuasive, supported by inference on the 

 KNF and the Custer National Forest. Seemingly suitable habitats which are grazed have 

 few or no lady's slippers, and the areas which support the orchids have little or no 

 evidence of cattle use. In the area of Homes Lake (028), where a low level of grazing was 

 noted in 1991, the plants were confined to hummocks protected by brush (Chadde 1991). 

 I revisited this population in 1995 and observed fewer plants than reported in 1991 and 

 these had low vigor (slide 9, Appendix C), but I found little evidence of recent grazing. I 

 searched the drainage of Lime Creek and found heavy grazing but no Cvpripedium . 

 however, later in the season Jack Triepke found a few stems in the area (occurrence 055), 

 verifying that the habitat is appropriate for the orchids. Another sensitive orchid, Orchis 

 rotundifolia . occurs in this drainage and was relocated in grazed habitat in 1995, but it is 

 likely that the low growing and non-rhizomatous habit of this plant make it more tolerant 

 of grazing. The fragile rhizomatous habit of C. calceolus var. parviflorum probably 

 makes the plants highly susceptible to trampling, and its succulent, upright foliage may be 

 palatable to cattle. Heavy grazing is also likely to effect the hydrology of riparian zones. 

 Most of the known populations on the KNF are within range allotments. On the 

 Sheyenne District of the Custer National Forest all occurrences of C calceolus var. 

 parviflorum are within grazing allotments, but three are restricted to exclosures and the 

 others are in very low numbers or otherwise difficult for cattle to access (North Dakota 

 Parks and Recreation Department 1 990). 



Logging and road building adjacent to population areas may threaten the plants by 

 making the sites more accessible to cattle and by affecting the hydrology of the sites. The 

 riparian areas where Cvpripedium calceolus grows on the KNF are generally excluded 

 from logging by management guidelines. Logging of surrounding forests may have 

 effects on the hydrology of the population sites, but these are difficult to predict. 

 Changes to the hydrology can be expected to affect the populations and potential habitat. 

 Lady's slippers are the among the most beautiful flowers known and are coveted as cut 

 flowers and for propagation as ornamentals; the rhizomes were historically in high 

 demand for their reputed medicinal properties (Correll 1950), and continue to be offered 



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