can drive to the ledge, unload the boat, paddle across, surf to 

 his or her heart's content, and paddle back. And no shuttle! 



Botanical Features 



The upper Clark Fork drainage contains 103 of the 400 

 botanical natural feature sites inventoried in this study. This 

 phenomenon may be a result of an uneven research effort, due to 

 the proximity of Missoula and the University of Montana. This 

 drainage contains the largest number of natural feature sites -- 

 52 sites or 23 percent of the total 228 -- that received a final 

 rating of either Class I or Class II. Nineteen of the 103 

 botanical natural feature sites are located in U.S. Forest Service 

 wilderness areas. 



A unique plant in this drainage is the Bitterroot trisetum 

 ( Triset um orthochaet um) , known only from the Lolo Hot Springs 

 area. This species was discovered in 1951, but it could not be 

 relocated until recently, when it was found five miles from its 

 original site. Botanists believe the plant may be a sterile 

 hybrid. 



An endemic plant species found within this drainage is 

 Sapphire rockcress ( Arabis fecunda), a recently described species 

 known only from Ravalli County, Montana. This rare plant grows on 

 scattered sites of calcarious soil that occur in two small areas 

 in the Sapphire Mountain Range. Another unusual plant in the 

 drainage is the giant helleborine, ( Epipactis gigantea ). Although 

 fairly common in the southern part of its range, it is listed as 

 an endangered species in this region. Here, at the northern limit 

 of its range, this shallow-rooted orchid can be found near warm 

 springs, and it is threatened by the development of these areas. 



A regionally endemic plant found within the upper Clark Fork 

 drainage is Howell's gumweed (Grin deli a howe llii ), a species of 

 moist prairies, meadows and disturbed areas such as road 

 shoulders. This plant is threatened by heavy grazing, land 

 development and the invasion of spotted knapweed (Centaurea 

 maculosa ), and is a candidate for listing as an endangered species 

 by the U.S. Fish and Wildlife Service. 



An outstanding Research Natural Area (RNA) within the upper 

 Clark Fork River drainage is the Lost Horse Canyon, a major 

 drainage on the east side of the Bitterroot Mountains. Within 

 this area are three proposed RNAs totaling 5,679 acres: the 

 Bitterroot Mountain Snow Avalanche, the Upper Lost Horse Canyon 

 and Lower Lost Horse Canyon. As of 1986, only the Upper Lost Horse 

 Canyon RNA has been officially designated for protection. This 

 RNA features 2,025 acres of subalpine zone forest. The Lower Lost 

 Horse RNA features a mid-elevation montane mixed-coniferous 

 forest, and the Bitterroot Mountain Snow Avalanche RNA contains 



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