either proposed or already designated Research Natural Areas 

 (RNAs) or National Natural Landmarks (NNLs). 



Three U.S. Fish and Wildlife Service RNAs, Grand, Two Calf, 

 and Dillon, are riparian forest islands that contain cottonwood, 

 willows, and wheatgrass/needlegrass communities. Two Calf Island 

 also contains old-growth Douglas fir, a unique species for a 

 prairie ecosystem. These areas have been protected from grazing 

 by the Missouri River. 



This drainage also contains a U.S. Forest Service proposed RNA 

 and NNL candidate called Paine Gulch, located at the north end of 

 the Little Belt Mountains. This 2,500-acre site sits within a 

 steep-sided gulch that rises from 4,680 feet to 7,213 feet and 

 features limestone benches forested with Douglas fir, limber pine 

 and lodgepole pine. Along with montane and subalpine meadows, the 

 gulch contains numerous seeps, springs, and sinkholes, which 

 commonly occur elsewhere within limestone formations. Paine Gulch 

 has regional significance as an area that contains forest and 

 grassland types characteristic of central Montana. 



A plant species of interest within the central Missouri River 

 drainage is long-styled thistle ( Cirsiu m longistylum ), endemic to 

 Montana and listed as rare by the Montana Rare Plants Project. 

 Found on fewer than a dozen sites within the Little and Big Belt 

 Mountains, this species grows in moist meadows at 5,000 feet to 

 7,500 feet. 



Geologic Features 



Nineteen percent of the Class I and II geologic feature sites 

 identified in the Montana Rivers Study, excluding type locations, 

 were found in the central Missouri River drainage. Further study 

 is likely to identify additional outstanding sites. 



At the city of Great Falls, the Missouri River plunges over 

 Black Eagle, Rainbow, Crooked, and Big (Great) Falls, spectacular 

 falls most easily seen from the road along the bluffs on the south 

 side of the river. Below the falls, the river flows over bedrock 

 shelves, and in the summer, drops of one to three feet extend 

 across much of the river. Although maps indicate rapids farther 

 downstream in the white cliffs area, they are more like large 

 riffles. 



About 50 miles to the northwest of Great Falls, in the reach 

 between Coal Banks Landing and the mouth of the Judith River, the 

 Missouri River threads its way between spectacular cliffs of white 

 colored Virgille sandstone. Atop the white sandstone is a dark 

 colored layer of sandstone more resistant to weathering than the 

 underlying white sandstone. This resistant cap has caused the 

 sandstone to weather into odd shapes known as "hoodoos," best seen 

 in the vicinity of Eagle Creek. Just below Eagle Creek, a series 



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