The Nature Conservancy's Crown B tte Preserve about 35 miles 

 west of Great Falls near the headwaters of Little Muddy Creek is 

 considered a high priority site for National Natural Landmark 

 (NNL) designation. Crown Butte is a laccolith, an igneous 

 intrusion formed when a pocket of magma was thrust between layers 

 of sedimentary rock. Due to an absence of grazing as a result of 

 its inaccessibility, the 657-acre site supports native grassland 

 vegetation in pristine condition. This grassland cover type, 

 dominated by bluebunch wheatgrass ( Agropyron spicatu m) and rough 

 fescue ( Festuca scabrella ), is commonly found throughout the east 

 front of the Rocky Mountains and parts of eastern Montana. 



The Green Timber Basin-Beaver Creek area, a proposed Research 

 Natural Area (RNA) and a high-priority candidate for National 

 Natural Landmark designation, is within the Beaver Creek drainage 

 along the eastern front of the Rocky Mountains. This creek basin 

 contains numerous limestone cliffs and rock outcroppings in the 

 midst of a forest of spruce and Douglas fir. Although the area has 

 been roaded, logged, and grazed by cattle, it possesses some of 

 the rarest orchids found in Montana. The round-leaved orchid 

 ( Orchis r otundif oli a) and northern lady's- slipper (C ypripedi um 

 passerinu m) are found in only three or four places in the western 

 Continental U.S. In fact, the northern lady' s-slipper is only 

 found only in four locations in Montana and nowhere else. Six 

 other orchids found in the areas around cold limestone springs and 

 seeps are fairy-slipper ( Calyps o bulbos a) , Wister coral-root 

 ( Corallorhiza wi steriana ) , Gray bog-orchid ( Habenaria viridis ), 

 Alaska rein-orchid (H. unalascensis ) , small northern bog-orchid 

 (H. obtusata ) and northern twayblade ( Listera borealis ). 



Another candidate for NNL designation is the Sun River Game 

 Range west of Choteau along the Sun River. This 19,728-acre area 

 is owned by the state and is administered by the MDFWP. The game 

 range extends from the prairie foothills at about 4,300 feet to 

 alpine meadows at 8,100 feet. Despite the fact that part of this 

 area has been heavily grazed and logged in the past, a large 

 portion of the area is native vegetation in excellent condition. 

 This is the only game range in the state currently under 

 consideration as a NNL. 



Pine Butte Swamp Preserve, a Nature Conservancy sanctuary of 

 about 20,000 acres, contains a unique peatland bog or fen, 

 underlain by glacial till derived from the calcareous outwash of 

 the Rocky Mountain Range. Water from the Teton River seeps 

 through this permeable material to form the swamp. The swamp 

 contains open fen community type vegetation composed of mosses, 

 forbs, and grasses. One example of a sedge present in calcareous 

 bogs of this type is pale sedge (C arex livida ) , a species 

 currently listed by the Montana Rare Plants Project as rare for 

 Montana. The shrub vegetation along the uplands and on high 

 ground within the swamp is dominated by willow, bog birch ( Betula 

 Si§.Il^!ii21l) • and red-osier dogwood (Cornu£ H olonif e ra ) . 

 Peatlands or fens like Pine Butte generally occur in boreal 



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