northeastern comer of the state. Nonetheless, this arid region 

 of short-grass prairie contains some outstanding natural features. 

 One prime example is U.L. Bend, a part of the 1-million-acre 

 Charles M. Russell National Wildlife Refuge that encircles the 

 Fort Peck Reservoir. This site was grazed by domestic livestock 

 until 1969, but has retained its near-pristine grassland 

 qualities. The area is dominated by bluebunch wheatgrass and 

 associated species, including prairie junegrass, prairie sandreed 

 and milkvetch. 



Prairie Dog Island in the southeastern corner of Fort Peck 

 Reservoir is a designated U.S. Fish and Wildlife Service Research 

 Natural Area (RNA) and part of the Charles M. Russell National 

 Wildlife Refuge. This 15-acre island contains undisturbed shrub- 

 steppe and wheatgrass/needlegrass prairie vegetation. 



South of the small town of Bainville and less than five miles 

 from the North Dakota border is the site of a population of 

 nannyberry (V iburnu m lentag o) -- a shrub listed as rare by the 

 Montana Rare Plants Project. In Montana, this shrub only grows in 

 a few locations along the eastern edge of the state. Also located 

 within this general area are two botanical natural feature sites 

 that contain large stands of mature Plain's Cottonwood. 



Geologic Features 



Seven percent of the Class I or II geologic feature sites 

 identified in the study, excluding type locations, were found in 

 the lower Missouri region. Further study is likely to reveal 

 additional outstanding sites. 



Along the Milk River, features relating to continental 

 glaciation are especially prominent. The Milk River Valley was 

 once occupied by the Missouri River, but as the glacial ice sheets 

 pushed south from Canada, the river was moved to the south. By 

 the time the ice sheets retreated, the Missouri had cut a new 

 channel for itself in its present location. Consequently, the 

 Milk River occupies a valley that is much wider than one would 

 expect for a river its size. 



Flaxville gravels found between Scobey and Flaxville reveals 

 clues as to the nature of the continental ice sheet. Here, an 

 area of about 1,000 square miles extending from Opheim to Peerless 

 and south into the Fort Peck Indian Reservation contains no 

 glacial till or evidence of being glaciated. This remnant must 

 have stood as an island in a sea of ice. 



The dry, shaley badlands surrounding Fort Peck Reservoir are 

 thought to hold an abundance of fossils. "Mort," the fossilized 

 skull of a triceretops found from this area, is on display at the 

 Museum of the Rockies in Bozeman. The museum at Fort Peck also 

 contains an impressive display of fossils, many of which were 



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