categories; none were deleted. The list of habitat categories used after 

 March 18, 1977, is presented as table 1. The correlations between the vege- 

 tative community types identified by Prodgers (DNRC 1978) and these wildlife 

 habitat categories are given in table 2. Many community types whicli are very 

 similar in physiognomy and general aspect, or which merely reflect reversal of 

 dominants, were combined into the more general habitat categories. 



A preliminary vegetation map for the proposed mining area (scale:l :12,000) 

 was prepared by R. Prodgers, DNRC plant ecologist, and became available March 

 17, 1977. A similar map for the 75-section vegetation study area became avail- 

 able in July of 1977, but vegetation mapping for the reconnaissance level study 

 area was not completed during the study period. 



Woodland Series 



Cottonwood Forest (CF) . The cottonwood forest (CF), corresponding to the 

 Plains Cottonwood/Western Snowberry-Prairie Rose c.t. and to the western river 

 floodplain forest of Stewart (1975), is characterized by dense stands of riparian 

 plains cottonwood, 20 m (65 feet) or more in height with a well -developed shrubby 

 understory of western snowberry, prairie rose, willow, western serviceberry, choke- 

 cherry, and/or red osier dogwood. The CF h.c. is restricted to the floodplain of 

 the Missouri River and the lower reaches of Sand Creek and Prairie Elk Creek. 



Cottonwood Groves (CG) . Open, scattered stands of plains cottonwood 20 m 

 (65 feet) or more in height lacking the well -developed shrub understory of the 

 CF h.c.'s characterize the CG h.c, found bordering stockponds and reservoirs in 

 more mesic coulees scattered along the upper reaches of major streams. i 



Farm Groves and Shelter Belts (FG) . The FG h.c. consists of areas of 

 dense, isolated stands of introducted tall shrub or tree species (white elm, 

 lombardy poplar, Russian olive, Douglas fir, Englemann spruce, ponderosa pine) 

 usually 4-10 m (13 feet to 33 feet) in height. This habitat category is some- 

 times interspersed with plains cottonwood, and usually surrounds farmsteads. 

 The FG h.c. is similar to the shelter belts and tree claims described by 

 Stewart (1975) in North Dakota. 



Box Elder-Ash (BX) . Corresponding to the Green Ash/Prairie Rose-Western 

 Snowberry c.t., the BX h.c. is characterized by dense stands of riparian box 

 elder, green ash, chokecherry, western serviceberry, western snowberry, prairie 

 rose, and other tall shrubs and trees having an overstory usually 4-10 m (13 to 

 33 feet) in height. It sometimes includes scattered plains cottonwood trees 

 15 m (bO feet) or more in height, and is found along the upper reaches of major 

 streams, notably Prairie Elk Creek, and in very moist coulees. 



Shrubland Series 



Rocky Mountain Juniper (RJ) . Corresponding to the Rocky Mountain Juniper/ 

 Bluebunch Wheatgrass c.t., characterized by scattered individuals of Rocky 

 Mountain juniper usually under 3 m (10 feet) in height. Largely restricted to 

 the northwestern portion of the study area near the Fort Peck Reservoir, this 

 habitat category is usually associated with badlands and dry coulees. 



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