Grassland Series 



Grassland (GR) . This category includes several distinct c.t.'s which are ' 

 similar in physiognomy, difficult to separate at a distance, and which in many 

 cases are distinguished only by a reversal of dominants. These are the c.t.'s 

 dominated by blue grama, needle -and-thread, thread-leaved sedge, green needle- 

 grass, and prairie sand reedgrass. It is by far the predominant grassland hab- 

 itat category in the study area and corresponds to the western mixed-grass 

 prairie of Stewart (1975). 



Western Wheatgrass (WW) . Corresponding to the Western Wheatgrass/Blue 

 Grama and Blue Grama/Western Wheatgrass c.t.'Sjthe WW h.c. is typically found 

 on low to mid slope positions, often on shrubless drainage bottoms, and is fairly 

 easily distinguishable from the GR h.c. at a distance. 



Bluebunch Wheatgrass (BW) . The BW h.c. corresponds to the Bluebunch 

 Wheatgrass/Blue Grama-Thread-leaved Sedge and Plains Muhly-Bluebunch Wheatgrass 

 c.t.'s and is usually found on ridgetops and upper slopes of cool aspect. 



Little Bluestem (LB) . The LB h.c, corresponding to the Little Bluestem 

 and Little Bluestem/Prairie Sand Reedgrass c.t.'s, is dominated by little blue- 

 stem which is very conspicuous and which stands out clearly from the GR h.c. at 

 all seasons. This h.c. is usually found on the downwind side of ridgetops, but 

 occurs on a wide variety of sites from coulee walls to floodplains. 



Saltgrass (SA) . Corresponding to the Saltgrass c.t., the SA h.c. is dom- 

 inated almost exclusively by saltgrass less than 5 cm (2 inches) in height and 

 is usually found on saline flats, floodplains, and alkaline wetlands. < 



Horizontal Juniper (HJ) . Corresponding to the Horizontal Juniper/Little 

 Bluestem-Bluebunch Wheatgrass c.t., the HJ h.c. is dominated by horizontal jun- 

 iper, but is included within the grassland rather than the shrubland series 

 because the juniper is less than 15 cm (6 inches) in height, which is short 

 compared to the subdominant grasses. Usually found on scoria slopes and bad- 

 lands, this h.c. also occurs on steeper coulee walls and coulee bottoms. 



Wetland Series 



Wet Meadow (WM) . The WM h.c, similar to the wet-meadow swales described 

 by Stewart (1975) in North Dakota, is dominated by mesic grasses (bluegrass, tim- 

 othy) in cool, moist drainage bottoms and floodplains. Curl dock is often con- 

 spicuous in moister sites. This h.c. is generally restricted to floodplains of 

 the Missouri River and large perennial streams such as the Redwater River. 



Cattail Marsh (CM) . The CM h.c. includes all wetlands dominated by cattail 

 and is most abundant in the Missouri River floodplain. 



Scirpus Marsh (SM) . Corresponding to the Western Bulrush c.t., the SM 

 h.c includes all wetlands dominated by bulrush and is usually found along stock- 

 ponds, larger reservoirs, and perennial streams. 



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