nearly all river miles were divided between transition and rural 

 settings. Fishing from shore was yet again the most common 

 recreation activity, a primary use on 78 percent of the segments. 

 Canoeing was a primary activity on over 60 percent of the 

 segments, and boat fishing a primary or secondary activity on 78 

 percent. Only 13 percent of the river miles inventoried were rated 

 as not boated. The most common land-based activity was viewing the 

 scenery, with no other activities except picnicking rated as 

 primary uses more than once or twice. Nearly all of the land-based 

 activities included on the segment rating sheet were thought to be 

 secondary activities. 



Botanical Features 



The lower Yellowstone River drainage contained 23 botanical 

 natural feature sites, none of which received a final value rating 

 of Class I. This drainage also contains the second lowest 

 proportion (three percent) of sites that received a final value 

 rating of either Class I or Class II. The fact that this region 

 is sparsely populated and isolated from the rest of the state may 

 have influenced the number of sites that were inventoried for the 

 Montana Rivers Study. 



Two outstanding natural features within this drainage are 

 Seven Sisters and Elk islands on the Yellowstone River. The free- 

 flowing river periodically floods and scours its banks, an action 

 that scarifies the seeds of their cottonwood trees and stimulates 

 germination. Flooding also deposits nutrient-rich, silty alluvial 

 soil along the floodplain, providing cottonwood seedlings with a 

 high quality site for establishment. Cottonwood regeneration 

 depends on periodic flooding that occurs on free-flowing rivers. 



Elm-ash hardwood forests are found in the lower Yellowstone 

 River drainage. Commonly found in the eastern U.S., these 

 hardwood forests are restricted to the extreme eastern edge of 

 Montana. Deciduous woodlands, composed of American elm, green ash 

 and box elder, grow on sandy soils and upland areas along the 

 tributaries of the Yellowstone River. These unique areas are 

 threatened by overgrazing from cattle because they provide 

 succulent forage, drinking water, and shade in an otherwise 

 treeless prairie environment. 



Poker Jim Research Natural Area, a proposed National Natural 

 Landmark (NNL) is located on the North Fork of Jim Creek, a 

 tributary of the Tongue River. The 363-acre area, established as 

 a RNA in 1974 by the U.S. Forest Service, is an excellent example 

 of an undisturbed ponderosa pine forest community, typical of this 

 region. The vegetation on this sandstone plateau is dominated by 

 the ponderosa pine and interspersed with a mixed-grass prairie 

 community of bluebunch wheatgrass and western wheatgrass. 



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