River systems of the Northern Interior exert varying degrees of influence 

 on overall scenic quality. The large, active f I oodp I a i n of the Dietrich River 

 covers nearly one half of the valley floor. This river flows in braided pat- 

 tern over much of its length. Numerous light colored unvegetated gravel bars 

 in the active floodplain sharply contrast with the remaining vegetated valley 

 f loor and val ley wa I Is. The Middle Fork Koyukuk River varies from a large, 

 sinuous single channel to a braided system with a large main channel. Through- 

 out, there are many abandoned channels, vegetated islands, and terraces. Both 

 Jim River and Prospect Creek are smaller, sinuous to meandering and less 

 dominant in local scenic quality than the Dietrich and Middle Fork Koyukuk 

 Rivers. AM Northern Interior study sites are in an enclosed landscape where 

 the rivers become a focal point given their prominent and central location. 



The vegetation along the floodplains and hillsides is a diverse mixture 

 of coniferous and deciduous trees of varying ages and densities. Dark-green 

 white spruce trees contrast with the rounded, lighter green deciduous trees 

 and willow thickets. High-water and abandoned river channels have created 

 broken patterns in the vegetation throughout the floodplain. A rich, complex 

 visual texture has developed because of the variable heights and colors of the 

 vegetative communities. 



Color variety is further enhanced by the gravel deposits in the flood- 

 plains, local patterns of vegetation, and in some areas extensive rock out- 

 crops. During fall, vegetative changes introduce another dimension of color 

 variety with the seasonal colors of red, orange, and ye I low added to the land- 

 scape. 



The most noticeable cultural modifications in the Northern Interior are 

 those associated with the Trans-Alaska Pipeline System. Facilities adjacent to 

 the study sites include construction and maintenance camps, airstrips, ma- 

 terial and disposal sites, and elevated and buried pipeline. Spur dikes have 

 been built into the floodplain in several locations along the Dietrich and 

 Middle Fork Koyukuk Rivers. The light colored gravel materials used to con- 

 struct the pipeline work pad, Haul Road, and camp facilities sharply contrast 



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