Similar rapid development of woody shrubs through adventitious stem 

 development occurred in I- to 2-ha areas at both Middle Fork Koyukuk River- 

 Downstream and Aufeis Creek study sites. However, at these sites the slash 

 and woody debris were not piled, but were spread over the ground at the 

 edge of the disturbed areas (Figure 69). 



Figure 69. Distribution of woody slash debris and other 

 organics over the ground on the edge of the gravel removal 

 area at Aufeis Creek. 



At the Tanana River-Downstream site overburden from the 5-ha pit was 

 placed in contoured banks surrounding the flooded pit. These overburden 

 piles were approximately 2 to 3 m deep inversely piled (top material covered 

 by bottom material), and consequently contained no organics or woody remains 

 near the surface. However, an early shrub community dominated by Popu I us 

 balsamifera, S. alaxensis, and AInus crispa, with a density of 230 stems 

 per 0.004 ha, was present during the fourth growing season following gravel 

 removal. This shrub community developed from seed and invaded in mass during 

 the first growing season. The shrubs occurred in uniform density over approx- 

 imately 60 percent of the gently-sloped, 20 to 25 m wide overburden banks 

 surrounding the pit. 



Rapid natural reco I on i zat i on of disturbed areas was not always limited 

 to overburden piles. At the Jim River, West Fork Tolovana River, and 

 Prospect Creek, pioneer communities were well developed at the end of the 



236 



