68' Canadian Forestry Journal 



slopes, and reaches above timber line. The miners call this shrub 

 *' buckbrush." The moose sometimes eat it when they cannot 

 obtain willows. ; jrij n , 



Along the river banks the alder, willow arid "brier-rose are 

 abundant. 



(jehefally speaking, travelling on foot is easy through the 

 forests of the Yukon. There is not the dense growth so often 

 encountered in the north and east. 



The thin growth is probably due to the permanently frozen 

 ground just below the forest floor. The tree roots are unable to 

 strike down, and the trees, as they grow taller, are compelled to 

 buttress themselves against wind pressure by the spread of their 

 roots. As the roots spread over the surface, only a limited num- 

 ber of trees can exist on a given area, and the weaker trees decay 

 for lack of sufficient nourishment. 



In the Klondike district. Professor Macoun has observed 

 that trees on southward-facing slopes, at a height of 1,500 to 2,000 

 feet above Dawson, are not only better grown and larger but also 

 have roots which strike deeper than trees of the valley flats. He 

 explains that this is due to the sunshine not being cut off from 

 this elevation by the hills on the opposite side of the valley as 

 it often is on the valley bottom, and as a result of this a deeper 

 layer of loose material is thawed out on the higher elevations. 



Considerable forest fires occurred immediately after the 

 influx of gold seekers in 1897 and '98, and since then fires have 

 been frequent every summer. Most of the fires were due to care- 

 less and inexperienced campers ; many are due lately to miners 

 who take no precaution against the spreading of fire when clear- 

 ing their claims. 



A serious disadvantage on many gold-bearing creeks is the 

 scarcity of water for mining operations. This is sometimes the 

 result of burning the forest covering and moss on the headwaters 

 and slopes above the stream, so that the moisture is no longer 

 conserved and sent down the hillsides in a steady supply during 

 the summer. Landslides sometimes occur on hillsides as a result 

 of forest denudation, especially on slopes where the rock waste 



