250 THE PRINCIPLES OF HANDLING WOODLANDS 



least interfere with skidding the logs. Small fires art 

 started, and as the branches are cut off the trimmers 

 throw them on the nearest fire. One reason why this 

 method is cheaper than the others is because the branches 

 need not be cut up so small, for the fire is already burn- 

 ing when they are thrown on. In coniferous forests 

 the tops burn readily, even on the snow or in stormy 

 weather. Sometimes when it is not practicable to start a 

 fire near a given top, the trimming of the limbs is de- 

 ferred until the skidders can haul it bodily near a fire. 

 The branches are then lopped and the last cut made, 

 enabling the skidders to go on with the top log, while 

 the choppers throw the brush on the fire. 



If the work is systematized, the brush is practically 

 all disposed of as the logs are skidded, and the woods are 

 cleaned up as the logging proceeds. There is a distinct 

 advantage to the skidders through having open ground 

 to work over. This method should be used only when 

 there is no danger of a spread of fire. Its use on a large 

 scale is confined to logging during the season of snow or 

 rain. 



The best method of calculating the cost of brush dis- 

 posal is on the basis of the amount of timber cut, meas- 

 ured in board feet, log measure. A determination of 

 cost per acre would be misleading, because of the great 

 variation of yield in different forests. 



The cost varies widely under different conditions. 

 If trees have heavy crowns and large, heavy limbs, the 

 cost is much greater than where the crowns are smaller 



