324 



FOREST PRODUCTS 



GROUND LINE AND HEIGHT OF TREATMENT FOR WESTERN RED CEDAR 



POLES 



Photograph bv U. S. Forest Service . 



FIG. 88. Pole yard and treating plant at Gaulsheim, Germany. Note the straight, uniform 

 character of the poles. These are largely composed of spruce and fir. 



In 1915, 6,295,284 cu. ft. of piling were treated largely by creosote 

 and the pressure process. This is equivalent to 9,352,778 cu. ft. of 

 piling or 467,639 piles each of 2o-ft. length. 



It is very necessary that all bark be carefully peeled before treatment 

 and that large amounts of creosote oil be forced into the wood. If the 

 piles are subject to attack in salt waters, from 1 8 to 24 Ib. of creosote per 

 cubic foot are advisable; if free from attack, from 10 to 14 Ib. of oil 

 per cubic foot is regarded as sufficient to retard decay. The full cell 

 or Bethell process of pressure treatment in large cylinders is the method 



