Western Fir, Pine and Cedar Stumps 



In the States of Washington, Oregon and parts of California, where 

 the rainfall is large and the ground in the forests is always damp, many 

 of the trees grow to great size some being eight or ten feet in diameter. 

 The roots of these trees usually spread out near the surface and do not 

 grow deep into the ground as might be expected, tap roots being ex- 

 tremely rare. 



The object when blasting these stumps is not to split them but 

 to bring them out entire at one blast, with all of the roots possible, 

 because if the charge of explosives is so gauged and located as to split 

 the stump, it generally fails to bring out all of the pieces. As the prin- 

 cipal object is to get out as much of the stump as possible at a minimum 

 cost, it is better to blast it out first and then it can be easily split after- 

 wards by means of a small quantity of dynamite exploded in auger holes. 



The common rule in blasting these stumps is to use one and one-half 

 pounds of Hercules Powder-Stumping L. F. per foot of diameter, with 

 stumps up to four feet, when the subsoil is clay. For larger sizes from 

 two to two and one-half pounds for each foot in diameter should be used. 

 Stumps in gravelly or loose ground require one pound more for each 

 foot in diameter. 



The charge of explosives is best placed when there is sixteen to 

 twenty-four inches of earth between it and the bottom of the stump. 

 This results in the force of the explosion radiating to all sides, lifting 

 the stump clear of the ground, and bringing with it the greatest length 

 of roots. If the charge is placed too close to the stump, the effect is to 

 split it, leaving the roots to be dug out at extra labor and expense. 



When these stumps are large the bottom of the borehole is "sprung" 

 or chambered until it is so large that the increased charge required can 

 be concentrated under the center of the stump. The chambering is done 

 by exploding without tamping, first a half cartridge, then several suc- 

 cessive charges of from one to five cartridges each in the bottom of the 

 borehole. When the hole is large enough it is given time to cool off and 

 is then charged with the necessary quantity of Hercules Powder-Stump- 

 ing L. F. to bring out the stump. Under no consideration should the hole 

 be charged until it has had time to cool off. 



The best plan is to work on other stumps awhile to give the chamber 

 time to cool. 



See pages 119 to 126 for proper methods of priming, charging, 

 tamping and firing. 



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