ably less than in 1912. This indicates very plainly, Mr. Graves 

 says, that the public is awakening to the need of spark ar- 

 resters and care with engines in the woods. 



Causes of Increase in Fires. 



Looking for the reason of the increase in number of fires, 

 the forester finds three main causes: 



First of all, the unprecedented electric storms which swept 

 the whole state of California at the end of a long dry season 

 and set, almost simultaneously, about 700 fires. The 804 fires 

 set by lightning in California formed nearly 50 per cent of 

 the 1,628 fires on the national forests of the state from all 

 causes, and 1 were more than half of the 1,571 lightning-set 

 fires in all the 21 states reporting. 



In the second place, there were 757 fires which started out- 

 side the forests, of which 644 were stopped by the govern- 

 ment's fire fighters before they reached the forest boundaries, 

 as against 424 which started on outside areas in 1912. How- 

 ever, the proportion of such fires to all those which the serv- 

 ice battled with was about the same for 1912 and 1913. 



Incendiary Fires. 



The other increased cause of fires was incendiarism, but 

 this increase was confined to three states, Arkansas, Cali- 

 fornia, and Oregon, all others showing a marked decrease, 

 cording to forest officers, a growing carefulness on the part 

 fornia, and 142 in Oregon, where two brothers were known 

 to have set 72 on one forest alone. These two and other in- 

 cendiaries were, of course, severely dealt with by the law. 

 On the Arkansas forest, too, it has been assumed that the 

 351 fires classed under the general heading of "origin un- 

 known" were mainly incendiary. In California the incendiary 

 fires are largely attributable to what is known as the "light- 

 burning theory," which advances the argument that forests 

 should be burned over frequently to prevent the accumulation 

 of debris. The forest service considers this a pernicious the- 

 ory because it scars the standing timber and thus reduces its 



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