Canadian Forestry Journal, October, 1919 



41 



WHAT STARTS THE FOREST FIRES? 



Dry Weather and Dry Electrical Storms Given as the 



Chief Causes 



Everybody knows of the great forest fires in 

 the northwestern United States and in Western 

 Canada. What caused these fires is a question 

 many thousand people are asking. In a letter 

 to American Forestry H. H. Rutledge, acting dis- 

 trict forester for District No. 1 , which includes 

 the National Forest area of Northern Idaho and 

 Montana gives what he believes to be the 

 causes. The fires, he says, were due to a dry 

 year, the third in succession. Lightning, rail- 

 roads, campers, and brush-burning started most 

 of the 909 discovered on this forest area in 

 July. Lightning was given as the cause of 240 

 fires. Almost one-fourth were due to unknown 

 causes, and twenty-seven were incendiary. He 

 writes : 



"This is the third dry year in succession for 

 District 1. The snowfall last winter was far 

 below normal, and in many locations spring 

 precipitation was insufficient, many places hav- 

 ing been without rain for over three months. 

 High winds have prevailed quite generally for 

 some sixty days and the atmosphere has been 

 charged with electricity to such an extent that 

 dry electrical storms have been constantly oc- 

 curring. As a result the forest floor is as dry 

 as a powder-house, and because of excessive 

 transpiration the leaves of coniferous trees have 

 become so combustible as to be almost ex- 

 plosive when subject to ignition. 



"While human agencies have been responsible 

 for some of the fires this season, lightning has 

 been by far the most prolific source of trouble. 

 Dry electrical storms have started a great many 

 fires in the most inaccessible part of the forests 

 where it has been impossible to get men and 

 equipment on the ground quickly. In numerous 

 cases it has required from three to six days for 

 fire-fighters to reach a fire from the nearest 

 railway point. And when it is remembered that 

 equipment and supplies for the men must be 

 transported on pack-horses over rough moun- 

 tain trails and kept on the line at all times, the 

 difficulties of the situation will be appreciated. 

 Under these conditions it can be understood 

 readily how lightning-set fires in these remote 

 places become raging conflagrations before thr 

 fight against them can be begun. 



"Commonly fires due to preventable causes 

 are near lines of transportation and communica- 

 tion and can be discovered and suppressed be- 

 fore they assume serious proportions, but the 

 reverse is true where lightning fires occur. Not 

 infrequently in the most inaccessible mountain- 

 ous regions ten, fifteen, or twenty fires are start- 

 ed within a few minutes by a single electrical 

 disturbance. Sometimes these blazes are scat- 

 tered over quite a large extent of territory, often 

 they are close together, and before it is possible 

 to start the fight against them they coalesce and 

 form one big fire which, if the wind is blowing 

 freshly, soon reaches the tops of the trees and 

 develops into a crown fire that defies human 

 efforts to combat it so long as the wind con- 

 tinues. 



"Detailed reports on file from the several 

 national forests of the district cover the situa- 

 tion only up to the close of July 30. During 

 the night of July 31 over fifty fires were started 

 by one severe electrical storm that ran along 

 the westerly slopes of the Bitter Root Mountains 

 in Idaho forests. These fires have been merely 

 reported by wire, their extent or precise loca- 

 tions not yet having been determined by the 

 field officers. They were scattered over a ter- 

 ritory embracing roughly 4,000 square miles. 

 Does this single night's experience convey an 

 idea of what the Forest Service fire organiza- 

 tion in District 1 is contending with?" 



On July 30 there were approximately 3,300 

 fire-fighters on the line, not including rangers, 

 lookout men, smoke-chasers, and other regularly 

 employed forest officers, numbering about 1,500 

 men. 



F. C. Wilfong and his crew met with a trying 

 experience during the Selmay fire on Crooked 

 Creek on July 24. They were trapped where 

 three fires met, and their camp was burned. 

 The party saved themselves by lying in the 

 Selmay river for thirty-five minutes with wet 

 blankets over their heads. Only one of their 

 thirteen horses was lost, but the pack-saddles 

 were burned from the backs of the others. Mr. 

 Wilfong says of his experience: 



"There was no way out of it ; we were cor- 

 nered and we plunged into the water, keeping 



