FOREST FIRES 147 



in this way close utilization may considerably reduce or render 

 unnecessary the cost of brush burning. 



While the conditions are such that measures of this sort are 

 not always feasible, it may readily be seen that if this inflam- 

 mable material is cleared from certain belts in the forest it 

 would be comparatively easy to check a fire. Belts of this kind 

 are called fire lines. 



FIRE LINES. 



A fire line or fire lane is a strip kept free from inflammable 

 material, so that a fire will either go out of itself on reaching 

 it, or can easily be extinguished at this line by a crew of fire 

 fighters. 



Fire lines may be of various widths and made in different ways 

 according to the forest and kinds of fire likely to occur. Investi- 

 gation of the Vermont fires of 1908 showed that crown fires 

 occurred only in coniferous forests, and that practically all of 

 the worst fires started in slash made by lumbermen. One 

 effective form of fire line could, therefore, be made by burning 

 all the tops and dead-and-down timber and removing all conifers 

 from the strip in question. 



Of course surface fires would cross such a strip, if unprotected, 

 upon the leaves and underbrush. It would, therefore, be well 

 to cut from a narrow strip all growth of trees and brush and to 

 burn the leaves annually. 



This can be made still more effective by grubbing out the 

 stumps and plowing a few furrows. 



As an ideal fire line for mixed forests, we would suggest the 

 following: 



(a) A strip one hundred feet wide from which all coniferous 

 trees and all underbrush and all dead-and-down timber are re- 

 moved to prevent crown fires. 



(b) One-third of this or a strip thirty-three feet wide to be 

 annually burned over to prevent surface fires. 



(c) A portion of this or a strip six to ten feet wide, to be 

 grubbed out, and, if possible, plowed to prevent ground fires. 



