THE RELATION OF FORESTS AND FOREST FIRES 399 



of square miles in the Rocky Mountain region by the action of 

 fire. It is a fact that this thin-barked tree, which succumbs 

 with the utmost readiness to fire, is gaining ground by the action 

 of its enemy, replacing over great areas thick-barked species like 



\ IIKI'.II SKKIU.INi; III-' 



l.ONGLEAF PINE — SHOWING PROTECTING NATURAL GROWTH OF 

 ITS NEEDLES 



the red fir and the western larch. The device to which this 

 curious result is due is similar to that of Pinus attenuata, to which 

 John Muir long since called attention.* It consists in the hoard- 

 ing for several years of the ripe seeds in the cones. Fire rarely 



*See The Mountains of California, p. 151. 



