ASPEN AS A TEMPORARY EOREST TYPE 303 



economic viewpoint the tendency toward a reversion to conifers is de- 

 sirable, management must be so applied as to favor them by moderate 

 cuttings to maintain an optimum sheltering canopy rather than a clean 

 cutting system that is so favorable to aspen, but which is not conducive 

 to the establishment of the conifers. Planting under aspen is an en- 

 tirely natural process and will undoubtedly prove successful with Doug- 

 las fir when the methods of handling that rather difficult species are 

 properly worked out. While it is impossible at this time to state 

 whether the perpetuation of the aspen type or its reversion to conif- 

 erous forest is most desirable from the standpoint of forest manage- 

 ment, it seems probable that at least the poorer aspen sites will be 

 turned over to the conifers, as they alone yield material which is mer- 

 chantable at the present time on such sites. Since aspen is so clearly 

 temporary, such a change can be made either by assisting natural ten- 

 dencies or by artificial means with no fear of ultimate failure ; for what- 

 ever the economic relations of the aspen and conifers (white fir and 

 Douglas fir in particular) may be, their ecological relation is unmis- 

 takable and is essentially the same here as elsewliere throughout the 

 range of aspen. 



