86 THE PRINCIPLES OF HANDLING WOODLANDS 



tical considerations of logging require a concentration of 

 cutting. 



3. Where the trees are so large that their removal 

 after reproduction is established would result in destruc- 

 tion of the young growth. 



4. Where the trees are so large and valuable that their 

 retention for seed would involve a greater investment 

 than artificial planting. 



5. Where a clearing is necessary to remove trees of 

 undesirable form or poor species, in order to establish 

 artificially better species. 



6. Where a clearing is necessary to secure good nat- 

 ural reproduction of some species which cannot thrive 

 under shelter. 



Frequently a clear-cutting is required by a combina- 

 tion of the conditions just enumerated. Thus, for exam- 

 ple, in the Cascade Mountains of Washington a stand of 

 red fir, cedar, and hemlock from 400 to 800 years old, 

 with trees from 4 to 10 feet in diameter, and from 200 

 to 250 feet high, presents the conditions of overmatu- 

 rity of all trees, great expense of logging, and the im- 

 possibility of removing trees without injury to young 

 growth. It is obvious that under such conditions a 

 clear-cutting is necessary. 



Disadvantages of a Clear-Cutting 



There are certain disadvantages attendant on the clear- 

 cutting system, as follows: 



1. In any clear-cutting system there is necessarily ;t 



