some development of yellow-poplar seedlings early in the growing season 

 before strong competition from other plants develops. Logging in the 

 spring and early summer results in late summer seedlings, which do not 

 survive well, and competing vegetation is able to get a head start on seed- 

 lings originating the following year. 



This restriction on time of logging becomes less important in areas where 

 the yellow-poplar seed source is extremely plentiful and where site condi- 

 tions are ideal for this species. However, where the situation is not so 

 favorable for yellow-poplar, control of time of logging might provide 

 the needed advantage. 



— GEORGE R. TRIMBLE, JR. 



Project Leader, Timber and Watershed Laboratory 

 Northeastern Forest Experiment Station 

 Forest Service, U.S. Department of Agriculture 



Parsons, W. Va. 



— E. H. TRYON 



Professor of Silviculture 

 West Virginia University 

 Morgantown, West Virginia 



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