Dominant and codominant trees of good and fair vigor are the source of nearly all 

 the Christmas trees in thickets. Crown deterioration in the intermediate and suppressed 

 trees is apparently severe enough to preclude their use for Christmas trees initially 

 or in any reasonable period of time after that. 



The Christmas tree grower's objectives largely dictate his choice of thinning. 

 Heavy thinnings produce the most Christmas trees initially but light to moderate fre- 

 quent thinnings produce more trees in subsequent harvests as well as maintain stands 

 with a greater potential for future production. In thinning, badly deformed Douglas- 

 fir trees, as well as trees of all other species, should be removed. All merchantable 

 trees that appear to have reached their maximum development in quality and size should 

 be harvested annually. 



In summary, Christmas tree growers utilizing natural stands of Douglas-fir must 

 recognize that they deal with extremely heterogeneous tree populations. Prescriptions 

 must be based upon sound biological and economic principles applicable to each stand 

 and individual tree. Culture techniques for Douglas-fir have been fairly well described 

 (Wellner and Roe 1947, Burlison and Pitkin 1962, Douglass 1967), but the "professional 

 touch" still will be needed to successfully prescribe the best combination of these 

 techniques for optimizing Christmas tree production. 



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