CONCLUSIONS AND RECOMMENDATIONS 



Cultural treatments can increase Christmas tree production in natural stands of 

 Douglas-fir. The results from this study should encourage the use of stump culture 

 treatments, discount the value of single pruning treatments on many Christmas tree sites, 

 but encourage frequent, light to moderate thinnings in thickets. 



Stump culture produced large, high quality Christmas trees rapidly. In this study, 

 a higher percentage of premium quality trees were produced from stump culture than from 

 any other treatment. Of the stumps treated to feature branch turnups, 60 percent pro- 

 duced merchantable trees within the 10-year period after the original tree was cut. 

 Treatment to favor adventitious shoots also produced Christmas trees, but treatment to 

 favor branch turnups outproduced them 3 1/2 to 1. This contrasts with the coast form 

 of Douglas-fir in the Pacific Northwest where adventitious shoots appear to be more 

 productive than branch turnups. 2 



Treatments favoring either turnups or shoots produce Christmas trees of nearly 

 equal quality, but trees from turnups reach larger sizes earlier than do trees from 

 shoots. About half of the merchantable trees from the stump treatments in this study 

 were premium- or standard-grade, but one-third of the turnup trees reached the 10- and 

 12-foot class while none of the shoot trees reached these sizes. 



The manager apparently has a fair amount of latitude in choosing the time to treat 

 stumps. No differences could be detected in this study between stumps treated the same 

 time as the original tree was cut or stumps treated as much as 3 years later. However, 

 to assure that stump vigor is maintained, some growers feel that treatment should be 

 delayed a year or more. 



The logic behind stump treatment is sound. The inherent genetic characteristics 

 that determined the quality of the original tree--for example, branch angle and needle 

 color and density--can be relied upon to provide the same qualities in the turnups or 

 shoots. Thus, the stumps not only produce Christmas trees sooner than could be grown 

 from planted stock, but their quality is also predictable. 



Stumps from open-grown trees should be treated for branch turnups. Such a stump 

 can produce a Christmas tree, and in many cases, several trees before any comparable 

 trees could be grown from natural or planted seedlings. The following can be recom- 

 mended as guidelines: 



1. Treat stumps of trees that have demonstrated desirable Christmas tree 

 characteristics . 



2. Cut the original tree above the second or third whorl of vigorous live branches. 



3. Reserve as many as six or seven major branches to sustain the vigor of the 

 stump. Favor two or more of these branches on alternate sides of the stump for turnup 

 trees by removing branches that are competing with them for space. By favoring more 

 than one turnup tree at a time, excessive leader growth can be more easily controlled. 



4. Turnup trees may be basal pruned to maintain satisfactory internode length 

 because they often grow too fast. 



"^Personal communication with Bernard S. Douglass, State and Private Forestry, 

 Region 6, USDA Forest Service. 



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