Change of grade with terminal treatment when compared to the control trees 

 developed as follows: 



a. fall tip pruned trees and trees root pruned either spring and fall did not 

 grade out as well as the control trees. 



b. trees tip pruned 45° in the spring performed as well as control trees and 

 those tip pruned 90° in the spring showed a significant improvement over 

 control in grade change. 



c. maleic hydrazide fall treatment showed somewhat of an improvement 

 over control but this is meaningless when it is recalled that this treatment 

 affected neither terminal growth nor whorl branching. Maleic hydrazide spring 

 treatment matched the control trees in grade change. 



When the components of overall grade are examined, it is of interest to note 

 that fall tip pruned trees scored well in crown density but more than lost this 

 gain in symmetry and taper. The reason for a good density rating with relative 

 reduction in whorl branching is not explained, since the internodal length 

 reduction was not different from the other effective treatments. The density 

 would logically be expected to be caused by increased internodal branching or in 

 foliage characteristics such as number and length of needles. The change in 

 internodal branch rating was recorded in the experiment, but no treatment 

 significance was shown. 



In summary, if terminal control is applied, tip pruning in the spring with the 

 90° cut is favored. In Section II or Growers' Plots, more is said on terminal 

 control in conjunction with fertilizer application. After reviewing the results on 

 this related experiment a suggestion is made that perhaps terminal control can be 

 dispensed with, at least as a routine measure, when fertilizer application is a 

 standard practice. Fertilizer as recommended should improve internodal bud 

 formation and internodal branching, allowing excellent form even with long 

 internodes. 



2. Lateral Treatments 



It is important in the application of results of the lateral control work to 

 understand how shearing and clipping were interpreted and applied in this 

 experiment (Section A). 



Both fall and spring treatments as applied were highly effective in increasing 

 the numbers of lateral tips and thereby developing a fuller Christmas tree. The 

 basis for comparing treatments was the increase in number of growing tips in 

 what were the top three whorls in 1963 and the 1964-66 whorls combining, 

 in other words, the changes in number of tips in the whorls dating from 1961 

 through 1966. 



In the 3 year period, the control trees increased by 16.1 tips per tree. 

 Treatments added the following tips: spring shearing, 42.2; fall clipping 37.5; 

 spring clipping 35.9; and fall shearing 33.5. Among the lateral treatments, the 

 most effective treatment used was therefore spring shearing. There was no 

 significant difference in the experiment between spring and fall clippings or 

 spring clipping and fall shearing. 



