was a simple visual rating scheme, subjectively judging if the 1967 color appeared 

 poorer, the same or better than the 1966 foliage (this was to give an indication 

 of "hold-over" on color change into the second fall after first year spring 

 fertilizing). The comparison made it clear that the 1967 foliage of N and 

 complete (NPK) treated trees had regressed to a significantly "poorer" visual 

 reaction, whereas the control and other treatment trees had not changed 

 significantly from their 1966 appearance. The color change was not sufficiently 

 great as to justify fertilizing every year. Another conclusion was that the color 

 had started to "regress" nearer to 1965 with both high and low levels of N and 

 complete (NPK) fertilizers. Holdover in color improvement during the second 

 year by heavier fertilizer application was not substantiated in the Growers' 

 experiment . 



C. Conclusions of Growers' Plots 



The results of the Growers' experiment argues strongly for use of complete 

 (NPK) fertilizer to shorten rotations of balsam fir Christmas trees and still 

 produce trees of comparable form. Fertilizers if applied in late May or early 

 June in northern New England will result in marked tree color improvement for 

 early fall harvest. It is believed that fertilizers should be applied at low 

 levels 1 and not be done on an annual basis. Application every other year would 

 appear maximum, with further study needed to see whether this can be extended 

 without significant fall-off in growth rate. 



The commercial grower can refer to data on the soils encountered in the 

 Growers' Plots, presented in Table 5, and compare it to that on his own lands. 

 He should also relate the size of his particular trees to those in the study in ad- 

 justing fertilizer dosages. The efficiency of his method of application (the 

 fertilizer reaching tree roots) as compared to the hand method employed in the 

 experiment is another major consideration before determining the poundage of 

 fertilizer to apply in any specific situation. 



To relate fertilizing practice with nutrient uptake, the foliar analyses of 

 control trees on the Growers' Plots making up part of Section III on Foliar 

 Analysis was conducted. 



Part III. FOLIAR ANALYSIS OF BALSAM FIR 



A. Growers Plots 



During the development of this study the potential of foliar analysis as a 

 means of pinpointing nutritional deficiencies in balsam fir Christmas trees 

 prompted preliminary work in this field. The work was limited to chemical 

 analysis of foliage of some of the control trees in the Growers' study and on the 

 Main plots, and of selected trees at other locations. All foliar analyses were 



Previously, low level complete (NPK) or Comp. low was defined as 0.10 lbs of elemental 

 nitrogen, 0.11 lbs of elemental phosphorus and 0.12 lbs of elemental potassium per 4 to 5 

 foot balsam fir tree, or 1.1 lbs of a 10-10-10 NPK fertilizer per tree. 



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