Part I. MAIN PLOTS 



This section reports on applications of various combinations of cultural 

 practices known to govern the form of young balsam fir to be marketed as 

 Christmas trees. The primary objective of treatment was to test alternatives in 

 both leader and lateral branch growth control, in attempts to produce a more 

 saleable tree. The trees used in the study were native balsam fir, initially 

 averaging four feet in height, in both natural (volunteer) and planted stands at 

 three locations in New Hampshire (Coos, Grafton and Merrimack counties). At 

 each location 225 trees were treated employing a factorial arrangement of 9 

 leader treatments x 5 lateral treatments, followed in 1966 with 5 fertilizer 

 treatments. The work was initiated in the spring of 1964 with annual 

 measurements terminated in the fall of 1966. Both lateral and terminal 

 treatments were imposed in the spring and the fall. Thus there was a complex 

 interaction of three general categories of treatments (leader treatment; lateral 

 treatment; and fertilizer), replicated at the three locations in a randomized block 

 design. 



A. Explanation of Treatments 



The treatments applied included most that appeared promising from informal 

 field experimentation and local practice such as tip pruning to control terminal 

 length to forestall "spindly" tree appearance. This experiment did not, however, 

 test basal pruning to slow terminal growth because of the small size of the 

 trees. Spring treatments were applied in late June or early July (during 

 succulent growth) while fall treatments were applied in September or October 

 after growth had "hardened off. Treatments are summarized as follows: 



Terminal treatments 



Tip prune, both at 45° and at 90°, either in the spring or fall. 



Maleic hydrazide (a growth inhibitor), either spring or fall. 

 Root prune, either spring or fall. 



Control (no treatment). 

 Lateral treatments 



Clip, either spring or fall. 



Shear, either spring or fall. 



Control. 

 Fertilizer application (delayed until the spring of the third year) 



Nitrogen = N 



Phosphorus = P 



Potassium = K 



Complete = NPK 



Control. 



