Year 3 - Summer Training and Pruning 



As in the previous two summers, special attention 

 must be paid to eliminate overly vigorous fruiting 

 branches. In addition, the vigor of the top of the tree 

 must be controlled. One of the easiest methods of 

 controlling top vigor is to let the leader bend over above 

 the point of central leader support with the weight of 

 cropping. Later, the portion of the central leader above 

 the support that has become pendulant is removed 

 entirely. This process will likely be repeated in subse- 

 quent years. It is important to remove strong upright 

 growth at the top of the tree; this growth can interfere 

 with fruit bud formation in the bottom poilion of the 

 tree. 



Year 4 — Dormant Pruning 



The lower scaffolds are permanent branches and 

 must eventually be shortened. Shortening to lateral 

 branches is used to contain the lower scaffold branches 

 to their allotted space. Also, the weight of the crop 

 bends the branches downward, and so branches are 

 pruned to promote a more horizontal growth habit. 

 (See Figure 2.) 



Vigorous growth is removed and replacement 

 branches selected in the upper poition of the tree. If a 

 branch has been fruited and requires replacement, an 

 angled stub is made. (See Figure 2.) A new branch will 

 emerge from adventitious buds and can then replace 

 the old branch. 



Pruning the mature vertical axis tree employs the 

 same techniques as that of the slender spindle: 



1. 



2. 



3. 



The lower permanent scaffold branches are short- 

 ened to weak lateral branches (preferably, fruiting 

 laterals) to contain their length. 

 The upper two-thirds of the canopy receive re- 

 newal pruning. Fruitinglaterals are not allowed to 

 remain in the tree for more than three or four 

 years. Constant renewal of the fruiting wood is 

 critical to keep the mature vertical axis tree pro- 

 ductive. 



Light must reach every portion of the tree. If light 

 islimiting, production will be affected. Special care 

 must be taken to keep the top of the tree weak to 

 prevent shading in the bottom section of the tree. 



Summary 



Both the slender spindle and the veilical axis train- 

 ing systems are central leader systems. There is a 

 dependence on summer pruning for tree training (limb 

 positioning) and a lack of heading into one-year-old 

 wood. Renewal pruning and limb shortening are criti- 



Figure 2. Vigorous growth is removed and re- 

 placement branches are selected in the upper 

 portion of the vertical axis tree. 



cal to the success of these systems. 



The systems differ in how the central leader is 

 handled. With the slender spindle tree, the centred 

 leader is headed into two-year-old wood (or older) to a 

 replacement lateral which is tied upward to continue 

 the central leader. In contrast, the vertical axis leader 

 is never headed, except at planting. 



Both the slender spindle and vertical axis systems 

 will produce more quickly - if handled correctly - than 

 the traditional PNW central leader system. In addition 

 to earlier production, there is the advantage of im- 

 proved labor efficiency. 



Changing to high density systems in the Pacific 

 Northwest will not be a matter of "if," but "when." 



This article was reprinted from Good Fruit 

 Grower, June, 1989. 



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10 



FruU Notes, Fall, 1989 



