Monday, May 21, 2012

Directive pruning young trees

     Grafting a pecan tree is only the first step in developing a strong, nut-bearing tree. Directive pruning is essential for developing a new graft into a tree with a strong straight trunk. Last week we worked on some of the trees we grafted last summer (photo at right).
     Left on their own, young pecan trees will develop multiple leaders and a bushy top. In this photo, you can see at least three new shoots growing in competition to be the central leader.
   Once I remove all the suckers growing below the graft, I move to the top of the tree and select the one new shoot to become the central leader.  You usually find 3 to 4 strong shoots all growing from the top 2 to 3 inches of last year's wood. By choosing the lowest of the strong upright shoots to become my new central leader, I can make a single pruning cut and remove all competing shoots (photo at left).
      Once the cut is made, you can clearly see that I have a new single central leader. Now this shoot will receive all the tree's energy and grow rapidly in both height and girth.
    To make sure I don't loose the tender growth of my new central leader to wind or bird damage, I tie the new shoot to a bamboo stake using plant tie ribbon.  Before leaving this tree, I pinch off the growing points of all lateral branches below the central leader. This slows down the growth of the laterals and focuses all of the tree's resources on growing a strong straight trunk.