Tuesday, March 10, 2015

Dormant pruning a young pecan graft

    This week's spring-like weather gave me the opportunity to get outside to trim some newly grafted trees. My first stop was at a small tree that had made an impressive 4 feet of new growth last summer. In the photo at right, note that the graft union is painted white and the scion is supported by a bamboo stake. The fence post is in place to hold a deer cage that protected the tree from browsing and buck rub (cage removed for the photo).
    As you can see, I made a good start on developing a strong central leader tree but the tree developed several branches near the top of the tree that, if left to grow this year, would create problems for maintaining a single dominant tree trunk. Let's take a closer look.
    Just above the graft union, some small lateral limbs have developed (photo at left). I'll be leaving these branches alone for now to help build greater leaf area on this tree. With more leaves along the lower portion of the trunk the tree develop a thicker and stronger central leader.
    My main objective in pruning this three is to define the clear central leader at the top of the tree. In the photo below you can see that the top of this tree is divided into 4 major shoots. Three of those shoots actually developed from stalked buds that sprouted into branches late last summer. I took a close up photo of two of those 3 branches (circled in red) so you can see that bark inclusions were already starting to form (yellow arrows). I pruned out all 3 branches that had formed from stalked buds.
   After pruning out the 3 side branches, I noticed that the central leader was still cover with stalked buds (photo at right). The longer shoot I pruned out with my clippers but I could snap off the shorter stalked buds with my fingers. With all stalked buds removed I was left with a central leader with prominent secondary buds.
    The photo above gives a before and after look at pruning this young grafted tree. I carved out a single central leader, removed all stalked buds, and allowed lateral branches to develop on the lower portion of the trunk (above the graft union).
    I'll need to come back to this tree  after the buds break to make directive pruning cuts to maintain a strong central leader.