Monday, January 30, 2017

Dormant pecan tree pruning

   I took advantage of some mild winter weather to prune some of my young pecan trees. This year I continued the process of trimming limbs to eventually create a tree with at least 8 feet of clear trunk. But remember,  lower limb removal  is a multi-year task. This year, I'll be trimming off 2 limbs from the tree pictured at right.Lets take a closer look.
    In pruning this tree, I will concentrate on two areas on the main trunk (photo at right). The lowest whorl of branches was located at about 3 feet above the ground (arrow labeled #1). You can see a pruning wound and a single branch left on this section of the main stem.  Higher up along the stem is a second whorl of branches (arrow labeled #2) with 3 branches growing out from the trunk. This year, I will remove the lowest branch (#1) and one branch from the second whorl (#2).

   Before I show you new pruning cuts, I thought it would be interesting to show you how a tree heals over previously made pruning cuts (photos above). Three branches originally grew from the lowest whorl of branches. Walking around the tree I could see the scars where I pruned off limbs in 2015 and 2016. The 2015 pruning wound has grown over completely by the smooth bark of callus tissue. A deep split in the bark marks the location of the pruned off limb.  The 2016 pruning scar demonstrates how a tree seals over a pruning wound. Callus tissue grows fastest to the right and left of the wound. Callus forms to a lesser extent below the pruning wound but barely grows above the cut. By the end of the 2017 growing season, the pruning cut I made in 2016 will be fully enclosed just like the 2015 pruning cut.       

   The first pruning cut I made this year was to remove the lowest limb left on this tree. In the photo at right, you can easily see last year's pruning wound but this year's cut is a little more difficult to see. Along the right edge of the trunk note that I made a angled cut to remove the low limb.

   I then moved up to the second whorl of branches. In the photo at left, note that there are three branches growing from this section of the trunk. During last year's pruning effort I had removed a branch from this area. The pruning wound is marked by an orange arrow on the photo. This year I removed another limb from this area (red line). I choose this limb to prune because it was located on the opposite side of the tree from the limb I had just cut from lower down on the trunk.

    Two cuts with a chainsaw and I was done pruning this tree for 2017. Two low limbs remain on this tree. I'll remove one in 2018 and the last one in 2019. One these limbs are removed I should have 8 eight of clear straight trunk.