One of the most common pruning mistakes pecan growers make involves removing lower limbs. It seems like folks get in a hurry to trim off all lower limbs with the idea they can force the tree to grow taller and faster. But pruning too severely can actually slow overall tree growth, enhance the development of
stalked buds (which create narrow branch crotches) and cause sun scald damage to the trunk.
While enjoying the sunshine and warm temperatures this past weekend, I spent some time pruning some of my pecan trees. The photo at right shows one of my Kanza trees. The tree has good form and requires no major corrective pruning. However, some of the lower limbs are just too low, making mowing around the tree with a tractor difficult. But when I prune lower limbs I take a "go-slow" approach. Lets take a closer look.
The photo at left shows the lower portion of my Kanza tree's trunk. Four nicely attached limbs radiate from the central leader but they are all only 5 to 6 feet above ground level. All of these limbs will need be removed in time but not all this year.
Last year I removed a single limb from this tree and the resulting wound has almost completely healed over (note wound just above the white marking paint). This year I'll prune another low limb. Making the decision as to which limb to remove was not that difficult. I choose to remove the limb pointing to the left because it had another limb just above that would help fill its place in the tree's canopy.
When removing a low limb I use my chainsaw to undercut the limb just outside the branch collar (photo at right). Making this cut first will prevent possible bark tearing as I prune the limb off the tree.
Next I use a plunge cut to remove the limb without damaging the trunk. I start the cut from the side of the branch leading with the lower half of the saw blade's tip (photo at left). Once the saw starts to feed into the branch, I complete the cut by pushing the blade through the branch and them downward. In making the plunge cut, I always try to align the blade at the same angle as the original undercut. This way I create a nice smooth wound.
Once the cut is completed (photo at right), I don't treat the wound with any kind of tree would dressing. A healthy tree will heal over a wound of this size in just a couple of years. Just look how last year's wound has nearly closed over since last March.
The above photos were taken before and after pruning. Note that the canopy of this Kanza tree has hardly changed. That's exactly why I take the "go slow" approach. By keeping the canopy of this tree largely intact I preserved both leaf area and nut bearing potential. After all, its the nuts I'm after. As this tree continues to grow in size, I'll keep removing low limbs at the rate of one per year until I achieve at least 8 feet of clear trunk.
