Tuesday, April 29, 2014
Changing pecan cultivars by top-working
For an in-depth look at the bark grafting method I use to top-work pecan trees, check out this previous post. In today's post, I wanted to show you how I attack the top-working process while giving a few tips along the way.
kernel quality issues with Jayhawk so I decided to regraft this tree to a selection from our pecan breeding program.
My first cut was on the central leader about 18 inches above the lowest whorl of side branches. This cut is marked by the uppermost red line. I also removed a small side limb on the left side of the tree just below the cut I made on the central leader. I also removed the upward-growing portion of a lateral branch on the right side of the tree to make sure my new graft will get plenty of light. These cuts are also marked by red lines on the photo.
In this case, I was able to make the incision in the bark far enough to the right of the bud scar to avoid any potential problems. After carving the scion, I inserted it between the bark and wood of the stock and slid it into position perfectly.
I then decided to remove most of the upper portions of this tree. My first cut was to remove entire left side (larger diameter side) of the tree's forked trunk. The smoother bark and smaller diameter of the right side fork would provide a perfect grafting spot once the limb was stubbed back. Fortunately, this tree a several small, lateral branches growing out of the trunk below my pruning cuts. These branches would help shade the trunk and prevent any sunscald that might occur following such radical pruning.
The completed graft is shown below.