Tuesday, June 23, 2015

Topworking a large pecan tree: Graft aftercare

    Last month, I showed you how I went about top-working a fairly large pecan tree. Using a hydradulic lift, I placed bark grafts on nine major limbs throughout the tree's canopy. Today, I went back to the tree and found that all nine grafts had been successful but they were buried in a profusion of brushy growth (photo at right).  Three bamboo stakes, attached at the top of the tree during grafting, were the only visible clue that I had grafted this tree 7 weeks ago.
    I moved the hydraulic lift up to the tree and immediately started trimming off all trunk sprouts below each graft. It wasn't long until I had the ground littered with green pecan shoots. Once I could see the scions, I found that each scion had at least two shoots growing from the original scion stick (photo at left). Many of the new scion shoots had already grown 18 inches in length so I decided to replace my short bird perches with longer bamboo stakes.
   Once the bamboo stake was firmly taped to the tree, I trimmed the scion down to one shoot (photo at right). I then tied that single shoot to the bamboo stake using engineer's flagging tape. I also used my knife to cut off the green grafting tape that holds the plastic bag around the scion. These grafts are growing extremely fast and I don't want the tape to girdle the scion.
   I repeated this process for all nine grafts I had made on this tree.
    Once I finished all necessary pruning and training, I moved the hydraulic lift back away from the tree to see the results of my handiwork.  In the photo at left, you can clearly see some of the grafts I made and the bamboo poles that support those grafts. If you compare this photo to the one at the top of this post, you can also see just how many trunk sprouts I had to remove.  I have left several small side limbs on this tree to provide shade for the trunk to prevent sun-scald.
     I'll need to return to this tree in 4-6 weeks. By that time, more trunk sprouts will appear and the grafts will need addition ties to the stakes. I surely don't want to lose any of these grafts to breakage in a wind storm.