Friday, July 5, 2013

Time for new graft training

    Now is a good time to start training your successful grafts. Today, I worked on a couple of bark grafts including the tree pictured at right. After removing the deer cage, I cut off all sprouts growing from the trunk below the graft union. I next turned my attention to the shoots growing from the scion. I had left 2 buds on the scion when I grafted this tree and both buds had sprouted and were growing vigorously.
    In the photo at left, you can see that both scion shoots are about the same size in diameter.  I could choose to keep either one of these shoots to be my new central leader, but the straighter growth of the shoot on the right gives it a slight edge.  I then cut out the shoot on the left.
    With just one cut, I have established a new central leader for this tree (photo at right). Now all of the tree's energy will be focused into growing the scion's single remaining shoot.
    Like all vigorously growing pecan shoots, the shoot that I kept to become my new central leader was already producing stalked buds (photo at left). To prevent these stalked buds from growing into branches that form serious bark inclusions, I broke off every one of them. Breaking off stalked buds will also help preserve the dominance of the new central leader.
    My next step was to cut off the grafting tape that holds the plastic bag tightly around the scion. The scion on this bark graft should grow rapidly in diameter this summer and I don't want the tape to girdle the scion. After cutting and removing this small piece of tape, I will leave the rest of the graft wrappings in place for now.
    Next, I replaced the bird perch on the graft with a much longer bamboo stalk. I used electrical tape to attach the bamboo to the trunk of the stock, then used flagging tape to tie the new growth to the stake (photo at left). Bark grafts are easily damaged in the wind, so tying the new growth to a stake is a critical part of the graft training process. My final step, was to place the deer cage back over the tree. (No browsing deer is going to ruin this graft!)