stalked buds from rapidly growing young trees to encourage the growth of a strong central leader tree. The photo at right shows the terminal portion of a tree I grafted this past spring. Note that the primary buds in each leaf axil have already formed a long stalked bud. By removing all these primary buds near the apex of the tree, I can force the tree to remain focused on growing a single central leader. Pruning out stalked primary buds effectively delays the tree from developing lateral branches in the pruned area for 3-4 weeks. This allows the central leader to grow taller, staying well above later developing lateral branches.
These secondary buds were fully sessile when they were formed. But at this point in time, the secondary buds are pushing out to grow new lateral branches. And since these new shoots are forming about 2 feet below the central leader's terminal, you should let them grow out.
The art of young tree training is an act of making sure a tree achieves balance between growth of the central leader and the development wide-angled lateral branches. Allowing secondary buds to grow and produce laterals is an important part of that art.
Thursday, July 30, 2015
Wednesday, July 29, 2015
At this point in time we are between generations. The second summer flight of fall webworm moths usually starts in early to mid-August. Judging from the number of first generation colonies I've seen up and down the road, the second generation should be ever larger. Fortunately, we will be spraying our trees for stinkbugs and pecan weevils during the month of August and these sprays will keep the second generation out of our pecan grove.
Thursday, July 23, 2015
|16 July 2015|
In the photo above, I've arranged 5 cultivars in order of the expected ripening date this fall. Faith will split shuck in late September while Stuart won't mature until late October.
|16 August 2015|
What does all this mean? It means that USDA 75-8-5 will ripen in late September at our location. Surecrop, Lakota, and Gardner will ripen in early October. City Park will be the latest to ripen sometime in mid-October.
Monday, July 20, 2015
This is a tree that never developed a good balance between a strong central leader and lower lateral branches. I placed a 5 foot ladder in the photo to give you an idea how tall this tree actually is. The tree was grafted at about 3 feet high (the union is marked with white paint). The graft grew strongly but failed to sprout lateral branches along the leader in an area 3-4 feet above the graft union. It was this lack of lower lateral branch formation that ultimately caused the tree to become top heavy and start to bend over.
Friday, July 17, 2015
I collected several nuts from 75-8-5 and placed them in a plastic zip-lock bag to bring inside to photograph. I especially wanted to look at a scab lesion up close, using a dissecting microscope, to see if I could see the scab fungus sporulate. I held the nuts in the plastic bag overnight to provide the high humidity conditions needed to promote the development of pecan scab spores.
In response to the high humidity, that formed inside the plastic bag, the scab fungus developed structures known as conidiophores or translucent stalks that stick up from the surface of the lesion. These conidiophores give this scab lesion its fuzzy appearance.
On the ends of each conidiophore, a chain of oval-shaped conidia form. These conidia are the spores are released into the air, spreading the fungus throughout the orchard.
After this simple experiment in forcing sporulation from a scab lesion, I now know how quickly and easily scab can create new conidiophores and conidia out in the field. I am more than ever convinced that grafting scab resistant pecan cultivars is the best way to fight this disease
Wednesday, July 15, 2015
|Pawnee, 15 July 2015|
|Mandan, 15 July 2015|
Friday, July 10, 2015
Tuesday, July 7, 2015