Thursday, June 29, 2017
Three weeks ago I forced new growth from the scion by pruning off all bark sprouts growing below the graft union. But now, you can see new bark sprouts have formed (note leaves with reddish coloration).
To prevent the grafting tape from girdling the scion, I'll remove the tape (labeled C) but leave the rest of the graft wraps on the tree at this time.
deer cage back over the tree to prevent browsing damage.
In about 3 weeks, this tree will need more attention. I'll need to prune off any new stump sprouts, remove stalked buds that develop on new growth and tie the new shoot to the stake as the tree grows in height.
Tuesday, June 27, 2017
A quick look at the Giles nut cluster reveals just the smallest hint of scab infection, a very small black lesion on the upper left side nut. However, if you look at the leaf below the nut cluster you will numerous scab lesions appearing as black irregularly shaped spots.
With plenty of scab spores up in the tree (coming from leaf lesions) we'll need a good fungicide program to protect the nut crop. We've sprayed once but additional sprays will be needed.
Friday, June 23, 2017
To make sure the leader would develop into a strong, upright-growing trunk, I needed to prune off all the side branches in this portion of the tree.
In pruning the top of this tree, I removed both the 2016 and 2017 crow's feet (photo at left). Suddenly, I've reclaimed a single central leader.
My biggest problem in making these pruning cuts is that I needed my 8 foot orchard ladder for every cut. I guess that is the price I pay for grafting onto a fairly large rootstock tree and witnessing 5-7 feet of new growth each year.
Tuesday, June 20, 2017
The photo at right is a Kanza graft I made this spring. Hanging down over the plastic bag, that I use to wrap the graft union, are catkins produced by the scion. At the very top of the scion's new shoot growth is a cluster of female flowers.
Whenever I see pistillate flowers forming on a new graft I usually pinch them off immediately. At this point in the tree's life, I want to encourage maximum vegetative growth. Female flower production on a new graft only serves to slow shoot growth.
Monday, June 19, 2017
|Spraying pecans (view from the tractor seat)|
Read any chemical label and you'll find the rates of application given in amount of product per acre. Our sprayer has a 500 gallon tank or enough water to cover 5 acres. To determine the amount of product to be added to the spray tank, I just simply multiply the per acre rate by 5. The recommended application rate is for Quilt is 14 oz. per acre. In filling our sprayer, I added 70 oz of Quilt to the spray tank.
One word of advice abound spraying fungicides. Good disease is only achievable when the fungicide covers all plant surfaces. To get good spray coverage I always spray each tree from both sides. You should not assume that your air-blast sprayer is powerful enough to penetrate the entire canopy from just one side of the tree.
Friday, June 16, 2017
Three times per week we scout our orchard for signs of insect damage (photo at right). The results of each of our scouting runs can be found by clicking on the Pecan Nut Casebearer tab (The tab is located just below below this blog's header). We have yet to find more than 1% damage.
In a normal year, we apply a fungicide to control pecan scab at the same time we apply an insecticide to control casebearer. Its now mid-June and we still haven't applied any pest control chemicals. So starting next Monday (June 19th) we are going to start spraying a fungicide to protect our pecans from scab. If the casebearer population stays low, we won't be including an insecticide with this spray.
In late June, we might see fall webworm or walnut caterpillar move into the grove. If these insects appear, we will include an insecticide in the spray tank when we make our second scab spray (around July 1).
Friday, June 9, 2017
The ladder in the photo is 6 feet tall which gives you a good idea how fast this tree has grown. The graft union is about 2 feet from the ground and is painted white. Last year (the same year I grafted the tree), I trained the tree to a single central leader. The new graft responded by putting on over 6 feet of new growth in a single growing season. This Spring, buds all along the central leader broke and new shoots began to develop. However, growth has been most aggressive at the top of the tree.
My first step in pruning this tree was to climb the ladder and search out the very top of last year's growth (photo at left). I was amazed by how many new shoots had developed at the top of the tree. Not only did primary buds break and start growing into new shoots but many shoots had grown from secondary buds. Its no wonder this tree was looking so top heavy.
After parting the foliage, I identified one upward growing shoot to become my central leader. At that point, I removed all competing shoots at the top of the tree. Here's where I use the first part of the 2-foot rule. Measuring down from the apex of my new central leader I pruned off all lateral shoots within the top 2 feet.
To slow the growth of lateral branches and encourage diameter growth on both trunk and branches, I employed the second part of the 2-foot rule. All lateral branches were tip pruned to two feet in length.
For more detailed information on training young trees and the 2-foot rule click HERE to begin reading my six part series.
Thursday, June 1, 2017
In the photos below, you will see seven successfully grafted trees before (left) and after (right) pruning. As you look over the photos, take note of a few things. First, the sprouts that are growing from the stock below the graft union have leaves with a reddish coloration. In sharp contrast, the leaves growing from Kanza scions are light green in color. Red pigmentation of emerging leaves is characteristic of juvenile pecan tissue. The leaves growing from the Kanza scions originate from sexually mature tissues in the bud stick and are fully green.
The second thing I noticed about these trees is that vigorously growing stump sprouts seem to inhibit the growth of buds on the scion. Trees 5 and 6 had so much rapid shoot growth coming from below the graft that the buds on the scion were barely sprouting. And remember, all these grafts were made on the same day using Kanza scions.
The differences in scion growth we see in the field are most certainly due to the natural variation in seedling rootstocks. Some rootstock trees will callus over a scion faster than others. Better and faster callusing will allow the scion greater access the the rootstock's energy reserves resulting in enhanced scion growth.
Some rootstocks seem to produce more stump sprouts than others. Rapidly growing shoots produce plant horomones that retard the growth of other buds on the tree. This is why it is so important to prune off stump sprouts.
I grafted over 100 trees this year. Looks like I'll spend a few more days pruning off stump sprouts.