Black Spots on the Kernel

It is not until you crack open a pecan that you discover that stink bugs have been feeding in your orchard. In the photo at left the large, sunken black spots on the kernel were caused by one of several large bugs, including the southern green stinkbug, the brown stinkbug, and the leaf-footed bug. We commonly lump all these insects together and call the damage they create, stink bug damage. The black spots are created when stink bugs feed on pecans when nuts are filling their kernels (mid to late August). This group of insects have a needle like mouth part that can pass through the shuck and hardened-shell to get to the kernel. As the insect feeds, it secretes digestive fluids into the nut that actually breaks down some of the kernel, so the insect can feed on a kind of pecan slurpee. These digestive juices are what cause the black spot on the kernel.
     For those of you that are picking out pecans for your family, be sure to break out these black spots and discard them. The black spots are bitter and will ruin a good pecan pie.

KSU-OF1 to be named 'Oswego'

     We've been looking at a 'Greenriver' seedling,  KSU-OF1, for several years now. This year, during our harvest tour, everyone could see the major difference between the original 'Greenriver' cultivar and its progeny--The KSU-OF1 clone had twice the yield as its parent. Although 'Greenriver' is a scab resistant cultivar, the main drawback for grafting 'Greenriver' has always been that the trees are somewhat shy nut producers. In sharp contrast, producing great nut crops is one of the best attributes of  KSU-OF1 (photo at right).
     During harvest, I picked up nuts from both 'Greenriver' and KSU-OF1 and I had trouble telling them apart. Both shells and kernels looked identical. Oh, boy! Could these 2 trees be that same cultivar? I think not. We have 'Greenriver' and KSU-OF1 grafted in the same cultivar trial block on the same seedling rootstock and the yield difference between the 2 clones was consistent--every KSU-OF1 tree had far more nuts than the 'Greenriver' trees. The yields were so different you could see it by just looking at the trees. Although closely related,  KSU-OF1 is a definite improvement over 'Greenriver'.
     As I told the folks at the Harvest Tour, I've decided on a name for KSU-OF1. This new pecan cultivar will be called 'Oswego'. I chose this name to honor one of the little towns in SE Kansas that is known for pecan production. You might remember I started this tradition for naming new pecan cultivars  when I named 'Chetopa', originally tested under the name KS112,

Pickin' pecans

     We had the Chetopa third grade class come out to the Pecan Field for a lesson on pecan growing and pecan harvest. The kids love to feel the ground shake when I use our tree shaker on a tree I've selected for them to harvest. It is amazing to see all those squirmy 9-year-old kids get down on the ground and concentrate on finding pecans amongst the leaves (Photo at right).
     These same kids went up to my wife's apple orchard later that day to learn about apple harvest. They returned to school loaded down with pecans and apples. This week they will be making apple crisp with the produce they picked themselves. 
    As nut growers, we all have a duty to teach the children in our communities how their food is grown. Just think of it as investing in future customers.

Kanza, another great crop in 2010

2010 Kanza crop

     I remember my first days when I came to Kansas 30 years ago. As a young man just getting my feet wet in the pecan business, I decided to travel to OK and and TX to learn about pecans from some of the leaders in the field. Down in Oklahoma, I listened to Cat Taylor tell a group of growers that the best pecan cultivars for Oklahoma had been found--'Mohawk' and 'Maramec', no question about it.. In Texas, George Ray McEachern was adamant that 'Cheyenne' was the perfect pecan for Texas.
    With the passage of time, 'Mohawk', 'Maramec' and 'Cheyenne' have all developed serious problems that make their status as "best cultivars to plant" questionable. 'Mohawk' trees have been cut down by the thousands because of severe over production problems. Maramec's problem is just the opposite--light yields make this a difficult tree to keep profitable. Down in Texas, 'Cheyenne' seems to be the most attractive cultivar for aphids driving production costs through the roof.
     What I've learned from my colleagues is that there has never been or probably never will be the perfect pecan cultivar for growers to graft. With that said, every year I see 'Kanza' produce another crop of nuts (see photo above), I get more and more impressed with this cultivar. 'Kanza' ticks all the boxes for me--Scab resistant, annual production, good tree structure, outstanding kernel color and quality, and excellent shell out (mostly halves). Is 'Kanza' the perfect cultivar for northern pecan growers? I guess we'll see in 30 years.

Pawnee back in action!

The December 2007 ice storm left our Pawnee trees in shambles. Of all the cultivars we have under test at the Pecan Field, Pawnee was one of the most brittle under the weight of the ice (photo at right). Our trees required a massive amount of pruning following the storm and many trees were broken down to the point we had only the trunk and a few stumps of lateral branches left.

This fall is the first year the damaged trees have produced a crop. We knew when we pruned our Pawnee trees that the precocity of this cultivar would help us get back into production fairly quickly. Looks like the crop of Pawnee nuts (photo at right) we harvested today will help us pay some bills at the Pecan Field!

Harvest!

    The pecan harvest season has arrived and we are looking forward to harvesting an above average crop this year. I love this time of year. Cool days and crisp mornings only seem to heighten the excitement of the harvest season.

     I was out talking photos of different pecan cultivars when I spotted a Pawnee nut suspended from the shuck (photo at left). I like this kind of photo because it portraits the action of nuts falling out of the husk when the nuts are fully ripe. But this photo also tells the story of the importance the shuck to nut development. Look carefully at the fibers than are holding this Pawnee nut suspended from the shuck. These fibers are part of the vascular system that lines the inside of the shuck and are attached to the base of the nut. A healthy vascular system is critical for nutrients (minerals and carbohydrates) to be transported from the tree to the developing seed (pecan). The fibers you see in this photo represent only 1/2 of the shuck's vascular system. A networks of vascular bundles also covers the outside of the husk. When visualizing the vascular system of the shuck as a whole, start at the base of the nut where it is attached to the tree. The flow of nutrients from the tree into the nut starts through the outer vascular bundles towards the tip of the nut. Once the nutrients arrive at the tip of the nut they travel through the inner vascular bundles to the base of the shell. All the water, minerals, and carbohydrates needed to build pecan kernel enter the nut through vascular connections at the base on the shell.  So it is easy to see that any pest that damages the husk of the nut will reduce kernel fill.

Recovery from the 2007 Ice Storm

    I can still recall the terrible sound of limbs breaking off of pecan trees during the 2007 December ice storm. Crack! It sounded like we were in a war zone. It took us almost 6 months to clean up and prune up our pecan grove. The first question on our minds was, "when would these trees recover from the limb breakage and when would the trees begin to bear nuts again?"
     We now have our answer. In the photo at left you can see the shadow of large limbs that had be snapped off during the ice storm. From those broken limbs, new sprouts have emerged, first shooting straight up, but with time, developing many short side branches. This year, the third growing season after the storm, we are seeing nut production on the side shoots of new wood grown since Dec 2007.

    Our recovery plan for getting back into nut production following the ice storm was simple. Keep doing what we always have done. That means we maintained our normal fertilizer program and continued to control insects and diseases as needed. Each year we apply 150lbs urea/acre plus 100 lbs potash/acre over the entire pecan grove around March 1. We add an additional 100 lbs urea/acre to the grove shortly after October 1. We have continued using early season fungicide sprays( in June) to maintain leaf health. We have also controlled all insect pests when they appeared. The key was to keep the trees in good condition so they could grow new, nut-bearing limbs that will replace those limbs lost in the ice storm.