Scab resistant cultivars shine in 2015

Kanza trees just before shaking, 2015

   During the rush of harvest, I've made two important observations about the impact of pecan scab on nut production.
   1. This past summer, I made the decision to concentrate the dollars we spent on fungicides to protect improved but scab-susceptible pecan cultivars such as Pawnee, Giles, and Chetopa. We made three fungicide applications on these trees and achieved good but not perfect results. This fall we were able to harvest good crops of quality pecans from most improved cultivars (Hirschi and Dooley were exceptions). In contrast, I decided save money by making only a single fungicide application to our native pecan trees in the hope we could suppress scab enough to ensure a decent native crop. Unfortunately, my gamble didn't pay off. We are harvesting far fewer native nuts that I originally expected. When I shake our native trees, I'm seeing far too many black, scabby stick-tights hit the ground. It seems that 2015 was not a good year to experiment in cutting back on fungicide costs.
   2. Once all the leaves fell from the trees this fall, I noticed that trees with genetic resistance to pecan scab tended to be the heaviest nut producers in 2015. The scab-resistant Kanza, Lakota, and Major trees all produced heavy crops of high quality nuts. Although our fungicide program provided fair scab control on scab susceptible cultivars like Pawnee, Giles, and Chetopa, yield for these cultivars were good but not great.
    The 2015 growing season has made many new believers in the need to propagate scab-free pecan cultivars in their orchards. I know I'm grafting only scab resistant cultivar on my home farm next spring.

Revisiting a top-worked pecan tree

   We might be busy harvesting pecans this week but, I couldn't resist taking a photo of a tree that I top-worked back in 2012 (photo at right). Frankly, I was amazed at how well the tree had grown and was glad to see that all my pruning efforts yielded a nice central-leader tree.
    You can see how I grafted this tree and then trained the scion into a central leader by going back and reviewing previous blog posts I made about this tree. Click on the blog post titles to link back to those posts.

1. Top-working with a bark graft
2. Bark graft bursting
3. Training a new bark graft 
4. Summer training a bark graft
5. Summer pruning last year's bark graft
6. Directive pruning results

    Since I first grafted this tree, the scion has had four summers of new growth. The photos at left give you an idea how well this graft has grown. The cut surface on the stock tree has completely healed over and I now have a nice solid graft union.  In the 2015 photo, I've placed a red arrow to mark the spot where scion and stock meet. Notice the abrupt change in bark texture between the stock tree below and the scion above the red arrow.

     And finally I wanted to remind you why I needed to top work a fairly large tree in the first place. The 2012 photo at right shows the original tree before I started the top-working process. This tree had been severely damaged by an ice storm in 2007 and had grown into a tangled mess. Since the tree was originally grafted to the wrong cultivar for that location, I decided to change the tree over to the right cultivar and work on proper tree training all at the same time. By the end of the 2015 growing season, it looks like I've got a well shaped tree well on the way to nut production.

Starting pecan harvest

    We were able to start pecan harvest this week (photo above). The first trees that we were able to shake were some young Faith and Gardner trees in our "double-row" tree planting. Because we were harvesting experimental plots, we used our old Lockwood pecan harvester along with our small trunk shaker. Besides Faith and Gardner we were also able to harvest some Osage, Witte and Pawnee trees. Unfortunately, yesterday's rain showers has put a stop to our harvest for the time being.
    In cleaning the nuts we harvested this week, I noticed that the pecans were not fully dry. During the cleaning process, green shucks were knocked off nuts but that still left us with a sack full of nut that needed additional drying time. We placed cleaned pecans in burlap bags which will allow the nuts to dry down while being stored in the barn. 

A Kanza story

    Back in 1969, Dr. G. D. Madden, the USDA's pecan breeder at the time, sent a package of scions from several pecan selections to the Pecan Experiment Field for testing under northern growing conditions. Among those scions was a clone labeled USDA 55-11-11.  Back in those days, the staff at the Pecan Field grafted all new cultivars received for trial onto small native pecan trees that grew within areas of larger native trees. As it turns out, only one USDA 55-11-11 tree was successfully produced from that spring's grafting efforts and has now grown into a large tree (photo at right).
     When I first arrived at the Pecan Experiment Field in 1981, our 55-11-11 tree was already bearing regular crops of nuts. During the early 1980's, KNGA member, pecan enthusiast, and parish priest, Tony Blaufus made an annual trip to the Pecan Field to look over our cultivar collections. Tony had started a small grove of trees on his family's farm near Westphalia, KS and was interested propagating the best available pecan cultivars he could find. It was Tony that first pointed out  to me how well nuts from the 55-11-11 tree shelled out and how wonderful the straw-colored kernels tasted. That's when I decided to remove a couple of nearby native trees to give our lone 55-11-11 some more room to grow. I also started to graft additional USDA 55-11-11 trees into formal cultivar trials.

      In the early 1990's, I started to encourage the USDA to name and release USDA 55-11-11 as a new pecan cultivar for northern pecan producers.  I even suggested a name--Kanza.
    In 1996, Kanza was released and has since become one of the most popular nuts being propagated in northern pecan states. And what has happened to that single tree grafted back in 1969?  It is still standing and has grown to 25.1 inches in diameter (Photo at left).
    I have been fortunate to be able to watch a single Kanza tree grow from a young productive nut producer into a fully mature tree that reliably yields outstanding-quality pecans year after year after year. In the past, we've made cultivar choices based on the performance of young trees only to be disappointed by those same cultivars as trees mature. Too many times, I've seen cultivars that produced outstanding nuts on productive young trees only to mature into old trees with severe alternate bearing, poor quality kernels and susceptibility to winter cold damage. With Kanza, I've been able to watch this cultivar long enough (35 years) to know I won't be faced with future disappointments. 

     Kanza originated from a hand pollinated cross between Major and Shoshoni made by Louis Romberg in 1955. Louis was the USDA's first pecan breeder hired way back in 1931. The objective in making a cross between a northern cultivar (Major) and a large, thin-shelled cultivar of southern origins (Shoshoni) was to develop a new pecan cultivar with large nut size, thin shell and early ripening. The photo at right shows a Kanza nut and its shuck. When I look at Kanza, I can see characteristics from both parents. Kanza inherited the tear-drop shape, thin shell and excellent shelling ability from its Shoshoni parent. From its Major parent, Kanza inherited scab resistance, a thick firm husk, early ripening, and great kernel flavor.
     In the 1960's, many pecan "experts" judged USDA 55-11-11 not worthy of propagation. The nut produced was deemed too small for modern commercial orchards that only had room for cultivars that produced mammoth sized nuts.  At that time in our history, it didn't seem to matter if those big pecan produced kernels that tasted like cardboard. But times change, and consumers are becoming more concerned with kernel quality and flavor rather than just a big shell.  

    Kanza is among the best shelling pecans that can be grown. After cracking, Kanza nuts produce over 95% intact kernel halves (if the cracker is set properly). The kernels are golden in color and very attractive (photo at left). Get a customer to taste a Kanza kernel and you'll have them asking for the nut by name from now on.