One branch sums up the 2014 growing season

     Recently, I cut a single limb from an Osage tree that seemed to sum up the entire 2014 pecan growing season (photo above). First, let me tell you what all those letters in the photo mean.
  
     VS= vegetative shoot
        F= buds frozen by a late spring frost on April 15, 2014
        P= pedicle from the 2013 nut crop
     FS= fruiting shoot

    We harvested a good crop of nuts during the fall of 2013. Judging from the fruiting scars on the pedicle (the portion of the stem that supports a cluster of nuts) this shoot bore three nuts in 2013. When spring rolled around buds started to swell but were frozen by a late spring freeze. The remnants of two buds frozen buds are still firmly attached to the stem. After the freeze, two dormant buds lower on the one-year-old branch broke and started to grow.        
    As these two new shoots grew out in the spring, only one of the shoots produced a pistillate flower cluster. The bud that broke from the lowest portion of the one-year-old stem remained vegetative. This is fairly typical for pecan. The oldest buds (lowest on the stem) on last year's wood have the least potential to produce female flowers.
    When we harvested the 2014 crop, we collected about half as many nuts as we harvested in 2013. Judging from what we can see on this single branch the reasons for lower yields in 2014 become clear.
   

Mohawk: A precautionary tale

   We only have one Mohawk tree left growing at the Pecan Experiment Field (photo at right). Thirty 35 years ago, Mohawk was among the most popular cultivars being grafted in our region and we had dozens of Mohawk trees growing on the farm. At first look, Mohawk had everything a pecan grower would want--large nut size, thin shell, early ripening, and young trees that were both very precocious and productive. The story of Mohawk and the reasons this cultivar has been removed from pecan orchards all across the US is a tale that I always keep in mind as I evaluate new pecan cultivars.     

Mohawk pecans, 2014

    The story begins in 1946 when USDA pecan breeder, Louis Romberg, applied Mahan pollen to a Success pistillate flower. The resulting seed was germinated and grew into a tree that was later named Mohawk in 1965.
     At one time, the Success cultivar was the most popular cultivar grown in the Southeastern US. Success originated as a seedling tree planted in 1875 on a farm near Ocean Springs, MS.  This cultivar produces large thin-shelled nuts but as  the tree matures, nut production becomes erratic and kernel quality suffers terribly during "on" years. As plantings of Success increased across the Southeast, this cultivar became susceptible to pecan scab by 1931.
   Mahan is another cultivar that can trace its origins back to a Mississippi seedling pecan orchard. The tree originated from a seed planted in 1910 near Kosclusko, MS and was named after the nurseryman that first propagated the cultivar. Mahan is known for its very large nut size and long pointed nut shape. However, Mahan is now better known as a cultivar that never fully fills the inside of that large shell with kernel. Mahan is severely alternate bearing and often suffers cold damage following a heavy crop year.

     When Louis Romberg decided to cross Success with Mahan, he was hoping to produce a new pecan cultivar that would exhibit the best qualities of both parents--large nut size, precocious flowering, and heavy nut production. In the photo at right, a single Kanza nut is flanked by two Mohawk nuts. Mohawk is indeed one of the largest pecan cultivars that will ripen before frost in our area. As a young tree, Mohawk produces big beautiful nuts that are well filled and impressive to the consumer. But like both of its parents, serious problems arise when the tree reaches maturity (around 20 years old).    

    Mature Mohawk trees are similar to Success trees in that they frequently set too many nuts on the tree. This leads to poor kernel filling and the development of alternate bearing.  The photo at right illustrates the poor kernel filling of Mohawk as compared to a plump well-filled Kanza nut. Note how much space there is between the shell and kernel of the Mohawk. In addition, the kernel is fuzzy and the tips of the nut meat are shriveled. 
     Mohawk is also similar to Mahan in terms of susceptibility to cold injury. The vast majority of Mohawk trees that once grew on the research station were removed after winter cold killed trees to the ground. This type of extreme cold injury always occurred following a heavy crop year.
     As we grow and evaluate new cultivars, I always keep the story of Mohawk in the back of my mind. What may look like an outstanding new cultivar when a tree is young may turn out to be a real dud when the tree reaches maturity. The history of pecan cultivar development is littered with examples of pecans that fall apart at tree maturity. I'll name a few just off the top of my head: Shoshoni, Chickasaw, Creek, Dooley, Giles, Maramec, and Mohawk. 

Another great day for harvest

    Today was another absolutely beautiful day for harvesting pecans. We broke out the old Lockwood pecan picker to harvest one of our cultivar trails (photo at right). This Lockwood machine may be over 40 years old but it still the best machine for harvesting the small, two-tree plots in this trial. Each cultivar is painted with a different color code to make identifying plots easy from the seat of the shaking tractor or harvester. Trees with yellow paint are Greenriver. Red and green paint on the same tree indicates a Chetopa while blue and white means Giles. There are 9 cultivars in this trial with each cultivar having a different color code. It definitely makes for a colorful orchard.

       When the Lockwood picker was designed back in the late 1960's, pecans were handled in burlap bags. Once the hopper gets full of nuts, we pause the machine, drop the out-feed gate, and the nuts come pouring out (photo at left). This system was originally designed to pour nuts into a burlap bag but we have refitted our Lockwood with a longer out-feed chute capable of  dropping the nuts into an portable elevator.

    The elevator lifts the nuts up and drops them into a waiting super sack (photo at right). This way, we can use a tractor for all the heavy lifting instead of getting a sore backs.
   We mounted the elevator on an axle and wheels to allow us to move it around the pecan grove.  A gas-powered,  electric generator provides the electricity needed to power the elevator.

The rush to harvest pecans is on!

   On this day after Thanksgiving, many Americans spent the day rushing about in huge crowds of people at the local shopping mall. But on this warm and sunny day, we spent the day rushing around the pecan grove harvesting nuts. In fact,  the entire river bottom was humming with the sounds of pecan harvest as growers throughout the area worked to harvest the 2014 crop.

   At the Pecan Experiment Field, we use a stick rake (photo above) to remove fallen limbs knocked to the ground by the tree shaker. Once the sticks are raked off the orchard floor, we use a pull-type harvester to sweep pecans up off the ground (photo at left).
   After putting in a long day of harvest today, I gained two impressions of this year's native pecan crop. Yields are below average and we are shaking out a lot of dead wood. These outcomes  are probably related to the several years of drought we've experienced recently and the late spring freeze of 2014.