Pecan bud break and flowering type

    It seems like spring has come in a hurry and our trees are developing new shoots at a rapid rate. This morning, I photographed emerging buds of several pecan cultivars. I found some cultivars had buds that were just starting to expand while others were already expanding their leaves. I used this variation in bud break timing to create a series of photos that illustrates how protandrous flowering pecan trees (early pollen shed) break bud differently than protogynous flowering cultivars (late pollen shed).

 
    Today, Surecrop and City Park pecan cultivars were just starting to expand their buds (photo above). At this point in bud development, you really can't see any difference in bud break appearance between the protandrous and protogynous cultivars.

    The buds on Major and Kanza trees had vegetative buds that had expanded to the point you can see leaves about ready to unfurl (photo above). At this point in bud development, the difference between the protandrous Major and protogynous Kanza is readily apparent. Major has pushed out catkins while the catkins on Kanza are still not visible.

     Faith and Lakota trees had leaves that were well developed (photo above). At this point, the protandrous Faith cultivar had well developed catkins while the catkins on the protogynous Lakota cultivar were just starting to emerge from their bud scale coverings.
     As your trees break bud this spring, you might want to check out this phenomenon on your pecan trees.

Warm night temperatures advance pecan budbreak

     Last night, overnight low temperatures did not drop below 60 F. Suddenly all the trees in the area look like they are bursting with new spring growth. Pecan trees are no different. Today I found catkins emerging on a tree that has a protantrous flowering habit (photo at right).

    The buds on protogynous flowering trees have also advanced with new leaves poised to unfurl (photo at left). Catkins on these trees are not visable at this time but will soon break out of the two narrow, tapered buds that appear on either side of each central vegetative bud.
   

    Emerging shellbark hickory buds are massive (photo at right). If you look carefully you can spot two catkins poking out from under a bud scale mid-way along the expanded bud.
   The emergence of new growth in the Spring always gets me excited for the coming season. We'll be grafting soon, followed by a long summer of watching this year's nut crop grow and mature.  

Pecan trees breaking bud

    All week, I've been watching pecan trees as the buds start to swell and the first signs of new green growth appear. What I've noticed is that not all pecan trees break bud at the same time. I'm not talking about the timing of pecan budbreak in Texas vs. trees growing in Kansas. The differences I've noticed this week have been among trees all growing in my local area.    

    Earlier this week, I noticed that the Kanza trees growing on my farm had buds that had split open to reveal just the first glimpse of green tissue. With my interest peaked, I immediately went down to the Pecan Field to check on the progress of Kanza trees at that location. What I found were Kanza trees with buds showing just the initial signs of bud development (photo at right).                    Here was the perfect example of how soil type can impact on early spring tree growth. The tree on my farm is growing in a Cherokee silt loam soil. The tree at the Pecan Field is growing in a Osage silty clay. The lighter the soil texture, the faster a soil warms up in the spring. Spring root growth is stimulated by warm soil temperatures and once the roots start to grow, bud growth follows shortly there after.

    In walking around the Pecan Field today, I spotted the obvious differences in bud development among pecan cultivars (photo above). Greenriver seems to be among the earliest trees to break bud while Chetopa was just barely splitting the outer scale.  By the time we get to pollination and nut set, the differences in budbreak date I observed today, will be totally indistinguishable.  However, all you need to remember is that last year we had a late spring frost that injured early leafing trees far more than the late leafing trees.     

Spring fertilizer application

    Spring has arrived a little later than normal this year. I've been checking pecan buds for several weeks now and have only recently seen signs of spring bud growth (photo at right). When the outer scales of primary buds split I know its time to spread some fertilizer. With light rain showers in the forecast, today was a great day to make our regular spring time fertilizer application.
    We have been following the same fertilizer program for over fifteen years and have had good results--higher yields and more consistent nut production. Remember, we make two fertilizer applications per year on our bearing pecan trees--Early spring and mid October. Today, we applied 69 lbs. N/acre and 60 lbs. K/acre. This fall, we'll spread another 46 lbs. N/acre.

   For today's fertilizer application, we used urea as our nitrogen source and potassium chloride (Potash) as our potassium source. We had our local fertilizer dealer mix 3 parts urea and 2 parts potash (by weight) and then used a rented fertilizer buggy to spread 250 lbs. of the mixture per acre (photo at left).