Monday, May 12, 2014

Flowering after a late Spring frost

   On the morning of April 15th, temperatures dropped to the mid 20's (F) freezing back all emerging pecan buds. The photo at right shows the impact the freeze had on Greenriver shoots by late afternoon that same day. The dark olive green color of the new growth indicates total freeze kill.  At the time of the freeze, Greenriver was one of the earliest budding pecan cultivars in our cultivar collection.
   A couple of weeks later, I went back to our Greenriver trees and found some signs of new growth amongst all the frost killed buds (photo at left). The question at that time was-- "Will our Greenriver trees have enough energy to produce pistillate flowers?".  I wasn't too worried about the production of catkins on frost damaged trees because I could already see catkins being produced adjacent to the new green shoots (visible in photo).
   Today, I took a ride in our hydraulic lift to check for Greenriver pistillate flower production.  The photo below is a common example of what I found. The tips of last year's growth were largely barren except for the remains of frost damaged buds. Buds at the base of last-year's-wood produced both new catkins (red arrow) and a strong vegetative shoots. On the end of many of these vegetative shoots I found pistillate flowers (inside red circle). So it looks like we are still going to have a decent pecan crop despite the April 15th freeze.
    I am convinced that our regular, twice-per-year, fertilizer program is largely responsible for our trees having the energy to produce pistillate flowers on shoots developing from basal buds.