Pecan Mid-Winter twig health check

     The 2018 pecan crop was much smaller than we all expected and the harvest season came and went in record time. When winter arrived, the cold and blustery weather has keep me out of the pecan grove for the most of December and January.  On the morning of January 30, a polar vortex passed through SE Kansas and dropped our temperatures down to 8 degrees F (-13 C). If you believe the news media, this cold was record breaking (it was not, in December 1989 I recorded -26 F or -32 C). However, whenever it gets really cold outside, many pecan growers start to worry about the cold hardiness of their trees. Over this past weekend (Feb. 2-3), temperatures moderated and I was able to go out to my trees and check on the health of pecan twigs following the recent cold snap.

    In mid winter, dormant pecan twigs are at their most cold hardy state. To check for damage to twigs, I used my knife to peel back the bark and expose both phloem and cambial tissues. Healthy tissue should have a bright green appearance such as the twigs of Faith, Greenriver and Kanza in the photo above. Other perfectly healthy cultivars (checked but not pictured) included Hark, Jayhawk, Oswego, and Yates 68. Only Lakota showed signs of minor twig damage from cold. In the photo above note that under the bark of the Lakota twig the tissues appear dull green. This level of cold injury should have no effect on Lakota's ability to break bud and flower come this Spring. Serious cold injury is indicated by extensive browning of the tissues under the bark which becomes more prevalent when mid-winter temperatures drop to less than -10 F (-23 C). As of now, our pecan trees look just fine.