Ag Instructor Vic Martin: Summer Crops and Winter Wheat | Barton Community College

Ag Instructor Vic Martin: Summer Crops and Winter Wheat

Great Bend Tribune
Published April 8, 2018

The drought hasn’t lessened with the area in extreme drought and the outlook isn’t promising.  As if that wasn’t enough to worry about, the area has experienced well below freezing air temperatures (the low 20s) for an extended period of time twice in the last week which while not rare is certainly uncommon for the first week of April.  So what does this mean for the 2018 wheat crop?  As is almost always the case, there isn’t a cut and dry answer.

This is being written on Thursday and the weather forecast is predicting record or near record lows Friday night and up to two inches of snow in the area.  Has the wheat crop been damaged?  Here are items to consider:

  • Wheat is lagging in development.  Jointing, or hollow stem is late and where there is a hollow stem, the wheat is short.  Why does this matter?  Until jointing the growing point and developing head are protected below the ground.  After jointing the head is above ground and moving upwards and much more vulnerable to freeze damage.  Unjointed wheat should be safe as should unjointed tillers.  And if tillered, the developing head should have been close to the ground and that helps protect is some as heat radiates from the ground and temperatures should be warmer.  So here the cold weather slowing development was a good thing.  This is positive but may be lessened by the next point.
  • If the wheat is well-established and well-tillered, that serves as insulation to help protect the growing point.  However, thinner stands where it is still easy to see individual rows is more vulnerable to damage.  Snow prior to Saturday’s predicted record lows would greatly help.
  • What is the soil moisture status?  Drier soils warm and cool more rapidly and moist soils “hold” heat more effectively and are better able to protect the growing point.  To tie in with this, plants with adequate water contents are better able to withstand cold than drier plants.  Cold combined with dry leads to more vulnerable plants. 
  • While plants are no longer dormant and won’t become “winter hardy” again, if the temperature drop is somewhat gradual it will allow the plants some ability to cope.  However going from temperatures in the 70s to the teens in less than 48 hours isn’t helpful. 
  • How windy will it be if the wheat isn’t snow covered?  Wind speeds up heat removal and can desiccate leaf tissue.  Although with all the other challenges the crop is facing, this is relatively minor.
  • How long will the well-below freezing temperatures last?  All indications are for an extended period of time, long enough to potentially damage growing points.
  • What will the weather be like after this cold?  The worst scenario would be for rapidly warming, above normal temperatures.  The forecast as this is being written is for above normal temperatures this week.

It is likely some wheat will be damaged and with the forecasted weather this week, the damage should become evident soon.  If there is a silver lining it is that unless producers have limited crop choices with herbicide selection, there is time to abandon the wheat crop and switch to a summer row crop. 

 

barton wordmark