Don’t Panic! But there may be Freeze Damage to Kentucky’s Small Grains

Carrie Knott, Extension Agronomist-Princeton, University of Kentucky (Twitter: @KyGrains)

Conner Raymond, Extension Assoc.-Princeton, University of Kentucky

Once again, freeze damage in wheat is a topic of conversation/concern.

Temperatures during the overnight hours of March 31, April 1 and April 2 dipped below freezing across much of the state. In some areas, lows were in the low 20s.  See also - http://news.ca.uky.edu/article/time-kentucky-wheat-growers-check-freeze-damage.

Low temperatures (°F) from the morning of April 2. Data from https://www.kymesonet.org/. Compiled by Matt Dixon, UK Ag Weather Center.

Although low temperatures were quite cold, temperatures across the wheat producing areas did not remain at levels that would be expected to result in freeze damage. The most advanced wheat across Kentucky was about Feekes 6 to 7. Therefore, temperatures of 24°F or less for two or more hours would be expected to result in damage.

Data complied by Matt Dixon, UK Ag Weather Center.

However, there are beginning to be some isolated reports that freeze damage has occurred. For example, all small grains at the UK Research and Education Center have sustained some level of damage. 

Developing wheat head at Feekes 7 growth stage with damaged spikelets (structure that hold the developing seed) that are bleached white and break easily when touched. Healthy heads should be bright green in color, shiny and not break easily.

Damaged developing wheat head (brown ‘line’ in the middle of the stem) at Feekes 6 growth stage.

Healthy developing wheat head at Feekes 6 growth stage. It is translucent, shiny and firm to touch. The length of the head (between the two arrows) is about 1/8”.