March 21, 2023 - Low Temperatures

(Updated: March 24, 2023, 11:58 a.m.)

Potential Freeze Damage in Wheat

Depending on your location, the early morning hours of March 21, 2023 led to temperatures as low as 23 Fahrenheit and at or below 24 Fahrenheit for approximately 3 hours. Any wheat line that had already jointed was potentially susceptible to freeze injury due to loss of cold tolerance and inability to withstand an extended period of time below freezing without injury. The extent of the potential damage will appear a week after the freeze event. Early maturing varieities such as USG 3118, SH 7200, AGS 2024, Progeny #Berkeley, AgriMaxx 492 & 502, and Dyna-Gro 9070 were at most risk.

Below is a chart from a Kansas State publication showing wheat resistance to freeze injury at different growth stages. Also find more information from the North Carolina Small Grain Production Guide on freeze injury.

wheat resistance to freeze injury

When scouting, look at the first two nodes for damage on the the main stem. You can also split the stem to look for internal damage to the wheat head. Tillers that have suffered stem damage will have more difficulty translocating water later in the season and as a result will shut down faster during hot temperatures.

wheat production guide

If any tillers were lost, secondary tillers will compensate some but will only result in about 1/3 of the yield of a tiller formed in the fall. Seed size and test weight will also be decreased for secondary tillers in comparison. Below are some photos of wheat from sub 25 Fahrenheit temperatures on March 13, 2022 in Perquimans County.

damaged head

Damaged head

damaged vs healthy

Damaged vs healthy head above

damaged head

Damaged head

not damaged

Head that was not damaged - normally green or white vs brown when damaged

stem damage

Stem damage

tip burn

Tip burn from freeze

If you have any questions or need assistance with evaluating potential freeze damage, contact Dylan Lilley at 252-358-7822.