Wheat producers should monitor fields closely for freeze injury
Shroyer explained early signs producers might have noticed right away:
* Silage smell. If a wheat field is giving off the aroma of silage, it indicates that leaves have been damaged. Damaged leaves will likely turn black within a few days, then become bleached. If the flag leaf is killed, that tiller won’t produce much, if any, grain. Damage to lower leaves will not have such a drastic effect. Even if the flag leaf on the most advanced tillers is lost, less developed tillers can still come on and produce grain at this point in the season.
* Ice in the stems. If there was ice in the stems below the first node the morning of the freeze, those tillers will probably be damaged (although not always) and may not produce grain. When inspecting a field, flag the areas where you find ice in the stems, and tag individual tillers with suspected damage. Then come back to those areas after three days and see if the stems are crimped and damaged. If so, that tiller will probably not produce a head. If the tagged tillers continue to grow and put out nice green leaves, they are fine. If not, they probably had injury.
* Lodging. If the wheat lodged immediately after the freeze, that indicates stem damage. Later tillers may eventually cover the damaged tillers.
If the main tillers are injured, secondary tillers may begin growing normally and fill out the stand, Shroyer added.
“The wheat may look ragged because the main tillers are absent, but enough tillers may survive to produce good yields, if spring growing conditions are good. If both the main and secondary tillers are injured, the field may eventually have large areas that have a yellowish cast and reduced yield potential,” he said.
More information on freeze damage to wheat is available in “Spring Freeze Injury to Kansas Wheat,” K-State Research and Extension publication C646, available at county and district extension offices and on the Web at: http://www.ksre.ksu.edu/bookstore/ and type in C646 in the search function.