Current Crop Situation
I’ve gotten lots of calls and questions over the last day or two about what impact the cold snap this weekend will have on the wheat crop. With the mild winter so far, many wheat fields in South Arkansas have more growth than normal. In particular, fields that were planted early following corn (with residual nitrogen) and planted with early maturing varieties seem to be the most developed. There are some of these fields that unfortunately have already started to joint (see photo below). Fields in central and northeast Arkansas are much less developed and growth stages are closer to what we would expect in a normal year and have not yet begun to joint.
Low temperatures at this point are forecasted to be 18-22 degrees F for many South Arkansas wheat producing areas on Sunday morning with slightly milder temperatures forecasted for Saturday morning. Temperatures for Northeast Arkansas are expected to be 13 to 18 degrees F Sunday morning. Temperatures this low can and most likely will cause some freeze damage on fields that have already started to joint – when wheat is much more sensitive to freeze damage. Kansas State University has an excellent reference article on spring freeze damage in wheat at: http://www.ksre.ksu.edu/library/crpsl2/c646.pdf
The fields with concern about freeze damage are those that are jointing. Temperatures down to 24 degrees F are cold enough to cause damage.
Fields not jointing yet, but have greened up and started active growth in the last week or so will likely suffer leaf burn, but can tolerate considerably colder temperatures without significant injury.
After the freeze, any damage will take a few days or even weeks to fully see the impacts. Injury that may be seen includes burned/dead leaves, stem damage, and death of the developing head. Time will tell, but hopefully temperatures will be warmer than forecasted.