The Mississippi Commissioner of Agriculture and Commerce is advising Mississippi farmers to report freeze damage in their wheat and corn crops to their USDA county Farm Service Agency offices as soon as possible.

“FSA’s assessment is a necessary first step in determining if Mississippi farmers will qualify for federal disaster assistance,” said Lester Spell, who oversees the Department of Agriculture and Commerce from its offices in Jackson.

He said the freezing temperatures that occurred in the state April 8 and 9 appeared to have occurred at a crucial time during the crop production cycle for wheat and corn growers.

Farmers have 15 days to report damage from weather events, according to Farm Service Agency officials. For those whose crops were freeze damaged on April 8, the deadline would be Monday, April 23.

Extension specialists at Mississippi State University and other land grant institutions have been trying to prepare estimates of crop losses due to the freezing temperatures that occurred in portions of Mississippi April 8 and 9. But they say determining the damage and which fields can be recovered and which should be replanted is a slow process.

“As time passes, freeze damage to our wheat crop is becoming more apparent,” said Erick Larson, Extension corn and wheat specialist at Mississippi State, who has been visiting farms all over the state.

Larson said field evaluations have confirmed that wheat freeze damage was closely related to crop growth stage and low temperatures.

“Wheat is most sensitive to freezing temperatures while flowering, a few days after head emergence. Severe injury has been documented where temperatures fell to 30 degrees F or less on heading wheat or 28 degrees F or less on wheat in the boot stage.”

Assessing freeze damage in wheat can be tedious, he said. Damage is likely to differ from stem to stem, since maturity naturally varies by a week or more in most fields. Damage may also vary depending upon floret location.

“Damage can be partly assessed by the presence of yellow, discolored heads, which are gradually turning white or light brown as the tissue dries,” says Larson. “Wheat-freeze damage must also be assessed by observing grain development of successfully pollinated kernels.

“Pollination normally occurs within three to five days of head emergence. After pollination is completed. Wheat kernels rapid develop and attain their full length with about 12 days after pollination.”

Larson says free-damaged kernels may be shriveled or halt development all together. “These kernels will not likely develop appreciable seed weight. Close monitoring of freeze-damaged fields should reveal kernel development problems within a few days, since kernel development proceeds rather quickly following pollination.”

While cold, cloudy weather delayed corn recovery until recent days, several consecutive days of bright sunshine and warmer temperatures have revived many fields, which appeared dead last week, Larson noted.

“Corn can recuperate from complete freeze defoliation because the vital growing point of young corn plants was generally protected under the soil surface,” he said. “Shallow planting or poor seed furrow-slice closure are likely culprits for growing point exposure to freezing temperatures.

“Fortunately, dry soils during March encouraged deep planting, which enhanced growing point protection from direct freeze injury.”