Easter freeze damage prunes wheat yields
Jun 29, 2007 9:38 AM,
By Elton Robinson
Farm Press Editorial Staff
The extent of damage to the Mid-South wheat crop from an Easter freeze and the cold temperatures that lingered for a week after are becoming apparent as harvest nears completion in the northern Delta.
Chris Main, cotton and small grains production specialist, University of Tennessee, has seen yields from zero to 65 bushels. “For us, it came down to three factors — when the wheat was planted, how well it was managed and where it was planted with respect to the landscape.”
If growers planted early, particularly before Tennessee’s recommended planting date of Oct. 15, “yields were pretty much a zero.”
Ironically, better-managed wheat did worse, according to Main. “Wheat fields with timely nitrogen applications and weed control were hurt worse because they had a head start.”
Fields in low spots where cool air collected during the freeze “would be lying on the ground, where the same variety, planted the same day and managed the same way, but up on a hillside across the road was perfectly fine.”
Wheat harvest was nearly complete in west Tennessee and many growers were waiting for a rain to plant soybeans. Main believes enthusiasm for wheat is still strong, especially with futures prices near record highs.
According to Jason Kelley, wheat and feed grains Extension agronomist, University of Arkansas, wheat yields in the state are highly variable. “In southeast Arkansas, there is very little if any damage (from the freeze). The farther north you go, toward Stuttgart and Dewitt, which are some our big wheat producing areas, yields are coming in anywhere from zero to 100 bushels.”
Kelley said two factors determine the level of yield loss — planting date and wheat maturity, essentially, any combination of planting date and maturity that resulted in rapid growth of wheat during an abnormally warm March.
“The wheat that was furthest along got hurt the worst,” Kelley said. “A lot of it was right at flowering or near flowering. And that is the most sensitive stage for wheat.”
Extreme yield variation often occurred in fields on opposite sides of a turn row, said Kelly. “According to one of our county agents, a variety trial planted all on the same day had yields ranging from 5 bushels to 70 bushels per acre. That’s dramatic.”
Ironically, the freeze would not have had such an adverse impact had there not been good growing weather during March. The ideal temperatures put the crop at least 10 days ahead of normal.
Many of the early-maturing varieties hurt by the freeze were popular among growers looking for high yield potential and the opportunity to harvest quickly and get soybeans planted to take advantage of high bean prices.
Despite the setbacks, with the price of wheat futures over $6, “growers are getting excited again,” Kelley said. I suspect there will be a considerable amount of wheat planted this fall.”
The freeze continues to impact management of the Arkansas corn crop, according to Kelley. “Prior to the freeze, the Arkansas corn crop was well ahead of schedule. Early March to mid-March, we put the corn in the ground and eight days later it was up. We had some big corn when that freeze hit. We replanted a considerable amount, probably a third of the crop.”
The result is “all different stages of growth out there,” Kelly said. “Extreme southeast Arkansas didn’t have a freeze, and corn there kept right on growing. Farmers will be through harvesting that at the end of July.
“Then we have replant corn, some of which was not replanted until late April and the first part of May. Producers are going to have to really stay on top of the water on replant corn. Most producers have done that, but some are in a bind trying to flood up rice fields or water something else, which has put a demand on resources.”
The replant corn this year may also be more susceptible “to southern rust later in the season,” noted Kelley. “A fungicide may help preserve stalk quality, which could be helpful if corn has to stay in the field a little longer prior to harvest. But I don’t think there would have been very much corn sprayed this year if it were not for fungicide programs that companies offered.”
Those programs remove or reduce the cost risk of using a fungicide. Essentially, if an increase in yield from the use of a fungicide doesn’t offset the cost of the fungicide, the programs offer to pay the difference.”
e-mail: erobinson@farmpress.com
