Unusually mild temperatures are forecast to linger in the U.S. Plains and Midwest through this week, potentially advancing the growth of the region's winter wheat, weather and crop experts said on Friday.
An early growth spurt could leave the crop vulnerable to freeze damage later in the season, although forecasts currently show no such risk.
"We are looking at 10 days of substantially warmer-than-normal conditions across much of the country," said David Streit, an agricultural meteorologist with the Commodity Weather Group.
Winter wheat is planted in autumn and goes dormant during the winter before resuming growth in early spring.
Oklahoma's wheat is already developing about seven to 10 days ahead of last year, Oklahoma State University small grains specialist David Marburger said. Oklahoma is the second-biggest U.S. winter wheat producer.
"Since we started greening up earlier, having a freeze in that mid-March time frame could do more damage than it normally would," Marburger said.
The warm spell has cost some Oklahoma producers a few days of grazing on wheat pasture, Marburger said.
Cattle can graze on wheat during the winter months without affecting the crop's yield potential. But producers who plan to harvest the wheat for grain need to remove the animals once spring growth begins.
Temperatures in the Plains in the coming days were expected to reach the upper 60s and low 70s Fahrenheit (20-23 degrees Celsius) as far north as Nebraska, with parts of Texas and Oklahoma reaching the low 80s.
Farmers in the southern Plains grow hard red winter wheat, the most common U.S. variety, used to make bread.
In the Midwest, the warm weather will affect soft red winter wheat, used in cookies and crackers. Midwest temperatures should peak in the 60s this weekend.
Winter wheat plants start using more moisture once they resume growth. One risk for the soft red wheat is dry conditions across Missouri, southwestern Illinois and northern Arkansas, Streit said.
However, he said, cooler weather at the end of February should slow Midwest crop growth.