Another heat wave is building during a critical time for corn crops
AMES — The forecast calls for hot — and still hotter — weather for Iowa this week and it’s doing no favors for Iowa’s top crops.
Meteorologist Dennis Todey, director of the USDA’s Midwest Climate Hub in Ames, says the average rainfall for late July doesn’t bode well for the soil, which is already suffering under moderate to severe drought over a wide section of the region.
“That’s the climatological average but weekly EP, or evapotranspiration, how much water the crop is using out of the soil, is probably going to be more than that,” Todey says. “So, even the average precipitation this time of year, you’re losing ground into that soil moisture.”
Recent rains were exceptionally heavy in some areas of Iowa, prompting flash flooding. Still, Todey says the soil moisture has been depleted for months across much of the state’s northern half and highs of 95 degrees won’t help.
“The soil moisture is rather short in that area,” he says. “Even low 90s will be causing some problems. That’s why this recent precipitation has been helpful in some of the areas further south where they could stand a little bit more temperature at this point. We’re entering that time when we could kill a crop or manage get through it.”
Corn is reaching a critical pollination stage while soybeans will be more at-risk during August.