After record-breaking spring rainfall, it is difficult to believe any living thing in the Four State area could need more water. For late or early planted summer crops, however, summer is a critical time to look for signs of stress.
During an interview for Oklahoma State University’s SUNUP TV, cropping systems specialist Josh Lofton said while soil moisture might be adequate, farmers should keep a sharp eye on their crops’ progress.
“All of the rain we got a few months ago almost lulls you into a false sense of security,” Lofton said. “If you actually dig down in a lot of these fields, we actually have a substantial amount of subsoil moisture.”
Soil moisture isn’t at the root of drought symptoms in plants like corn and sorghum, Lofton said. Root structure in those crops may not be developed enough for plants to obtain moisture from deeper in the soil.
“Even if you have a lot of moisture down low, your crop could be getting a little dry and drought stressed because it just doesn’t have the root structure yet,” Lofton said. “The more stressed it gets, the further the roots will stretch.”
Lofton said crops planted early in the season or exceptionally late in the season would be the highest risk for drought symptoms. He encouraged producers with late-planted corn to check their kernels for mis-polination, or skips in between the kernels in their cobs due to pollination happening during periods of higher temperatures.
Scouting is a critical mission in the summer months both for corn and sorghum. Lofton said sorghum growers will see leaves curl during high temperatures and not to be alarmed, especially if the curling appears in the hottest part of the day.
“That's OK; that's part of what that crop does. It's trying to mitigate itself from those 100-degree days by decreasing that surface area and kind of rolling itself up,” Lofton said. “As long as we're not rolled up at 8 or 9 o'clock in the morning, or deeper in the evening, we're OK.”
Timing scouting is important to gain an accurate picture of the field’s status, Lofton said.
“At 3 or 4 o'clock in the afternoon, it's probably not a good time on a 100-degree day to check and see if you're in drought stress,” Lofton said. “Go out there at 8 or 9 o'clock in the morning when we have cooler temperatures, the humidity's up, and then see if that crop is still rolled up.”
Lofton said scouting all crops is important this time of the year — for soybeans as well as corn and sorghum.
“So right as soon as those soybeans are flowering and starting to set pods — that's where we can lose a lot of yield really early,” Lofton said. “If we let those foliar-feeding insects and those pod-feeding insects get at those really small pods as they're developing, we lose yield, so growers need to get out there, get their sweep nets out and get their checking boots on because it's time to get out in your summer crops.”
University of Missouri field specialist, Pat Miller, scouted fields near Nevada Missouri and reported a light infestation of garden webworms. She advised producers to be on the lookout caterpillars and webbing in the area.