Most corn handling Wisconsin’s heat wave
A University of Wisconsin expert says the recent hot temperatures have not caused major problems for the corn crop in his state.
Joe Lauer tells Brownfield much of Wisconsin received up to four inches of rain over a week ago, but the heat will slow down grain fill. “The crop begins to shut down at about 94 degrees, 90 to 94 degrees Fahrenheit, and that’s where photosynthesis cannot keep up with the respiration of the plant.”
Lauer says if the yield is expected to be 200 bushels per acre, the plants are adding an average of five to six bushels per day, but that slows down when it’s very hot. “Although we’ve had these higher temperatures, we might not have gotten five to six bushels but, there’s certainly some yield that was developed and as these cooler tempuratures come on, the plant will again restart filling those kernels again.”
Lauer says most of the corn is still green throughout the stalk in Wisconsin, but for farmers concerned about early senescence and dry lower stalks, remember it’s the ear leaf that provides 60% of the grain fill, and if the leaves closest to the ear are green, it’s still gaining yield.