COLUMBUS, Ohio -- For Ohio growers looking to replant field crops due to weather-related damage or emergence problems, they are better off replanting with soybeans rather than corn at this stage of the growing season.
Peter Thomison, an Ohio State University Extension corn agronomist, said that corn is not recommended as a late crop after mid-June due to substantial yield loss.
"We can lose as much as 50 percent or more of our yield potential when corn is planted in the latter half of June. We lose about 1 to 2 bushels per acre with every day of delayed planting after the first week of May, with the yield loss increasing the later it gets," said Thomison, who also holds an appointment with the Ohio Agricultural Research and Development Center. "The exception to late-planted corn is if the crop is being grown for silage and nitrogen and corn herbicides have already been applied."
Soybeans, on the other hand, can be planted as late as early July and can yield up to 65 percent to 75 percent of normal after mid-June.
"A key consideration in late soybean plantings is planting the latest maturing variety that will reach physiological maturity before the first killing frost," said Jim Beuerlein, an OSU Extension soybean agronomist.
Weather conditions, especially adequate soil moisture, often limit the yield potential of both late-planted corn and soybeans, but corn is a much riskier crop.
"Corn is highly susceptible to drought damage during pollination and early grain fill and the potential for high temperature and water stress typically increases later in the growing season when late-planted corn flowers," said Thomison. "Because soybeans flower over a longer period, they are usually less vulnerable to this type of injury."
Thomison said there are several other factors to consider with late-planted corn including:
• Higher grain moisture that may require artificial drying.
• Lower test weights that may result in significant dockage.
• Greater stalk lodging and stalk rots that may slow harvest and reduce yield.
• Increased injury from silk clipping insects like corn rootworm beetles and Japanese beetles.
• Greater injury from foliar diseases. Losses to gray leaf spot may increase with later planting dates.
• Less effective nitrogen uptake. If conditions turn dry after planting, late sidedress nitrogen applications may be ineffective.
After delays due to a wet spring, Ohio corn and soybeans are finally in the ground. Though some growers are facing a replant situation, the issue is relatively minor compared to previous years.
"It's not the tremendous acreage like we had last year," said Beuerlein, who also holds an Ohio Agricultural Research and Development Center appointment. "There have been only minor replants this year, at least for soybeans."
Beuerlein said that despite the week to 10-day planting delay, soybeans are fairing well for their stage of growth.
"The early planted beans are pretty much at the same point of growth as the late-planted beans, because we've had cool, dry conditions that haven't been conducive to development. When soybeans first come up they don't grow very fast anyways because they are developing their root systems and nodules for nitrogen fixation," said Beuerlein. "But we have good stands. Now we just need warm weather and plenty of rain."
According to the Ohio Agricultural Statistics Service, corn is doing just as well as soybeans, with 97 percent of the crop in fair to excellent condition. Ohio, overall, has emerged from planting in much better condition than other states to the west. States such as Illinois, Missouri and Indiana were still struggling to get their corn and soybeans in the ground by the second week of June.
For more updates on Ohio's field crops as the season progresses, refer to the OSU Extension Agronomic Crops Team Web site at http://agcrops.osu.edu.