A costly deadline looms for many growers in the Midwest, as every day of waiting for the weather to cooperate to plant corn and soybeans reduces potential yields. Research indicates that Illinois growers who plant corn or soybeans near the end of June can expect a 50% reduction in crop yield, according to a University of Illinois agriculture expert.

The USDA reports that corn and soybean growers in several Midwestern states are behind schedule on their planting. A cooler and wetter-than-average spring has left Illinois and Indiana furthest behind on planted corn and soybeans. Several other states are lagging behind their normal planting schedules, but by a lesser margin.

In Illinois, 95% of the corn is planted and 88% has emerged, but less than half of that is reported to be in good or excellent condition. Fully 14% of the acres planted are in poor or very poor condition, with another 38% reported as fair. Those acres in poor or very poor condition may have to be replanted.

In Illinois, the corn was 7 in. high as of June 9, compared to an average of 17 in. by this time in recent years.
Illinois crop sciences professor Emerson Nafziger says cool temperatures and the third wettest January-April since 1895 in Illinois have led to delays that are undercutting potential yields.

"This has been a bad spring by most measures," Nafziger said." We keep seeing forecasts that look favorable and then that doesn't happen. The chance of having above-average yields has diminished greatly."

Cool temperatures and the third wettest January-April since 1895 in Illinois have led to delays that are undercutting potential yields. Nafziger's analysis of previous years' corn planting data in Illinois determined that "we can expect 50 percent of the maximum yield when planting is done around June 15-20."

Those growing soybeans in southern Illinois may get 50% of their maximum yield if they plant no later than June 25-30, he said.
Some growers -- in southern Illinois especially -- will have to replant as wet conditions have caused some seed to rot.

Despite the poor conditions, Nafziger finds it encouraging that 95% of Illinois corn acres have been planted. While some acres will have to be replanted, high temperatures should help boost the growth rate of what has survived, he said.

Soybeans are further behind as only 66% of the soybean crop was in the ground as of June 9 in Illinois, compared to an average 92% planted by this time in recent years.

Most growers will not get the yields they expected, but high prices for their crops -- and crop insurance -- should see them through, Nafziger said.

U of I Extension offers Web advice on crop insurance and crop planting issues, including resources describing final planting dates, prevent-planting provisions relative to crop insurance, options when corn stands are marginal, and options when no crop has been planted.

"Even with high costs, the yield needed to cover costs is relatively low when corn is more than $6/bu.," he said. "But we're looking at some real disappointment at having so much income potential not realized this year due to weather-related crop problems."