By KAREN BINDER
Illinois Correspondent

CARBONDALE, Ill. — Wheat is taking a back seat to the impressive early corn planting throughout Illinois this season, as nearly three-fourths of the state’s wheat crop is rated “fair” or worse.

Growers, therefore, have about a few weeks left to decide whether to hold on, or make room now for soybeans.

Last fall’s uncooperative weather conditions forced Randy Klenke’s hand. He chose a few weeks ago to destroy the 90 acres of wheat he tried late last fall.

“Last year there wasn’t a lot of wheat that could be put in on time because of the wet weather,” said Klenke, secretary of the Illinois Wheat Assoc. He farms just north of Edwardsville.

“Most of the folks here in the Metro East area generally have decided already what they’re going to do, and most are choosing to destroy their crops,” Klenke continued. “I tried, even as late as it was last fall, but it just isn’t worth saving. Wheat is still a very viable crop, especially in terms of rotation.”

University of Illinois Extension agronomist Emerson Nafziger said, “There are some good wheat fields in Illinois, but not very many. If your plan is to let a marginal wheat crop go to maturity and then to plant double-crop soybeans, you need to consider the risk of trading good row-crop planting conditions now for very late planting of a second crop under uncertain conditions in mid- to late June.”
Nafziger explained that timing is critical right now.

“The key to assessing yield potential now is to count the number of heads per square foot,” he said. “We normally estimate that one head per square foot will produce one bushel per acre. Thin stands tend to produce larger heads, but even at that, many existing stands are not expected to produce more than 30-40 bushels per acre. Whether or not that’s worth keeping depends on an individual’s approach to risk, and the degree of optimism about the chances for good double-crop yields in southern Illinois.”

Actively growing wheat should be relatively easy to kill with herbicides at this growth state. Nafziger advises growers to watch closely for insect larvae such as armyworms that can hatch on wheat plants and then move over to a newly planted crop once the wheat starts to die.

Allelopathy, plant injury caused by chemical substances released as crop residue breaks down, is a concern when a growing crop is killed.

“Even though we often can’t see or measure an allelopathic effect and crops planted in this way typically do very well, it makes sense to move the residue off the planted row so that anything leaching out of it doesn’t reach the newly planted seed or seedling,” he said. “However, it may be difficult for trash movers to push aside all of the crop residue, especially if the wheat crop roots haven’t died yet.”

The goal to place and cover seed in the soil without having crop residue pushed into the seed furrow might be achieved by using tillage if no-till doesn’t work. In some cases, Nafziger said it may be more beneficial to let the killed crop dry up for a few more days if that’s the only way to get good seed placement of the replacement crop.

Last year, about 820,000 acres of winter wheat were harvested in Illinois, according to National Agriculture Statistics Services. Nearly 90 percent of the crop is grown in southern Illinois.