Seed companies are telling farmers it's not time yet to switch to shorter season corn hybrids. Wet and cool weather during April has delayed corn planting in Iowa and other areas of the northern Corn Belt this spring. But planters are finally starting to roll and corn is being planted in early May.

Pioneer Hi-Bred agronomists are trying to keep farmers from unnecessarily switching to lower-yielding, earlier maturing corn hybrids. Pioneer sales representatives are urging their farmer-customers to take advantage of opportunities to get the crop planted as the ground gets dry enough, before changing seed varieties.

"You don't want to prematurely switch to lower yielding seed varieties," says Paul Schickler, president of Pioneer Hi-Bred. "Stick with the maturities that are adapted for your area."

Don't change to earlier hybrids until late May

Pioneer agronomists say their company's latest research results show farmers in Iowa can plant full-season corn hybrids as late as May 26-29, giving farmers more time to plant the highest-yielding varieties than was previously the case.

A billion bushel drop in corn stocks this year has put more pressure on farmers to produce a bumper crop in 2011. Any problems with the crop this spring and summer could send corn prices soaring even higher than the $6 to $7 per bushel the market is currently offering, which would lead to a further squeeze on livestock producers and ethanol plants.

Planting delays this spring have some people worried about lost yield potential, but farmers in Iowa still have time to plant corn without suffering a significant yield drop, says Schickler.

Adapted maturity corn provides best opportunity

Agronomists from Monsanto are giving similar advice to farmers. Hobart Beeghly, vice president of product management for Monsanto, says: "While every planting decision is unique, our local seed dealers and agronomists are working with farmers and advising farmers they still have time to take advantage of the opportunity that planting appropriately adapted corn hybrids provides."

The Monsanto official adds, "The window is still open until mid-May or so for planting corn to capture the yield potential of full-season hybrids."

Iowa State University agronomists say corn planted in Iowa before May 9 is in the 98% yield window and before May 18 is in the 95% yield window. Long season and mid-season hybrids have good yield potential yet. ISU yield data doesn't suggest switching to shorter-season hybrids until mid-to-late May. ISU agronomists are suggesting that farmers use patience in evaluating stands of corn that have already been planted, and don't rush into changing corn hybrids.

U.S. needs to produce big corn crop this year

Corn stocks are currently at their lowest level in the U.S. since the mid-1990s and the delay in planting has pushed corn prices higher. Schickler says it will likely take up to four years to rebuild stocks sufficiently to remove some of the riskiness and volatility in the marketplace.

Also in a speech last week, Schickler said he believes there is no need to rollback U.S. ethanol mandates, which require a certain amount of ethanol to be blended with gasoline each year. Rolling back the federal ethanol mandates would discourage development in the biofuel industry, especially the next generation biofuels, such as cellulosic ethanol. "If we are going to make a dent in reducing the demand for fossil fuels, we must have consistent policies that make those investments predictable in the future," he says.

Vilsack is still optimistic about corn crop

Meanwhile, U.S. Secretary of Agriculture Tom Vilsack is expressing confidence that farmers will grow enough corn this year to help rebuild the nation's stocks, despite the wet, cool spring weather that has delayed planting in the Midwest.

"Fortunately for us the technology of corn production has improved to where we still have time to get the 2011 crop in the ground without significant loss in yield potential, and our farmers have the opportunity to get a good return on that investment," he says.

Studies at Iowa State University as well as studies by seed companies show yields don't start dropping much for corn that isn't yet planted until after the middle of May. "I'm still confident we are going to meet the needs for corn that we have in this country," says Vilsack, a former governor of Iowa.