By ANN HINCH
Assistant Editor

AMES, Iowa — As rain continued to pelt this part of the Midwest and upper South last week, many growers had flashbacks to last June’s flooding.

Whether it’s the worry of having to replant corn or not being able to get it in the field at all, there’s plenty to concern farmers. As of last week, Iowa growers were 81 percent complete, far ahead of other Midwest states this year. For some, the rain sparked concerns that fields might need replanted.

But last year also proved much of the corn out there can flourish in unfavorable weather. Dr. Roger Elmore, extension corn specialist at Iowa State University, said Iowa planting was two weeks behind at this point in 2008, the crop was flooded in June and faced drought in late summer – and still managed to produce the state’s third-highest yield on record.

“All those rules on planting dates and all those rules of thumb are broken,” he said. “So don’t get discouraged over planting dates, is the story here.”

Still, caution pays off. Dr. Emerson Nafziger, extension agronomist for the University of Illinois-Urbana, said while growers usually want to plant corn before the end of April, more harm than good may come if it’s too muddy.

While this is the slowest planting he’s seen in Illinois in 16 years, he said the region usually warms up and dries faster after mid-May. Right now, growers still have a good chance to get their corn in the ground.

“It’s almost never not worth (planting),” he said for even late May.
There is no “floodproof” corn seed, since he said researchers don’t generally spend time breeding for such extremes, but he explained many varieties are genetically selected for good emergence.

Elmore said there are corn varieties that can be without oxygen for longer than others, which is a key problem with saturated soil. There is no seed, though, that can grow without oxygen. As for losses, Elmore’s research indicates all fields average between 3-7 percent non-germinating seed in a good year.

“Some are losing 3 percent, some are losing, believe it or not, up to 10 percent,” he said of Iowa fields, adding he personally could live with 5 percent.

He cited recent ISU corn planting research that looks at planting dates and number of plants per acre to determine likely maximum yield, with a baseline 100 percent yield at 35,000 plants per acre planted between April 20-May 1. He said in Iowa, farmers plant approximately 30,000 seeds per acre and the trend for some years has been to increase that by 400 seeds annually.

As of May 20, the best possibility seems to be planting between 25,000 and 45,000 seeds per acre, which could yield up to 83-87 percent from those plants. As June 1 draws closer, that possible maximum yield drops to 67-70 percent. Approaching June 10, it sags further, into the 50 percent range.

Mark Lawson is an agronomist for Garst Seed Co., affiliated with Syngenta, whose service area spans Chicago to Cincinnati. His advice is to get the planting done before going back to look for spots needing replanting, since it is a better use of time and resources – and it gets corn in the ground sooner.

“We can plant so fast now,” he said. “And no-till has helped a lot.”
He would just plant seed now as weather allows, and go back later to sidedress with fertilizer and herbicides.

 “We can safely plant (standard 112-day) corn through June 7 in central Indiana, before changing hybrids.”

Replanting
Lawson was planning to visit two Ohio customers this week in Preble and Pickaway counties whose early-planted corn has suffered from flooding to help them determine whether to replant.

“Sometimes you replant just because you want it to look nice,” he said, “but in this day and age, you have to watch your pocketbook.”
There is also the problem of pests to consider. Some corn underwater in Indiana and Ohio is being attacked by cutworms, but he said it’s not much. Pest pressure is much worse in Kentucky, where he said some farms are experiencing as much as 30 percent stand loss due to cutworms.

He explained the damp, cool, cloudy weather has been “a perfect storm for the cutworm population.” What has saved much of the Midwest so far is it hasn’t planted nearly as much corn as Kentucky. In fact, Lawson advised growers to use their downtime to check fields for cutworms, armyworms, seed corn maggots and even slugs.

Early last week, corn was just emerging north of Ames. “New shoots breaking through the ground is one of the most beautiful things for a corn guy,” Elmore enthused. He advised growers wondering about replanting to look for patterns of problems in their fields: gaps, malformations in stands, strange row patterning. In a suspect row, he would dig in to look at the seed and root system of a plant for clues – advising, of course, that first one must know what a good system looks like.

As for Illinois, the situation is good news/bad news. “We haven’t had much replanting needs, because we haven’t had much planting,” Nafziger pointed out. Nevertheless, he advised growers to look for lack of stand within rows of emergence, or odd stand emergence such as a corkscrew pattern.

Alternatives
Lawson said faster-maturing corn is an option if planting goes to as late as June 12 in most of the Midwest. Beyond that date, however, his personal opinion is to plant soybeans – corn seeded after that date invites worry about August rains and early fall freezing.

Corn futures have risen to reflect late planting and the possibility of higher federal ethanol mandates. During the first two weeks of May, May-December futures rose approximately 13 cents across the board. For soybeans, the May price for old beans jumped 48 cents over the same period; July, 38 cents; and in the fall, over a dime. Lawson said many grain elevators are taking a wide basis on fall soybeans. Nafziger said soybeans are attractive as an alternative, but he doesn’t predict a “big surge” in their planting, and thinks there’s still a lot of corn to be seeded in 2009.

Lawson, a self-coined “eternal optimist,” said if growers can plant corn before June 1, so long as the crop receives adequate moisture and heat after that date, it will do well.

“This isn’t the worst thing that can happen,” he said, adding he’s been growing corn since 1964. “I’ve seen it worse.”