The Clinton Herald, Clinton, Iowa

July 9, 2013

Wapsi River waters damage corn

By Mary Lou Hinrichsen
Herald Staff Writer

---- — DeWITT — “We have two fields that will have damage from the Wapsi River,” farmer Joe Dierickx told the Clinton Herald for this crop update.

“This is the fourth time this year it’s gone into our fields. One field will lose 30 acres of corn and the other one will lose about 50 acres, “ he said. “The late planted fields are growing well but are behind in development. Normally we would be seeing a few tassels by July 4th. Now we are at least two weeks away from tassel. The soybeans are growing rather slow, as ‘they don’t like wet feet’, as the saying goes. The rain we had was needed, as it was getting dry for the shallow roots on corn and soybeans because of early soggy soils.”

In the northeast area of the county, farmer Dustin Johnson said all of his crops “have been growing fast with the warm humid nights. But,” he said.”As you drive through the county there are a lot of uneven fields and there are huge differences from field to field. The good news is that it will spread pollination timing out, but will put the later corn at high risk of excessive heat.

“I am anticipating fungal and stalk rot problems this fall and am treating the crop with fungicide to protect the plant as much as possible,” he said.

Virgil Schmitt, Iowa State University’s extension field agronomist for Clinton County told the Herald, “I’ve had my first call about Japanese Beetles — from the DeWitt area — so they are starting to emerge. It is unclear whether this will be a big or small year for them. Japanese Beetles emerge from the soil over a period of about six weeks, which makes it difficult to manage a large population.

“You can spray for them, but after about two weeks the insecticide is gone and more are still emerging from the soil. It is tempting for producers to spray as soon as they see a few, but often that means they will need to spray again later. It is best to wait until the numbers warrant spraying — if and when that happens.

“Spray when the loss of leaf over the entire soybean plant is 20 percent or greater, or if the beetles are keeping the corn silks clipped to within 0.5 inch of the end of the corn ear prior to pollination. Once pollination has taken place, the silks have done their job and we don’t care if the beetles chew them right down to the end of the ear.”

Schmitt said Sudden Death Syndrome is a possibility for soybeans planted into soils that became cold and wet immediately after planting.

“If the infection happened, the symptoms will start to show up in late July or August. Unfortunately, there is nothing that can be done about it for the 2013 crop year.”

But there is something farmers can watch for as soybeans begin to flower. That is apothecia of white mold.

“Apothecia are essentially miniature mushrooms about half the size of your little fingernail,” he said.

If farmers find those, Schmitt said, they can spray either a fungicide or Cobra or Phoenix herbicides. Those two herbicides seem to stimulate the immune system against white mold, he said.