Crops are maturing quickly in Iowa, as of September 12. What should farmers be doing now to prepare for the upcoming harvest? "One concern I have is we definitely had considerable stress on the corn crop this summer," says Iowa State University Extension field agronomist Jim Fawcett, who covers east central and southeast Iowa. "With the extreme heat and in some areas dry weather as well, you tend to get more stalk rot problems, the more stress the corn is under."
Fawcett is concerned about the potential for stalk rot to develop in many fields in Iowa this fall. "Now is a good time to go out and check some of these fields," he says. "With your thumb and finger, just pinch the lower part of stalk and see if it is mushy or hard. Try to make some decisions about prioritizing your harvesting. Are there some cornfields that look they should be harvested first, to try to prevent lodging as much as possible?"
What about ear rot and related grain quality issues this fall?
There are already reports about ear rot and molds developing on the grain on corn ears in some fields. That problem may get worse. "That's something else farmers should be checking on in their fields," says Fawcett. "That would be another reason to harvest early, if you are seeing some molds or ear rots on the corn out there in your fields."
In particular, watch fields where there has been hail damage this summer. Hail damage would tend to increase ear rot problems, he says. Or if you have insect damage maybe in the refuge acres, whether it's corn borer or the western bean cutworm, the insect damage can increase the incidence of ear rot occurring.
"If you are seeing some fields with more ear rot than usual, you had better take some special precautions now and make sure to dry the corn appropriately as soon as you harvest it," advises Fawcett. "You should probably spend a little money on propane and dry that corn artificially in the bin this fall, rather than try to let Mother Nature air-dry it in the field."
Watch for problems in cornfields that were struck by windstorms
In July a ferocious straight-line windstorm struck a large area of central and east central Iowa, knocking corn down in many of the fields. Several other big windstorms since then have flattened fields in some other areas of the state. A lot of corn was knocked down this year. But most of it has straightened up fairly well, although many of the fields are still goose-necked somewhat. There are issues with that corn in the storm-struck fields that farmers will have to wrestle with.
"With lodged corn, it's going to be more of a headache in harvesting it," says Fawcett. "You need to drive slower than normal with the combine through the field. Some farmers have bought special pick-up reels or other equipment to mount on their combine's corn header to pick up the downed stalks and get those lodged stalks into the combine better. But even if you have a reel, it's not going to be fun harvesting a lot of these cornfields this fall in Iowa."
It won't be a fun harvest in Iowa this fall with all this lodged corn
ISU Extension agronomists say they've seen more lodged corn than usual this year in Iowa. The wind event on July 11 covered over 100 miles from near Ames to Cedar Rapids towards Dubuque, and was 15 to 25 miles wide. There have been a lot of other wind events since then in other areas of the state too.
Fawcett observes that, "This year it's more of an issue than usual for having a lot of corn that's just going to take some extra time to get it combined. You need to take your time harvesting the downed corn once you get into the field, try to prevent harvesting losses as much as possible. You also need to prioritize these fields and try to start harvesting them early to prevent further lodging losses."
How early should you start harvesting the wind-struck fields?
Fawcett recommends starting to harvest the problem fields early, if you can get into the fields to do it. "I suggest you begin harvesting the stressed fields early because you are probably going to see more stalk rots developing in the stressed fields. I would try to harvest these fields early and dry the corn grain artificially instead of letting it remain in the field and trying to dry it in the field."
A lot of corn in Iowa's storm-damaged areas is close to black-layer stage now, if it hasn't already reached the black-layer stage of growth. When the black layer forms in the tip of the corn kernels that means the corn has reached physiological maturity and it won't produce any more yield. "We are indeed now getting close to the end of the 2011 growing season," notes Fawcett.
Iowa corn and soybean growers can't catch a break this year
Southeast Iowa and parts of east central and central Iowa have been hit hard by extremely dry weather this year. And in southwest and western Iowa, it seems like growers can't get a break this year either. All summer many fields along the Missouri River on the western edge of Iowa have been flooded out. Then last week a big storm struck west central Iowa, where corn and beans had been looking quite good.
"We had a stretch of decent looking corn in west central Iowa that had dodged most of the damaging hail and wind so far this season," says Clarke McGrath, ISU Extension field agronomist at Harlan. "I had hoped that some of our corn would push 200 bushels per acre or better. Not any more."
He explains, "On our way home from a great Friday night high school football matchup on September 2, we ran into a viscious storm that hit with heavy rain and high winds and flattened thousands of acres of corn. While it didn't do the soybean fields any favors, they don't look as bad as the corn fields."
While not every field was totally flattened in this west central Iowa storm last week, many fields have large areas where 50% or more of the corn went down. "We have had both stalk lodging and root lodging, and from what we can tell it wasn't really tied to any particular sets of genetics," says McGrath. "Yes, indeed, harvest will test the patience of many growers this year."