The weekly weather and crop survey released by Iowa Ag Statistics Service on May 7 shows 53% of Iowa's 2007-corn crop is in the ground. That's a considerable jump from only 14% of the planting completed by April 30.
"At the beginning of last week, it finally got dry enough so farmers could make some real progress on corn planting," says Harry Hillaker, state climatologist for the Iowa Department of Agriculture and Land Stewardship. "But by the end of the week - over this past weekend--we had heavy rains in much of the state. Now we need dry weather so farmers can get back into the fields."
This spring it's "planting & waiting"
Warm, sunny days at the beginning of last week allowed farmers to get into fields and make significant progress. Fields that were planted earlier this spring are experiencing some soil crusting which has slowed corn emergence. Last week ended with more rain on May 5 and 6, stopping planting and causing flooding and erosion. Some fields will be replanted due to silt build-up and erosion.
The moisture helped pastures recover from frost damage but made feedlots muddy. Strong winds and tornado damage in some areas of Iowa this past weekend caused serious damage to livestock facilities and farmsteads.
There were 3.8 days suitable for fieldwork, compared to 3.0 days last year at this time. Topsoil moisture now rates zero percent very short, zero percent short, 44% adequate, and 56% surplus across the state. Subsoil moisture rates zero percent very short, zero percent short, 58% adequate and 42% surplus.
Heavy rain this past weekend
As of May 6, oats planted are 93% complete, 8 days behind both last year's 99% and the 5-year average of 99%. About 53% of oats are emerged compared to last year's 75%. The condition of the oat crop is zero percent very poor, 2% poor, 31% fair, 57% good and 10% excellent. Corn planting, at 53%, is 1 week behind last year's 78%. Fertilizer application, at 90%, was 3 percentage points below both last year's and the 5-year average of 93%.
Pasture and range condition rates zero percent very poor, 7% poor, 31% fair, 47% good and 15% excellent. There are some reported losses of young livestock due to the wet, cool weather.
Up to 6 inches of rain fell over the weekend of May 5 and 6 in western Iowa, and the Des Moines area in central Iowa received up to three inches. Some areas of the state won't be able to resume planting until after Mother's Day.
Some corn is starting to emerge
Larry Beeler, who farms near Peru in south central Iowa, reports 5.25 inches of rain this past weekend. On the other hand, in Scott County near Davenport along the eastern edge of Iowa, farmers were planting corn on May 7. They missed the weekend downpour that drenched much of the rest of the state.
"There were farmers in some areas of Iowa last week that were able to plant 4 to 5 days before the rains moved in," says Iowa State University Extension agronomist Roger Elmore. "Corn planted earlier this spring is starting to emerge now. Around Ames in the central Iowa, quite a bit of corn is coming up. All over the state, we are getting reports of some corn that is up and emerged."
There is some variability in those stands, however, due to the soil crusting. Some farmers are rotary hoeing the corn to bust the crust.
"Iowa can still get the balance of the 2007 corn crop planted without much yield penalty," adds Elmore. "Corn yield potential starts dropping off after mid-May, and declines rather dramatically from that point. Thus, we've got another week or so to get the corn crop planted in Iowa."
When can fieldwork resume?
"Just when you can get back into the field depends on how much rain you received this past weekend," says Elmore. "If it's 4 to 5 or more inches, it's going to take a week or so for fields to dry enough so you can plant. Six days at least. But if you only received an inch of rain this past weekend, it will depend on what happens tomorrow. If the rain stops and we get some wind and warm weather, you could be in the field again within three days."
What about the locations in the state where fields are flooded or have ponds in them? Will those field areas have to be replanted? Corn that's been planted can't take more than a couple of days of water sitting on it. Maybe as many as four days - if the corn is emerged, he says.
What about switching hybrids - to shorter season corn? "It's too early to think about that," says Elmore. "It's only May 7. You have another three weeks before you would have to worry about switching to an earlier maturing corn hybrid."