Rain makes corn, but corn needs sun
WORTHINGTON -- With rainfall totals ranging anywhere from less than 2 inches to more than 6 inches over the weekend across southwest Minnesota, many area farm fields have taken on the look of lakefront property. Now, farmers aren't just wondering how they will get into the fields to do their spring spraying, they're wondering what to do about the crops that have washed away.
The old adage that corn should be knee-high by the Fourth of July may not come to fruition in some fields this year, as a cool and wet spring hasn't offered the heat units necessary to fuel plant growth. Typically, corn fields are tasseling by early July.
Dusty Neugebauer, precision ag manager for New Vision Cooperative, said farm fields need sunshine -- something they haven't had for a consistent seven-day stretch since the crops went in the ground in May.
"Last week we started to catch up on heat units -- we're maybe 25 to 30 heat units closer to normal," he said.
The stretch of dry days toward the end of last week allowed some farmers north of Worthington to finally get into the fields and wrap up soybean planting.
Ron McCarvel, Nobles County Farm Service Agency director, said there was a lot of planting going on Thursday and Friday. At this point, he hasn't received any reports of prevented plant acres, although his office may begin to see some failed acreage reports come in after this last rain storm. The reports are required to be completed by farmers who have cornfield drown-outs and want to plant soybeans in those areas.
Neugebauer said corn can withstand up to three days under water before the plant dies, but soybeans are more susceptible. After more than a day under water, soybean plants likely won't survive.
"I think we're going to have some replants going on, and that's bound to take us down from full field yields -- maybe 5 to 10 percent under what we thought we'd get for optimum," Neugebauer said.
That anticipated yield loss isn't bad considering what's happening in other areas of the state.
Jeff Coulter, University of Minnesota Extension corn agronomist said southeast Minnesota farmers are looking at prevented plant acres and trying to plant cover crops.
"Overall, the corn in southwest Minnesota is looking far better than in other parts of the state,"
said Coulter. "Assuming the corn didn't get damaged by wind or hail recently, it should be sitting in really good shape." Coulter said.
As for the ponding water, he advises farmers to watch for nitrogen deficiencies in their corn crop.
"There's not much we can do at this point except finish up weed control and scout for disease and pests," Coulter said. "With the rains, it's been difficult to get in and take care of the weeds. The same thing is happening for beans."
Neugebauer anticipates there may be more aerial spraying done later this week as farmers push up against a deadline to apply certain chemicals before the corn crop gets too tall.
Just as the farmers are watching for diseases and fungal problems, they will need to be on the lookout for pests as well.
Bruce Potter, Integrated Pest Management specialist with the University of Minnesota's Southwest Research and Outreach Center at Lamberton, said the "slow spring" with cool and wet weather, while it hasn't been ideal for crop growth, has slowed insect problems.
"Everything's kind of pushed back as far as pests," Potter said. That said, farmers should watch for soybean cyst nematode and soybean aphids -- tiny bugs that can be found on the underside of soybean leaves -- as some have been found on volunteer soybean plants already this year. The wet weather is not conducive for the aphid population, Potter said, while he has reports of nematodes found in some of the small grains.
In corn, Potter said all eyes are on corn rootworm. The cool spring has delayed the hatch, but he expects they will find out "pretty quick" how well the population survived winter.
Potter said if farmers consider the "glass half-full perspective" in regard to recent rains, it's possible the flooding in farm fields helped drown out and kill some of the rootworms.
In alfalfa, Potter encourages farmers to keep an eye out for the alfalfa weevil, and potato leaf hoppers could also pose a problem this year.
With more rain falling on Monday, Potter said farmers just need it to dry out a little.
"Continued wet weather is never good for diseases," he said. "It's bad for insects and good for fungi and bacteria."
With the latest U.S. Drought Monitor to be compiled today, Potter anticipates much of southwest Minnesota will be out of the abnormally dry category.
"We've got more water in the profile than we did last year at this time," he said. "It's not looking anywhere as bleak as it was early on."
Neugebauer said despite the heavy rains in some areas over the weekend, rain is still critical for this year's crops.
"We're still going to need rain in August to make beans and corn," he said.
The hail, however can stay away. One week ago today, hail, some to the size of baseballs, went through portions of Cottonwood, Redwood and Brown counties.
"It's a pretty big area, from Wabasso and Wanda down to Comfrey and Mountain Lake," Potter said, adding that the path was about three miles wide. Despite the hail storm, he anticipates much of the affected crop will be OK.
Daily Globe Reporter Julie Buntjer may be reached at 376-7330.