Sioux City Journal, IA
06-05-07
Weather pains put yellow streak in corn crop
By Tim Gallagher, Journal staff writer
IRETON, Iowa -- Ron Muth was one of few farmers conducting weed control in
Sioux County Monday afternoon.
The wind and rain accompanying yet another cold front -- there seem to be three
of them daily -- didn't alter his chemical application plans.
Why? He wasn't applying chemicals.
"I'm doing something I haven't done for 30 years," said Muth, who pulled a rotary
hoe across corn planted May 25. "This is my first year at raising organic corn. I'm
putting my toe in the water with 26 acres."
Toe in the water? The expression foreshadowed a cool downpour that Muth
braved without cab protection. Rains like that, according to one crops expert,
have areas of corn across Northwest Iowa looking a bit yellow.
"There is some concern about corn that is yellow as it's emerging," said Joel
DeJong, a crops specialist with Iowa State University Extension.
A couple of reasons:
No. 1: Lots of Siouxland corn was planted in wet conditions. The nodal root
system which sustains the plant throughout the season began growing as the
weather shifted, becoming hotter, drier and windier.
"It was so hot and windy, they didn't do well," said DeJong, who is based in Le
Mars.
No. 2: Side walling. Two disc blades form a "V" where the corn seed drops into
the soil. If done in moist conditions, side walls around the seed form and can
harden to the point of stunting nodal roots. It's hard for nodal roots to break
through.
"If we slow roots during that time period it doesn't show up then; it shows up
later," DeJong added.
Sidewall impaction problems and weaker nodal roots result in inconsistent fields.
Several rows can look green and robust, while others appear yellow and small.
DeJong estimated some corn plants have roots two feet deep, while others have
roots only 2-3 inches deep.
"Any plant that's behind now has probably given up a little yield potential," he
said.
Rain, rain, every day
What's making matters worse is the current weather pattern, which keeps
chemical applicators idle. It's tough to spray for pest control when it rains daily; or
when wind whip up to 30 miles per hour.
"It's rained every afternoon for the past six days and in between the wind blows
so hard it's tough for those guys to get their fields sprayed," said Paul Kassel, a
field specialist in crops for ISU Extension out of Spencer. "Fields planted with
Round-Up Ready Corn are slated to get Round-Up, but the weather hasn't
cooperated."
Fields not sprayed, according to the Iowa Field Office of the National Agricultural
Statistical Service, are developing weed problems.
"It's a little weedy as it's too windy or, like today, there's a chance of rain so
they're a little skittish about spraying," said John Becker, general manager of
Farmers Cooperative Elevator at Craig, Iowa.
That said, Becker believes the stands look good. So does Kassel. Agronomy
Marketing Manager Kurt Ross of Western Iowa Co-op in Hornick said farmers
south of Sioux City are just relieved to have their corn in the ground.
"The corn is up," said Ross, who serves an area that barely averted a planting
catastrophe with incessant late spring rains. "Limited corn replanting was
needed, but not as much as originally thought. The corn survived better than we
thought it would."
While the corn looks late, it still looks good, he said.
Muth's organic corn looks late because it is late. He dodged rain to get it in the
ground two weeks ago. Most of the organic corn has barely emerged, lagging a
neighbor's conventional corn planted at the end of April.
"You plant organic corn later as your corn germinates quickly and then you get a
jump on the weeds," he said, hopping atop his tractor. "If you do it right, it's worth
a lot of money."
Muth's corn and organic soybeans will be sold this fall in Omaha. His free-range
meats and organic vegetables are sold year-round at the local foods market on
Floyd Boulevard in Sioux City.
Digging up a tiny corn plant, Muth surveyed his 26 acres of organic corn and
compared it to his conventional rows to the south.
"At this stage of the game we just need more sunshine," he said. "I'm not going to
complain about the rain. We were dry here the past five years. Just let it rip and
one day it will quit."
The forecast calls for rain chances Wednesday and Thursday, accompanied by
wind gust of 35 to 50 miles per hour.
Pair of 93s
The Iowa Field Office of the National Agricultural Statistical Service reports 93
percent of Iowa's corn has emerged and 93 percent of Iowa's soybeans are
planted.