Time To Call The Corn Crop What It Is

July 13, 2012 08:04 AM

(News page 4 feature in this week's Pro Farmer newsletter.)

It’s time to quit tip-toeing around the obvious conclusion of the 2012 corn crop.

It’s a disaster.

Friday morning’s rain in Iowa and the western Corn Belt will certainly help corn. Most of the crop in the areas receiving rain Friday morning either pollinated by July 7 or was pollinating as the rain fell. A small percentage of the crop in the area still hadn’t pollinated, but will within 10 days.

But the serious problems are in the eastern Corn Belt. We’ll be surprised if Indiana has a statewide average yield above 100 bu. per acre; Illinois will be a bit better, but probably won’t be above 125 bu. per acre. And everything isn’t “good” in expected higher-yielding areas of the central and western Corn Belt. A few field checks around the Pro Farmer headquarters in Cedar Falls, Iowa, revealed an unexpected problem — way too many blank stalks in what are traditionally very good fields. No amount of rain will fix that problem.

Blank stalks caused a major yield drag on 1995 corn across the Midwest. Hot temps (day and night) at pollination and shortly before pollen shed got the blame in 1995, and will get the blame again this year.

Plenty of ‘weird stuff’ in this corn crop —

Dead “green” leaves: This was first mentioned by Crop Tour crop reporter Byron Jones. We talked with Farm Journal Agronomist Ken Ferrie last week and he explained dead, green leaves at the bottom of corn plants are the result of extreme heat. Potash is the key ingredient that tells a plant to roll leaves to conserve water. Under stressful conditions, potash is pulled to the top of the plant and if the plant isn’t uptaking any water/nutrients, the lower leaves run out of potash and don’t get the signal to curl. Those dead, green leaves died from heat exposure.

Extra-long silks: If you have corn with long silks that are still green, that means viable pollen hasn’t yet landed on them. Silks will grow up to a half-inch per day, so if you’ve got five-inch-long silks, they may have gone 10 days without being pollinated. It could mean all the pollen had been shed before silking, or it was sterile.

How long did corn “fly the flag?” Some crop-watchers have shared how impressed they were that plants seemed to protect the tassel by keeping it wrapped in the flag leaf for up to 10 days during extreme heat in early July. Don’t be impressed. The flag leaf was rolled around the tassel, but it still may have shed pollen... right into the whirl.
Stacked nodes: Short, green corn that looks good from the road may have nodes sitting on top of each other. That might be okay, but it might also make it nearly impossible for plants to shoot an ear. Or, the ear might be compressed. We’ve seen some of this in northeast Iowa. It’s resulting in 2- to 3-inch ears.

Still too early to call the bean crop —

Soybeans in some areas have undoubtedly suffered irreversible yield loss. But soybeans can be downright “ornery.” We’ve said this many times over the years: Soybeans like stress — but it’s got to be the right amount of stress at the right time.

Severe stress after blooming is rarely good. Stress in the early stages and just ahead of flowering will compact nodes on the stem and actually “tells” the soybean plant to aggressively bloom and set pods. Give the crop a drink at the R3 stage of development after moderately stressful vegetative development and beans can yield surprisingly well.

Once pods start to develop, drought stress can abort pods and reduce the number of beans per pod. Stress late in plant development can reduce the size of beans inside the pods.

Back to news


Spell Check

No comments have been posted to this News Article

Corn College TV Education Series


Get nearly 8 hours of educational video with Farm Journal's top agronomists. Produced in the field and neatly organized by topic, from spring prep to post-harvest. Order now!


Market Data provided by QTInfo.com
Brought to you by Beyer