If you have on-farm grain storage, irrigation capability and/or have had ample rainfall this season, plenty of combines with corn headers are parked in the shed and your crop didn’t freeze on Easter and have to be replanted, you certainly don’t have as much to worry about when fall corn harvest rolls around, save for a wayward hurricane or two.
But chances are your situation is not quite perfect, and as such, you have a few challenges ahead as Mid-South producers harvest what is expected to be a huge corn crop. How you manage your crop from here through harvest will determine how much profit you add to your bottom line, according to the experts.
This year, most concerns with the corn crop begin and end with water.
Dry weather has had an impact on the Mississippi crop, according to Erick Larson, Mississippi State University’s Extension corn specialist. “Our storage soil moisture levels have been extremely low because we haven’t had enough rainfall to replenish them. This has made the crop dependent on supplemental water.”
While yield potential is good in irrigated corn, yields are likely to be variable. Larson explains that drought stress makes even small mistakes in irrigation timing costly in terms of yield. “Plus there are some limitations on how much water we can put out, especially in our center pivot irrigation systems. This makes it difficult to keep up with corn water demands without help from Mother Nature.”
According to Larson, much of the Delta crop is fairly consistent in age except for the usual differences due to latitude. Likewise, the high amount of drought stress in the mostly dryland Hill crop “is going to accelerate the maturity process and harvest may not be as spread out as much as it normally is, depending on rainfall the rest of the season.”
In other words, Mississippi could be looking at a big crop maturing in a relatively short time frame. This is sure to stress handling and transportation systems, meaning corn may have to spend more time in the field after maturity. Stalk strength is a crucial factor in helping corn weather a storm or high winds.
Timely irrigations will maximize yield and maintain good plant health until physiological maturity, according to Larson. “Terminate the crop at the correct time, so you don’t lose yield potential at the end of the season. If you terminate water too early, the crop will remobilize energy out of the stalk to fill out the grain on the ear, reducing the quality and strength of the stalk.”
Producers will also have to do a good job of managing corn that was replanted due to a freeze in early April. In many of those cases, “maturity is pushed back into a time period where it’s more likely to endure late-season drought stress, which could reduce yield potential, promote aflatoxin development and delay harvest. On the other hand, it may spread the harvest out, which may improve the elevator’s ability to handle grain.
Aflatoxin is usually more apparent in corn that has been under an extreme amount of stress, “so growers with irrigation capability need to maintain their irrigations so the crop stresses as little as possible over the course of the season.”
Producers who hire custom harvesters may find the going tough, too, Larson notes. “If somebody owns their own combine and the elevator is closed or lines long, they can afford to wait longer than a custom harvester. A custom harvester wants to get the job accomplished and move on. They can’t afford to wait.”
Because the crop is going to take longer to harvest, “growers may want to start harvesting earlier and endure a little bit of dockage on the front end of harvest.
“If you wait until the corn reaches 15 percent moisture, remember that you can lose a significant amount of profit by harvesting at less than 15 percent moisture. “You also expose the crop to harvest losses from stalk lodging due to wind or third generation Southwestern corn borer damage on non-Bt hybrids.”
Corn reaches physiological maturity at somewhere around 30 percent moisture and dries down to a level safe for long-term storage at somewhere around 15 percent moisture. Average drydown is 0.6 percent of moisture per day, which normally takes about 25 days. Drydown occurs more quickly immediately after physiological maturity, but begins to slow as the plant gets closer to ambient conditions.
According to Angela Thompson, Tennessee Extension corn specialist, the honeymoon with corn is over for many first time producers in the state, and perhaps others. “Many of them have told me they will never grow corn again.”
The fact is cotton’s drought tolerance would have handled this summer’s dry weather much better than corn and would not have been in the ground and growing when an Easter freeze hit the region.
West Tennessee’s mostly dryland corn crop has had less than optimal rainfall through most of June, which could negatively impact the quality of pollination. “We expect our yields will take a plunge. We’ll check ears in a few weeks to see what pollination is looking like. Hopefully, we’ll get some water, soon.”
Thompson said that many elevators “are confident they can handle most of the corn brought in. But I expect there will be longer lines at the elevators this year.”
Thompson is recommending that growers with severely dry corn try to harvest it at a little higher moisture, around 18 percent. “Obviously, we don’t want to leave stressed corn standing in the field for a long period of time.”
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