Dr. Dan Talks Agronomy

The desire to plant early increases each year as research continues to show, when conditions are right, earlier planting can mean higher yields. Everyone hopes for an early window to get the seed in the ground in good soil conditions -- and hopefully in April. There is nothing wrong with that goal, though later planting isn't necessarily a disaster either, and there are many factors besides planting date that can influence final yield.

Planting corn earlier than normal has been popular for some time, and now, planting soybeans almost as early is popular and possible. As growers move to wider planters and multiple planters, they can plant sooner. Emerson Nafziger wrote in the University of Illinois Crop Bulletin, "The main message is that we need to give similar priority (to) both crops in terms of getting them planted on time. For those with more than one planter, that may mean planting both crops simultaneously, as fields get ready to plant. Our long-held idea of planting corn first then starting to plant soybeans requires rethinking and possible adjustment."

Read the full article at http://bulletin.ipm.illinois.edu

Early planting gives the corn plant more time to build leaves and capture sunlight and produce bigger ears. For soybeans, it gives the plant more time to add nodes and branches, which can mean more pods and more leaves to capture more sunlight for more soybeans. Those bushels don't come without some risk, but that can be managed.

WAITING ON WEATHER

The biggest factor for early planting success is weather. Planting at soil temperatures as low as 47 to 48 degrees Fahrenheit isn't a harbinger of disaster if air temperatures are entering a warming trend during germination and moving up into the 50s. While a rainy forecast isn't an immediate risk, rain coupled with an expected drop in air temperature leads to chilling injury and mortality. In those cases, wait to plant until the forecast improves.

SOIL CONDITIONS

Soil conditions are important whether planting early or late. We want soil temperature above 50 F, but soil structure is also critical to accurately place seed without causing surface or sidewall compaction. Soil needs to be crumbly to be fit to plant. A soil can be fit to plant any month of the year. I have drilled rye in December. Kris Ehlers with Ehler Brother Seeds in Thomasboro, Illinois, just planted 2 acres of soybeans on Feb. 22 when soil was fit and 4-inch temperature was 58 F with an air temperature of 70 F. (https://www.facebook.com/…)

SEED TREATMENTS

Besides watching the weather, the next most important decision for early planting is which seed treatments to use. With slower emergence due to cooler soil temperatures comes extended exposure to soil-borne pathogens. That makes a stacked seed treatment, with three or four fungicide-active ingredients and perhaps an insecticide, important. Protecting the seed and seedling from Phytophthora, Pythium and Rhizoctonia is particularly important. And, with soybeans, treating with ILeVO may help mitigate risk of SDS (sudden death syndrome) when early planting. https://www.channel.com/…

POPULATION

We generally don't change planting population in corn when planting early. However, in soybeans, there's growing evidence you can cut back the seed rate population. Dan Froelich, agronomist with Brandt Consolidated, Inc., in Illinois said, "We recommend for April 15 to 30, 120,000 to 130,000 seeds per acre; May 1 to May 15, 140,000 seeds per acre; and after May 15, 150,000 seeds per acre." He added, "By reducing the population, we give plants more space and a larger amount of time to build a bigger factory, thus we need fewer plants."

Early planting in good soil conditions and a favorable forecast tends to favor high yields, but if conditions are cold and wet, don't rush to plant so you are 'done in April.'" Wait until conditions are right. Germination and emergence will be faster, you will have a better stand, and if your other agronomic conditions are correct for the field, you may have the same yield as if planted earlier.

For more about early planting and management, read Bob Nielsen's article at Purdue and Stephanie Porter's article at Burrus Buzz at https://extension.entm.purdue.edu/… or http://burrusseed.com/…

Dan Davidson can be reached at djdavidson@agwrite

(GH/BAS/AG)

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