Your high-yielding 2010 corn crop starts now—right now—with an in-field checkup.
Corn roots can tell you how to set the stage for a bin buster next season by removing the dense, impenetrable layers of soil that restrict water movement and root growth.
By scouting fields, digging soil pits and finding soil density problems now, you can plan how to fix them using vertical tillage next fall, explains Farm Journal Field Agronomist Ken Ferrie.
"If you don't correct soil density problems, they'll hang around, limiting yield, until you do,” Ferrie adds. "Often, we'll find a tillage layer in a field and the operator will say, ‘It can't be from tillage; I didn't do any this spring.' After we talk some more, he'll remember he worked it wet the year before.”
About now, you're probably thinking: Sure, scouting for density issues sounds like a good idea, but, wait a minute, how am I supposed to examine 2,000 acres of corn? The answer, Ferrie says, is to do some homework before you head for the field and prioritize the areas you need to scout.
The first thing to consider is that not all soil density changes are man-made. Some occur naturally.
Examples of natural density issues include sand lenses and hardpan layers that are too deep to reach with tillage equipment and soil types, such as Bryce and Swygert silty clay loams, which are common in Illinois. They are rich and black on top, just like highly productive Drummer and Sable silty clay loams. But unlike the deep uniform Drummer and Sable soils, the texture of Bryce and Swygert changes about 11" below the surface. There, the soil is underlain with a near-impenetrable layer of blue clay, which makes it almost impossible to drain or irrigate.
"You can't do much about natural density and texture problems, but you must know where they are so you can respect them and farm them accordingly,” Ferrie says. "You can learn about your soil types by studying soil survey descriptions.”
Tillage records. The second tool you need for efficient scouting—and one of the most important—is tillage records. "If you didn't record tillage information this past spring, sit down with your employees and reconstruct it now before the information fades from your memories,” Ferrie advises.
"Of the compaction issues I work with, more than 70% result from the first tillage pass in the spring,” Ferrie says. "Of course, you always try not to work fields in less than ideal conditions, but sometimes you have to in order to dry them out. Make these fields and the ones you rutted up with the combine the previous fall top priority for summer scouting.”
- Summer 2009