If you bring home one lesson from a field day you can use, the day was probably worth it. Stacey Odom, with the Natural Resources Conservation Service in northern Indiana, attended a field day last week on minimum-till and no-till farming. He brought home a message from Phil Needham, a speaker and long-time crops consultant, that may be worth its weight in gold.
"He was insistent that with these big combines we have today, with 35-feet wide heads and the like, we're not getting the soybean residue spread well enough behind the combine," Odom says.
That one caught me of guard. I thought that with shredders and various spreaders, we had conquered that problem. Odom is convinced otherwise, and says that Needham had the pictures and examples to prove it. The problem, Odom says, is that so much of the chaff and straw, even if it's chopped up, still falls within a relatively narrow width behind the combine, compared to the width of the head. It may not be like the old days when soybean stalk pieces were still bunched up here or there, but even the chaff can cause differences if it's heavier in some places than the others."
We can get it out of there in the spring if we use row cleaners," he says. "Then the ground will warm up. But it doesn't make a consistent planting seedbed all the way across the field."
Odom is also concerned that it could eventually affect soil fertility distribution. If the crop residue falls on, say one-third to one-half of the cutting distance, over time that could have an effect on soil fertility levels in one area vs. another. His theory is that the area where the residue falls will eventually build up higher levels of nutrients, especially if you combine in the same pattern year after year.
As far as he knows, there is no data to back that up. But until he heard Needham speak, he says it really hadn't dawned on him how much of a factor that might be in some fields.
His conclusion is that it will pay to do all you can to chop and spread residue out as evenly as you possibly can this fall. Make sure your spreader or chopper behind your combine is set to spread residue as wide as possible.
One issue that many no- tillers assumed they solved years ago may not be solved at all, he notes. Increasing size of machines, primarily the grain table width, has contributed to a need to rethink this issue.