As manufacturers churn out larger and heavier machinery to increase capacity, no-tillers are being challenged to preserve soil structure and avoid the yield consequences of compaction in order to meet growing global crop production demands.
Even though no-tilled fields are usually more resistant to compaction than with other tillage systems, reducing tire pressure to compensate for field conditions can be a preventive step to reduce the risk of soil degradation even further — and boost yields, says Peter Mills, deputy vice chancellor at Harper Adams University, in Shropshire, England.
According to research presented by Mills at a recent Michelin field event in Ladoux, France, about 45% of a no-tilled field is driven on by a tractor tire every year. This compares favorably to 86% of a field being driven over in a conventional-tillage system, but even in no-till the tire traffic can take a toll on soils.
“We know that one pass of a tractor wheel causes 90% of the compaction damage to soil,” Mills says. “That inhibits water infiltration and makes life much harder for the crop to emerge and grow.”
A comparative demonstration at the field event revealed visual indicators of the difference tire inflation and technology can have on soil structure.
Using a 1-meter-deep soil pit of layered black clay and construction-grade red gravelly sand, a tractor with a 10,000-pound load made two independent passes across the pit’s surface — one with Michelin’s MultiBib tires, inflated to 22 psi, and the second with…