Minimum tillage short stubble risks damage to tyres

According to Continental’s agricultural tyre specialist Tom Godwin: “Lower or shorter stubbles protrude at sharper angles, with the potential to damage tyres because the stalk will not be pushed over, and can instead dig in. This can cause damage to the lug and, at low pressures, the sidewall, as it bulges under the weight of the tractor.”

Min-till cultivation requires the stubble to be shorter in order to plant the following crop with minimal ground disruption. This, combined with the improved genetics of cereal crops, can leave very strong stubbles that can cause significant damage.

Mr Godwin continues: “Using a tyre with a wider lug that leaves less room for stubble damage is one way to mitigate against stubble damage but fundamentally tyre choice and pressure will play a bigger part.”

Continental has developed its d.fine lug design with 5% greater lug coverage to protect the area between the lugs. The manufacturer has also added a nylon layer beneath the tread to help make it more flexible. In short stubble, Mr Godwin advocates running at higher pressures than would normally be expected for field work.

“Harvest is a rare example of when it can be beneficial to run tyres at higher than normal pressure and we recommend up to 0.4 bar. When the ground is already hard, having a tyre at very low pressure will cause the tyre wall to bulge. If this happens when the tyre is constantly being attacked by stubble, it presents a weakness that can lead to tyre failure,” he says.

Running wide tyres at low pressures increases the risk of tyre failure in short stubbles Having more air in the tyre also helps to keep it cooler in the hotter conditions faced during harvest.

Increased pressure tightens the tyre wall, making it taller and less prone to stubble damage. However, with higher pressure comes the risk of soil compaction.

Mr Godwin says: “It is a tricky decision to make but if a tractor or harvester is doing long hours, heat build-up can become an issue. We therefore suggest that utilising tramlines and headlands for field travel and loading is important to reduce compaction.”

He further suggests that few manufacturers are offering warranties against stubble damage, but says Continental still supports farmers with its tyres made since 2017.

“We are the only premium manufacturer offering a 10-year warranty that includes three years’ stubble damage cover. This is for tyres made in our Lousado manufacturing plant, from 2017, that feature both d.fine and N.flex technology that we believe will be able to better handle the threat of stubble damage,” Mr Godwin concludes.