Reports have come in about concentrated flow leading to gully formation in long-term no-till fields.
In the tillage days one would level these areas annually, basically covering up the problem without addressing the cause. So how do you address this issue without losing the benefits you have built up with long-term no-tillage?
Here are a few tips:
• Don’t till the entire field. Tillage only helps to cover up your mistakes, not fix them. The only tillage justified is to repair the gullies and then to change management to address the cause of gully formation.
• Guarantee high residue cover throughout the crop rotation.
• Plant cover crops immediately after harvest — what we are trying to emulate is the grassed waterway with its massive root system and surface cover that holds the soil in place.
• Don’t kill cover crops early, maintain high residue cover.
• Plant cover crops in the areas of concentrated flow.
• Maintain soil structure by avoiding compaction.
• Plant on the contour. This conservation practice is still highly relevant to avoid runoff following the rows.
• Install a sub-surface drainage system if needed. This may be the solution if the cause of gully formation is seeps and springs.
• Install terraces and diversions to help shorten slope length thereby reducing the potential of gully formation.
• Divert road runoff. Often a gully starts right at the low point of a road where road runoff enters the field or where a culvert channels runoff from above a road into a field. A diversion may be needed to make sure water fans out. A sedimentation basin and possible subsurface drainage may be the solution if the water can be taken to a safe outlet.
Some soil conservationists are recommending farmers put these areas in grassed waterways. With their massive and permanent root system they can help control gully formation.
However, from the farmer’s point of view, it is desirable to avoid putting in grassed waterways. Grassed waterways result in lost production and the inconvenience of having to shut off sprayer booms and planters and drills.
Add to that the expense of maintenance of the grassed waterway and it becomes a costly practice. So whatever the producer can do to protect the soil from gully formation without putting in grassed waterways would be helpful.