by Matt Hagny
I’ve spent a lot of time over the years urging no-tillers to avoid compaction and ruts with their equipment by using larger, low-pressure radials (see article) or tracks on everything that might be in the field when it’s wet. For the most part, the long-term no-tillers who have done this came thru last fall’s exceedingly wet harvest in very good shape—almost no discernible rutting (on fields that’ve been low-disturbance NT for 20ish yrs). Those who hadn’t yet caught on about the bigger tires and tracks, or who had less history of NT, now face some difficult decisions on how to correct the issue going into spring planting.
If the tracks are mostly just depressions without any soil thrown or squished off to the side, I favor ignoring them—just do your future field operations parallel to the tracks. Eventually the soil restructures itself and the depressions become smaller.
If mud was squished out of the track, then some soil manipulation (a.k.a. tillage) is probably best in those areas of the field. As a reminder, any tillage is going to further degrade the soil structure, so we want to engage the smallest volume of soil possible while still making some semblance of a smooth planting surface. (If the field was first-year NT, then I’d be more willing to engage a bit more soil to get back to a smooth field—while also making plans to avoid ever tracking it up again; the more years in NT, the more reluctant I’d be to do any more than absolutely necessary.)
As to the Rules of Engagement, the wetter the soil is when you undertake the remediation, the more damage you will do to the structure. Spring isn’t known for being dry in most of these areas, so good luck getting the opportunity—you might be forced to do the absolute minimum of knocking down the lumps squished or thrown out of the tracks, doing just enough to make it plantable. Whatever you do, don’t create more compaction layers by running tandem disks or other implements through wet soil. Those will haunt you.
Here’s advice on dealing with ruts from John Grove, soil and agronomy scientist from U.Ky (and longtime no-till advocate): “Depends a bit on depth. If shallow, I recommend they be left alone—plant through them and let roots sort things out. Growth might be reduced some, especially if things get dry later in the year, but usually not worth the effort to take out. If deeper, and especially if some soil was pushed out and is available to fill in, I like a field cultivator set to get a couple of inches below the depth of the rut. Take things at an angle to the track, but weaving gently back and forth—just as the edge of the cultivator reaches the edge of the rut track drift back across the rut track until reaching the other edge with the cultivator. Have to be gentle due to the side force on the cultivator.” Grove emphasizes that the remediation should be done with sweeps or chisel points, and not a disk (he’s not fond of ‘vertical tillage’ tools either). If the ruts are more than a few inches deep, it’s going to require a chisel plow (either with points or sweeps), subsoiler, or something more robust than a field cultivator.
I’m leery of attempting to get below the depth of the rut with a wide implement, as this results in a large volume of soil disturbed, and will make the area more prone to rutting in the future. I tend to prefer just knocking the lumpy edges of the rut down, for which a field cultivator works well because it tends to not penetrate very well (I run it so the sweeps or points are exactly at the soil surface in-between the ruts, so I’m really not disturbing any volume of soil at all). It may not grow much of a crop in the ruts the first year, but it will tend to prevent future rutting and accelerate recovery of soil in that area. However, a happy compromise would be to remove all the shanks from your implement (chisel plow, subsoiler) except the 2 that match the combine ruts. After you lift this part of the rut, you then will still need to come back and smooth it all down with that implement or another with more sweeps, and set them to run at the soil surface of what was unaffected by rutting. Note that if it rains a lot, the soil will collapse/run back together, and the ruts will still be visible—because they have less structure.
And while you’re doing this remediation, you’ll have plenty of time to think about getting bigger tires and tracks under your equipment going forward—you need this not only to prevent rutting, but for compaction minimization (compaction is more of a yield-killer than most people realize).