Fall Tillage After Wet Harvest Conditions


Wet conditions at harvest usually means getting the grain out of the field under less than desirable conditions.

Some guidelines for managing soil compaction during a wet harvest include:1

  • Starting harvest on well-drained soils to avoid compaction.
  • Estimate soil moisture by collecting a handful of soil from an area between ruts and 2 inches above the operating depth of the tillage tool and form it into a ball. Throw the ball on the ground. If the ball remains mostly in tact the soil is to wet to till.2
  • Soil may be less sensitive to compaction if there is some frost present in the soil.
  • Use surface or shallow tillage to reduce ruts in the field.
  • Reduce equipment tire pressure and axle loads. Axle loads above 10 tons can cause subsoil compaction.
  • Increase tire footprints by using floatation tires, duals, and reducing tire pressure. Check inflation tables to determine minimum allowable tire pressures.
  • Use the same travel patterns when possible. This will help contain and reduce soil damage.
  • Cover crop and freeze/thaw conditions in winter can help address shallow compaction. Subsoiling may be necessary if compaction is deeper than 6 inches in the soil.

Harvest traffic on wet soils can cause ruts and soil compaction. Ruts left in the field can create an uneven soil surface and affect seed-to-soil contact during planting. Managing traffic patterns in fields can help minimize the detrimental effects of ruts and soil compaction.

Traffic pattern management usually involves uniform machinery sizing and use of global positioning system (GPS) guidance of equipment. Maintaining repeated traffic patterns between transport equipment and the combine can help reduce soil damage.

Smoothing out ruts is necessary to provide a uniform seedbed at planting time but tillage can have negative consequences for compaction. Try maintenance tillage in rutted areas rather than the whole field.

  • Shallow, vertical tillage tools that only till to 4 inches will not sufficiently manage compaction.3
  • Subsoilers with straight or bent-leg shanks can fracture compaction layer without much soil disturbance. Parabolic shanks do more surface disturbance and are not recommended because more secondary tillage will be needed prior to planting.
  • Fall tillage may not be possible this fall if conditions stay wet and deep tillage will have to be delayed until spring.

Sources: 1Stahl, L. 2014. Storing, drying, and handling wet soybeans. University of Minnesota Crop News. 2Stanton, M. 2017. Recommendations for repairing harvest ruts prior to planting without causing further soil compaction. Michigan State University. 3Duiker, S. 2015. Soil compaction management at harvest time. Ohio State University C.O.R.N. newsletter. 171019100454