Fall Tillage Considerations

As combines roll to a stop after fall harvesting, agricultural operations must pivot to soil preparation activities. The decisions made during this time can have a direct impact on efficiency, soil health, and profit potential for the next growing season. This information explores the strategic considerations of fall tillage that can help farmers optimize their operations while helping to preserve soil integrity.

Understanding Tillage: The Basics

Q: What is tillage?

A: Tillage refers to the agricultural practice of mechanically moving soil in a matter to help create a suitable seedbed, control weeds, reduce compaction, manage residue, and to incorporate organic matter or nutrients. However, it’s essential to understand the implications of tillage on soil health.

Q: Why tillage may be unfavorable?

A: While tillage is a valuable tool, excessive tillage can disrupt soil structure, reduce surface organic matter, disturb soil microorganisms and worms, release carbon to the atmosphere, and can allow for water and wind erosion.

Q: Is tillage the same as moldboard plowing?

A: Tillage is a broad term that encompasses various soil preparation methods such as harrowing, chiseling, disking, deep ripping, and moldboard plowing. Moldboard plowing is a specific tillage operation that inverts the soil to help bury crop residue, incorporate fertilizer nutrients, control weed growth, and remove compaction layers.

Q: What is fall tillage?

A: Fall tillage is the process of disturbing the soil after harvest to help incorporate fertilizer, break up and incorporate crop residue, reduce compaction, manage weed growth, and prepare the soil for spring activity.

Q: Should fall tillage be a consideration?

A: Fall tillage can be beneficial to help reduce heavy residue and compaction, manage weed growth, and incorporate fertility. However, tillage can increase the potential for water and wind erosion if the soil is left bare.

Q. What is the focus of fall vs spring tillage?

A. Fall tillage focuses on residue management, nutrient incorporation, reducing compaction, and weed control. Spring tillage focuses on seedbed preparation with equipment that crumbles soil aggregates, weed control, and nutrient incorporation such as urea.

Q. Is fall or spring tillage better?

A. For heavy soils, fall tillage may allow more time for the soil to fracture into small aggregates and for residue to deteriorate. Aggressive spring tillage, particularly when soils are wet, may result in chunky clods that are hard to fracture into a desired seedbed. Spring tillage can reduce the time the soil is exposed to potential erosion.

Q. What is winter tillage?

A. This refers to minimal soil preparation during winter periods, often for weed control, manure applications, or late seeding in warmer climates.

Q. What is summer tillage?

A. Summer tillage may be used to manage weeds in fallow fields or to prepare for fall crops.

Q. What are the Four Major Minimum Tillage Practices?

A.

1. No-till: There is no tillage and seeds are directly into the soil with minimal soil disturbance.
2. Strip-till: Nutrients and seeds are deposited into a narrow-tilled strip during the planting operation.
3. Ridge-till: Permanent ridges are created for seed rows. Ridge surface is scraped of residue and deposited between the rows during the planting process.
4. Mulch-till: Soil is left rough and cloddy by using chisel plows, field cultivators, disks, sweeps, or blades till the soil before planting; however, the soil is not inverted. About 30% or more of crop residue is left on the soil surface to help deter erosion.

Q. What is the advantage of minimum tillage?

A. Minimum tillage helps reduce erosion, maintain surface organic matter, sustain microorganisms and worms that are important for reduction of soil organic matter, nutrient availability, and reduction of surface water, respectively.

Q. What is the most favorable tillage system to minimize soil loss?

A. No-till is regarded as the most effective for minimizing soil loss.

Q. Are there fall-planted crops?

A. Cover crops may be seeded into a standing crop prior to harvest or planted after harvest to help protect the soil from erosion, improve organic matter, utilize nutrients that may be lost via leaching or runoff, and weed suppression. Winter wheat may be planted following another crop.

Q. How does tillage manage weeds?

A. Aggressive tillage can bury weed seeds too deep for germination and help disrupt growth cycles.

Q. Is it better to till before or after a rain?

A. Tilling wet soil can cause compaction, and result in hard soil chunks. Tillage on overly dry soil often results in the movement of dust. Aim for moist soil that crumbles easily.

Q. What is the depth of shallow plowing?

A. Shallow plowing is generally in the 4 to 6-inch range.

Understanding the nuances of fall tillage and related practices is a key for helping to optimize soil health and yield potential. By understanding the benefits and drawbacks of tillage, farmers can make informed decisions that help to enhance productivity and sustainability. Whether choosing between fall or spring tillage or deciding on the best crops to plant, strategic planning helps lead to successful harvests and long-term soil vitality.

Sources
Janssen, C. and Hill, P. 1994. What is conservation tillage? CT-1. Conservation Tillage Service. Cooperative Extension Service. Purdue University. https://www.extension.purdue.edu/extmedia/CT/CT-1.html

Residue and tillage management, reduced till. Code 345. 345-CPS-1. Conservation Practice Standard. 2016. Natural Resources Conservation Service. United States Department of Agriculture (USDA). https://www.nrcs.usda.gov/sites/default/files/2022-09/Residue_And_Tillage_Management_Reduced_Till_345_CPS.pdf

Veseth, R., Karow, R. 1999. Direct seeding or no-till…. What’s the difference? Pacific Northwest Conservation Tillage Handbook Series No. 23. Chapter 2 – Conservation Tillage Systems and Equipment, May 1999. Pacific Northwest STEEP (Solutions to Environmental and Economic Problems). Washington State University. https://pnwsteep.wsu.edu/pnw-conservation-tillage-handbook/direct-seeding-or-no-till-whats-the-difference/

Corn tillage systems. 2014. Corn Agronomy. University of Wisconsin. https://corn.agronomy.wisc.edu/management/l007.aspx

1017_631701