No-Till and Reduced Tillage

Definition

Minimizing the intensity (frequency and aggressiveness) of soil-disturbing activities related to residue management, seedbed preparation, nutrient management, planting and pest control while planting and growing crops.

Purpose

Reduce erosion and transport of adsorbed particulate phosphorus (P)
Improve soil health and build resilience for climate-smart agricultural production
Conserve soil moisture for crop use and increased yield
Reduce particulate emission to the atmosphere

How Does This Practice Work?

Leaving crop residue on the soil surface year around, before and after planting, provides soil surface protection at critical times to protect the soil against wind and water erosion. Reducing tillage operations reduces tillage erosion, improves soil surface properties, including improved soil aggregation accounting for increased infiltration and percolation; less compaction due to less usage of field implements; and more biological activity due to an increase in organic matter. Adding soil surface cover increases water infiltration, reducing soil drying and maintains more moisture for crop utilization.

Where This Practice Applies and Its Limitations

This set of management practices applies to all cropland where tillage is commonly performed to loosen soil, prepare a seedbed, seed crops and control pests and unwanted vegetation. These tillage practices are effective control measures where soil erosion processes carry particulate phosphorus from the soil surface.

Although conservation tillage and crop residue management enhance soil surface properties, these practices may result in fertilizer and manure applications that are left on the soil surface. Surface application of fertilizer and manure leaves nutrients vulnerable to direct losses during runoff and also builds a stratified layer of crop nutrients (including phosphorus) on or near the soil surface. In both cases, the soil surface is vulnerable to rainfall, runoff, and wind events that can remove this highly concentrated material from the soil surface. Therefore, subsurface placement of manure or fertilizer is recommended whenever possible. While reduced tillage and soil organic matter buildup contribute to stable soil structure deep into the soil profile, this undisturbed structure produces macropores and preferential flow channels that can direct nutrients (including phosphorus) downward into deeper parts of the soil profile. This movement of P can result in substantial losses of P to surface water where subsurface drainage systems (i.e., tile drainage) are used.

Effectiveness

Conservation tillage and crop residue management are very effective at reducing soil erosion. Crop, climate and soil conditions impact the efficiency and effectiveness of this set of management practices. Nevertheless, no-till and reduced tillage are highly successful for controlling erosion. The use of current erosion prediction models (RUSLE2 for water and WEQ for wind) will provide a site-specific estimate of soil erosion losses or reductions.

Absence of soil disturbance and build up of soil organic matter will improve water and nutrient infiltration with time. Residue mulch and reduced soil surface disturbance can conserve up to 30 percent more soil water for crop uptake, and, therefore, increase crop nutrient utilization during critical periods of crop production.

Cost of Implementing the Practice

Conservation tillage and crop residue management will reduce the number of unnecessary tillage passes and machinery expenses. Each tillage pass would bury additional crop residue. Tillage operations require operator time, fuel and depreciation of equipment, all of which have a cost to the producer. The initial cost of equipment changeover and increased management required by the producer/operator will be offset by eventual savings in time, fuel and equipment depreciation.

Operation and Maintenance

Several years of tillage reduction and increased crop residue management are required before the full benefits of these practices can be realized. Less tillage and greater amounts of crop residue on the soil surface provide the greatest protection from both soil erosion and runoff losses of nutrients in particulate forms. Existing soil compaction, as well as perennial weed control, must be addressed early in the tillage modification. Perennial weeds and other pests can be controlled by rotating crops (including cover crops) and mode of pesticide action.

References

Residue and Tillage Management, No Till (Code 329) NRCS Conservation Practice Standard. September 2016. https://www.nrcs.usda.gov/resources/guides-and-instructions/residue-and-tillage-management-no-till-ac-329-conservation

Residue and Tillage Management, Reduced Till (Code 345) NRCS Conservation Practice Standard. September 2016. https://www.nrcs.usda.gov/resources/guides-and-instructions/residue-and-tillage-management-reduced-till-ac-345-conservation

Nutrient Management (Code 590) NRCS Conservation Practice Standard. May 2019. https://www.nrcs.usda.gov/resources/guides-and-instructions/nutrient-management-ac-590-conservation-practice-standard.

For Further Information

Contact your local soil and water conservation district, USDA-NRCS or Cooperative Extension Service office. Cost-share assistance may be available. To find your local USDA Service Center, visit https://www.nrcs.usda.gov/contact/find-a-service-center.

Current Authors

Nutifafa Adotey
University of Tennessee
nadotey@utk.edu

Don Flaten
University of Manitoba
don.flaten@umanitoba.ca

Previous Authors

Jerry Lemunyon and Chris Gross,

USDA-NRCS

Editing and Design

Deanna Osmond
NC State University

Forbes Walker
University of Tennessee

Citation:

Adotey, N. and D. Flaten. 2023. No-till and Reduced Tillage. SERA17 Phosphorus Conservation Practices Fact Sheets. https://sera17.wordpress.ncsu.edu/no-till-and-reduced-tillage/