United States Department of Agriculture

Tillage Intensity and Conservation 

Cropping in the United States

Roger Claassen

Maria Bowman

Jonathan McFadden

David Smith

Steven Wallander

Economic

Research

Service

Economic

Information

Bulletin

Number 197

September 2018
Economic Research Service 

www.ers.usda.gov

United States Department of Agriculture

Recommended citation format for this publication:

Claassen, Roger, Maria Bowman, Jonathan McFadden, David Smith, Steven Wallander. 

Tillage Intensity and Conservation Cropping in the United States, EIB-197, U.S. 

Department of Agriculture, Economic Research Service, September 2018.

Cover image: USDA/NRCS.

Use of commercial and trade names does not imply approval or constitute endorsement by USDA.

To ensure the quality of its research reports and satisfy governmentwide standards, ERS requires that all research 

reports with substantively new material be reviewed by qualified technical research peers. This technical peer 

review process, coordinated by ERS' Peer Review Coordinating Council, allows experts who possess the technical 

background, perspective, and expertise to provide an objective and meaningful assessment of the output’s substantive 

content and clarity of communication during the publication’s review.

In accordance with Federal civil rights law and U.S. Department of Agriculture (USDA) civil rights regulations and 

policies, the USDA, its Agencies, offices, and employees, and institutions participating in or administering USDA 

programs are prohibited from discriminating based on race, color, national origin, religion, sex, gender identity 

(including gender expression), sexual orientation, disability, age, marital status, family/parental status, income derived 

from a public assistance program, political beliefs, or reprisal or retaliation for prior civil rights activity, in any program or 

activity conducted or funded by USDA (not all bases apply to all programs). Remedies and complaint filing deadlines 

vary by program or incident.

Persons with disabilities who require alternative means of communication for program information (e.g., Braille, large 

print, audiotape, American Sign Language, etc.) should contact the responsible Agency or USDA's TARGET Center at 

(202) 720-2600 (voice and TTY) or contact USDA through the Federal Relay Service at (800) 877-8339. Additionally, 

program information may be made available in languages other than English.

To file a program discrimination complaint, complete the USDA Program Discrimination Complaint Form, AD-3027, 

found online at How to File a Program Discrimination Complaint and at any USDA office or write a letter addressed to 

USDA and provide in the letter all of the information requested in the form. To request a copy of the complaint form, call 

(866) 632-9992. Submit your completed form or letter to USDA by: (1) mail: U.S. Department of Agriculture, Office of 

the Assistant Secretary for Civil Rights, 1400 Independence Avenue, SW, Washington, D.C. 20250-9410; (2) fax: (202) 

690-7442; or (3) email: program.intake@usda.gov.

USDA is an equal opportunity provider, employer, and lender.
United States Department of Agriculture

Economic

Research

Service

Economic

Information

Bulletin

Number 197

September 2018

Abstract

Reducing tillage and increasing soil cover can enhance soil health. Conservation tillage, 

particularly no-till or strip-till, used in conjunction with soil cover practices (like 

conservation crop rotations and cover crops) can lead to a range of soil health benefits: 

improved agricultural productivity, greater drought resilience, and better environmental 

outcomes. This report uses field-level data to estimate tillage practice adoption based on 

soil disturbance as measured by absence of tillage operations (for no-till) and the Soil 

Tillage Intensity Rating (STIR, for mulch till). To gauge the intensity of tillage over 

time, we estimate the number of years no-till or strip-till are used over a 4-year period. 

Rates of adoption for practices that affect soil cover—including conservation crop rotations, cover crops, double cropping, fallowing, and residue harvest or grazing—are also 

estimated. The rates at which these practices are adopted in conjunction with no-till/

strip-till are also estimated to illustrate interactions between tillage and practices that 

affect soil cover.

Keywords: tillage, no-till, mulch-till, conservation tillage, conservation crop rotation, 

cover crop, double cropping

Acknowledgments

The authors would like to thank the following for technical peer reviews: Lyubov 

Kurkalova, North Carolina A&T State University; Adam Reimer, Kellogg Biological 

Station, Michigan State University; Seth Wechsler, USDA, Economic Research Service; 

Mark Xu, USDA, Natural Resources Conservation Service; and Kathryn Zook, USDA, 

Office of the Chief Economist. We also thank Dale Simms and Cynthia A. Ray, USDA/

ERS, for editorial and design services.

Tillage Intensity and Conservation 

Cropping in the United States

Roger Claassen, Maria Bowman, Jonathan McFadden, 

David Smith, and Steven Wallander
ii

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

Tillage Practices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

Cropping Practices That Improve Soil Health . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

How Tillage Estimates Differ Using STIR and Residue Methods . . . . . . . . . . . . . . . . . . . . . . .15

Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19

Contents

Errata 

On October 12, 2018, the report Tillage Intensity and Conservation Cropping in the United 

States was reposted to correct for coding errors that resulted in the miscalculation of some 

estimates for conservation cropping, cover crops, and other practices that affect crop residue. 

Specifically, Figure 3, Figure 4, Table 1a, and Table 1b have been replaced. Conforming changes 

have been made in the text on pages 6, 9, 10, 11, 12, and 18. The largest changes are an increase 

in cover crop acreage for corn (2016) and cotton (2015) and an increase in conservation cropping 

for wheat (2017). Acreages for tillage types in Tables 1a and 1b are lower because observations 

with less than 4 years of crop and tillage data were inadvertently included (but have now been 

excluded). All changes are restricted to figures, tables, and text that rely on ARMS cropping and 

tillage history data. 
ERS is a primary source 

of economic research and 

analysis from the U.S. 

Department of Agriculture, 

providing timely information on economic and policy 

issues related to agriculture, 

food, the environment, and 

rural America.

United States Department of Agriculture

A report summary from the Economic Research Service September 2018

Tillage Intensity and Conservation 

Cropping in the United States

Roger Claassen, Maria Bowman, Jonathan McFadden, 

David Smith, and Steven Wallander

What Is the Issue? 

Tillage is used to control weeds, incorporate crop residue, and prepare land for planting, but 

minimizing soil disturbance and maintaining soil cover are critical to improving soil health. 

Crop choice is typically driven by crop prices, soils, and climate, but crop rotations can also 

break weed and pest cycles, improve crop yields, and reduce soil erosion. USDA conservation 

programs are increasingly focused on reducing tillage and promoting cropping practices (like 

cover crops and crop rotations) that could improve soil health. Progress toward improving soil 

health and soil erosion control can be monitored, at least in part, by tracking trends in the use 

of practices that reduce or minimize soil disturbance and increase soil cover. 

What Did the Study Find?

Conservation tillage practices—including no-till, strip-till, and mulch-till—vary widely across 

crops and regions: 

•	 Conservation tillage was used on roughly 70 percent of soybean (2012), 65 percent of 

corn (2016), 67 percent of wheat (2017), and 40 percent of cotton (2015) acres. 

•	 The share of total conservation tillage that is no-till also varied from 67 percent (45 

percent of total acreage) in wheat (2017) and 56 percent (40 percent of total acreage) 

in soybeans (2012) to 44 percent (18 percent of total acreage) in cotton (2015) and 42 

percent (27 percent of total acreage) in corn (2016). 

•	 Despite initial increases in no-till wheat (2004-09) and soybeans (2002-06), more recent 

data show less rapid gains for wheat (2009-17) and an apparent decline in no-till adoption 

on soybeans (2006-12).

•	 For individual crops, the rate of no-till varies by region. The likelihood of no-till corn, for 

example, is relatively high in the Northern Great Plains (50 percent of conservation tillage 

in corn, 34 percent of total corn acreage), Prairie Gateway (69 percent of conservation 

tillage, 49 percent of corn), and the South (the Eastern Uplands, Southern Seaboard, and 

Mississippi Portal combined) (67 percent of conservation tillage, 53 percent of corn).

•	 Almost 50 percent of corn, soybean, wheat, and cotton acreage was in no-till or strip-till 

at some time over a 4-year period (including the survey and 3 previous years), but only 

about 20 percent of these acres were in no-till or strip-till all 4 years. 

www.ers.usda.gov

 

Tillage Intensity and Conservation 

Cropping in the United States

 

Summary
Trends in conservation tillage adoption

 

Note: Mulch till is land with tillage and a Soil Tillage Intensity Rating less than 80.

Source: USDA Economic Research Service, based on USDA Agricultural Resource Management Survey (ARMS) data for 2002-2017. 

Residue and cover practices can also affect soil health by determining—in conjunction with tillage practices—the extent to which soil remains covered throughout the year. Adoption of these practices varies across 

crops and, to some extent, across tillage practices: 

•	 Conservation crop rotations (rotations that include high-residue crops that require relatively little 

nitrogen) are more frequently identified on land in the survey of corn producers (2016) than in the 

soybean, wheat, or cotton surveys. 

•	 Double cropping and cover crops—which increase crop residue—were used on 12 percent or less of all 

surveyed fields. 

•	 Fallowing—which typically reduces crop residue—was used on 13 percent of wheat acreage and less 

than 5 percent of other crops. 

•	 Corn stover (residue) removal through grazing or harvest—which reduces residue—occurred on about 

16 percent of corn acres. 

•	 Evidence suggests that farms using no-till or strip-till practices, at least in some years, are more likely 

to also adopt residue- and cover-increasing practices. 

How Was the Study Conducted? 

All data are from the Agricultural Resource Management Survey (ARMS), a national-level survey of farming 

operations conducted by USDA’s National Agricultural Statistics Service (NASS) and ERS. Data are based on 

the three most recent field-level, crop-specific production practice surveys of the four most widely grown U.S. 

crops: corn (2005, 2010, and 2016); soybeans (2002, 2006, and 2012); cotton (2003, 2007, and 2015); and 

wheat (2004, 2009, and 2017). Data on tillage operations, supplied by survey respondents, are used to identify 

fields in no-till (absence of tillage operations) and mulch till (tillage operations with a Soil Tillage Intensity 

Rating (STIR) less than 80). Using the STIR—rather than methods based on soil residue cover (previously 

used by ERS to estimate conservation tillage adoption)—focuses our estimates on soil disturbance, rather 

than a combination of soil disturbance and residue from the previous crop. To capture the interaction of tillage 

and practices that increase soil cover, we estimate the extent to which conservation crop rotations, cover 

crops, double cropping, and fallow are used in conjunction with no-till. ARMS data provide a 4-year history 

of crops grown (including cover crops) and an indicator of no-till or strip-till for each crop in the history, as 

identified by the survey respondent. 

www.ers.usda.gov
1

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

Tillage Intensity and Conservation 

Cropping in the United States

Introduction

Farmers till for many reasons. Tillage is used to prepare the soil for planting, control weeds, incorporate manure or fertilizer spread on the soil surface, and mix crop residue into the soil. Soils 

exposed by tillage typically absorb more heat and warm up more quickly, allowing earlier planting 

for some crops (particularly corn) in regions where spring weather is often cool and wet. 

Conservation tillage—the use of tillage methods that disturb the soil less than “conventional” 

tillage—was originally promoted as a soil and water conservation technology. In the aftermath of 

the Dust Bowl, early conservation tillage implements—such as the Hoeme, Noble, and stubblemulch plows—were developed to keep crop residue on the soil surface, reducing soil erosion and 

conserving soil moisture (Allen and Fenster, 1986; Russel, 1976; Unger and Baumhardt, 2001). 

Because soil and water conservation were the primary purposes and residue cover is effective for 

both, conservation tillage was initially defined as any system that retained at least 30 percent residue 

cover at planting (Conservation Tillage Information Center, 2018). 

In recent decades, farmers have increasingly adopted conservation tillage methods for a broader set 

of reasons. In addition to reducing erosion and preserving soil moisture, conservation tillage can 

reduce crop production costs by reducing the use of fuel, labor, and tillage machinery. Herbicidetolerant crops have increased the availability of pesticides for post-emergent weed control and 

further reduced reliance on tillage (Givens et al., 2009; Perry et al., 2016). Increasingly sophisticated 

planters equipped to cut through or clear crop residue from the row have made it easier to plant 

directly into untilled, residue-covered soil. 

More recently, USDA’s Natural Resources Conservation Service (NRCS) has identified soil health as 

a key focus for soil management (USDA-NRCS, 2018a). Soil health refers to the “continued capacity 

of soil to function as a vital living ecosystem that sustains plants, animals, and humans” (USDANRCS, 2018a). Healthier soils1 can reduce environmental damage and benefit farmers. For example, 

the adoption of soil health practices can improve rainfall infiltration rates and soil water-holding 

capacity, reducing environmental damage due to sediment, nutrient, and pesticide runoff while 

reducing the risk of low crop yields by increasing drought resilience (Karlen et al., 1994; MoebiusClune et al., 2008; Rawls et al., 2003). 

1Although there are many physical, chemical, and biological indicators of soil health, soil scientists have developed 

several indicators that reflect underlying processes and help us assess the health of soils. These include soil organic carbon, 

soil aggregation, readily available carbon and nitrogen pools, and measures of the activity and diversity of the soil microbial 

community (USDA-NRCS, 2018b).
2

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

USDA’s NRCS outlines four basic principles to help farmers manage for soil health by protecting 

and “feeding” the soil2 (USDA-NRCS, 2017; Moore-Kucera, 2018):

•	 Keep the soil covered (protect),

•	 Reduce soil disturbance (protect),

•	 Keep living roots in the soil (feed), and 

•	 Diversify using rotations and cover crops (feed).

Conservation tillage, which protects the soil by reducing soil disturbance and keeping the soil 

covered, is considered to be a key component of a soil health management system (USDA-NRCS, 

2017). Other management practices that increase soil cover, crop residue, or crop diversity may also 

contribute to building soil health. Conservation crop rotations and cover crops, for example, increase 

the amount of residue available for soil cover, the diversity of plants grown, and the proportion of the 

year when living roots are in the soil. 

Given increasing focus on soil health, our characterization of tillage practices focuses on (1) the 

intensity of soil disturbance, (2) consistency in use of minimum-disturbance tillage practices over 

time in individual fields, and (3) the relationship of tillage intensity to practices that increase residue, 

crop diversity, and crop cover. To focus on soil disturbance, the absence of tillage is used to define 

no-till systems and the Soil Tillage Intensity Rating (STIR) is used to define how much tillage is 

allowed in any conservation tillage system. The term “conservation tillage” generally encompasses 

no-till and mulch-till (any tillage practice that is not no-till and has a STIR rating of less than 80). 

Strip-till is a mulch-till method used in row crops to minimize soil disturbance by tilling only in 

narrow strips over the rows. Uptake of tillage practices is estimated using USDA’s Agricultural 

Resource Management Survey (ARMS) data for corn (2005, 2010, 2016), cotton (2003, 2007, 

2015), soybeans (2002, 2006, 2012), and wheat (2004, 2009, 2017) (see box, “USDA’s Agricultural 

Resource Management Survey”). 

2Feeding the soil means providing an environment where a diverse set of soil microbes can thrive. These microbes provide 

nutrients (and other compounds) to the plant at the root-soil interface where the plants can take them up. Microbial food is 

exuded by plant roots. Sugars from living plant roots, recently dead plant roots, crop residues, and soil organic matter all feed 

the many and varied members of the soil food web. A diverse set of soil microbes requires planting a diverse set of crops.
3

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

USDA’s Agricultural Resource Management Survey

USDA collects information on farm costs and returns, farm financial conditions, farm structure, and crop/

livestock production practices using the Agricultural Resource Management Survey. Data underlying this study 

are from the field-level (phase II) survey. The questionnaire collects information on crop production inputs, 

management practices, and costs (fertilizer, pesticide, labor, tillage, seed, etc.) for target commodities, including 

corn, soybeans, wheat, cotton, sorghum, barley, oats, rice, and peanuts. ARMS data include extensive field-level 

information on cropping patterns, including double cropping and cover crops (some surveys), field operations 

(used to estimate tillage practices), residue management, nutrient applications (including manure), and many 

other practices. Data are collected on a rotating basis for each crop; the interval between surveys depends on 

the importance of the crop (as measured by acreage or production value) and the rate at which crop-specific 

production technologies are changing. These rotations do not have a fixed length and can change in response 

to a number of concerns. For example, data on corn production were collected in 2005, 2010, and 2016. Wheat 

data were collected in 2004, 2009, and 2017. For more information on how ARMS data are collected, please see 

USDA, ERS, 2018. 

Glossary

Conservation tillage—Tillage management practices that result in a STIR (see below) of less than or equal to 

80, and do not use a moldboard plow. Conservation tillage practices can include mulch-till, no-till, or strip-till.

Conservation crop rotation—A sequence of crops on the same field for the purpose of supporting soil health, 

conserving natural resources, and improving environmental outcomes from farming (USDA-NRCS, 2014a). 

Specifically, we define a conservation rotation to include at least one high-residue crop (e.g., corn), at least one 

low-nitrogen crop (e.g., grass or legume), and as attaining a threshold level of average annual residue. A cornsoybean (only) rotation is not considered a conservation crop rotation.

Conventional tillage—A combination of tillage management practices that result in a STIR of greater than 80. 

Cover cropping—Planting a crop for seasonal cover, as when annual ryegrass is planted during the winter 

months between cash crops. 

Crop residue—Plant material from a crop, such as cornstalks or soybean stubble, that remains after harvest. 

Residue can be left on the field, grazed, or harvested.

Double cropping—Harvesting two commodity crops from the same field in a given year (e.g., winter wheat and 

soybeans).

Fallowing—Leaving land idle for a year, often to accumulate moisture in semi-arid regions. Fallowing is most 

often used in wheat production.

Mulch-till—A type of conservation tillage where soil is tilled (for example with a chisel or disk) but soil disturbance is low (STIR less than 80). 

No-till—The practice of refraining from tilling the soil from harvest of the previous crop to harvest of the 

current crop. 

Residue grazing—The practice of letting livestock graze crop residue after a crop has been harvested.

Residue harvest—The practice of harvesting the residue of a cash crop for a secondary use, such as harvesting 

corn residue for animal feed or bedding material.

Soil Tillage Intensity Rating (STIR)—A numerical index that represents the type and severity of disturbance 

caused by tillage operations. The STIR value incorporates the type, speed, depth, and degree of disturbance 

caused by tillage management decisions. The STIR is the sum of STIR values of individual field operations.

Strip-till—A tillage system used to minimize soil disturbance in row crops by tilling only in narrow strips 

where seeds are planted. In fields where tillage is limited to narrow strips, the STIR is typically well under 80.
4

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

Tillage Practices

While conventional tillage, conservation tillage, and no-till are often presented as a simple choice, 

the choice of tillage practice actually consists of a wide set of choices. Many different types of 

tillage equipment—plows, discs, etc.—can be used for tillage operations. Prior to planting, farmers 

may make zero, one, or multiple passes with the tillage equipment. Tillage practices are much 

researched because they affect both crop residue and soil disturbance. Other field operations during 

crop production (e.g., planting and fertilizer application) also impact residue and soil disturbance. 

We define no-till as the absence of tillage operations from harvest of the previous crop to harvest of 

the current crop. Mulch till involves limited tillage operations. National practice standards for mulch 

(reduced) tillage,3 established by USDA’s Natural Resources Conservation Service (NRCS), set a 

maximum STIR of 80 for “Residue and Tillage Management, Reduced Till” (USDA-NRCS, 2016). 

Conservation tillage was used on a majority of wheat (67 percent in 2017), corn (65 percent, 2016), 

and soybeans (70 percent, 2012) in the most recent surveys (fig. 1a). Conservation tillage was used 

on just 40 percent of cotton acres (2015). No-till accounted for more than 50 percent of conservation tillage acres on 2017 wheat (67 percent of conservation tillage; 45 percent overall) and 2012 

soybeans (56 percent; 40 percent overall). Smaller proportions of conservation tillage were no-till on 

2016 corn (42 percent; 27 percent overall) and 2015 cotton (44 percent; 18 percent overall). 

In general, no-till adoption increased from 2000 to 2007 (Horowitz et al., 2010). Our data (2002-

17; fig. 1b) include periods of increasing no-till adoption, particularly for wheat (2004-2009) 

and soybeans (2002-2006), and periods when no-till adoption leveled off and may have actually 

declined, particularly for soybeans (2006-2012) and cotton (2007-2015). Changes in no-till are far 

less dramatic for corn, where the data indicate only modest gains for 2005-10 and 2010-16. 

The Soil Tillage Intensity Rating (STIR) is a measure of soil disturbance developed by NRCS to 

reflect all field operations. A STIR value is assigned to each field operation. The type of tillage 

equipment, tillage depth, speed, and percent of soil surface disturbed (width) are all factors that 

help determine operation-specific STIR values (USDA-NRCS, 2008). The STIR for the field 

is the simple sum of STIR values for all field operations from the harvest of the previous crop 

through the harvest of the current crop. The STIR is an index (without units) that typically falls 

in the range of 0-200, with high values associated with higher tillage intensity. 

3What we define as “mulch tillage” is similar to “reduced tillage” in the most recent NRCS practice standards (USDANRCS, 2016). We continue to use the term “mulch tillage” to differentiate this practice from “reduced till,” previously defined 

by the Conservation Tillage Information Center (CTIC) as land where residue cover is 15-30 percent after planting and is not 

considered to be conservation tillage. 
5

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

Figure 1a

Conservation tillage, 2002-2017

Percent of planted acres

0

10

20

30

40

50

60

70

80

90

2004 2009 2017 2005 2010 2016 2002 2006 2012 2003 2007 2015

Wheat Corn Soybeans Cotton

Mulch Till No-Till

Note: No-till is based on the absence of tillage operations reported in the Agricultural Resource Management Survey (ARMS). 

Mulch till is indicated when the Soil Tillage Intensity Rating (STIR) is less than or equal to 80 (for the entire season) with 

some tillage operations. 

Source: USDA Agricultural Resource Management Survey data for 2002-2017.

Figure 1b

No-till adoption, 2002-2017

Percent of planted acres

0

10

20

30

40

50

2000 2002 2004 2006 2008 2010 2012 2014 2016 2018

Wheat Corn Soybeans Cotton

Note: No-till is based on the absence of tillage operations reported in the Agricultural Resource Management Survey (ARMS). 

Source: USDA Agricultural Resource Management Survey data for 2002-2017.

Conservation tillage adoption also varies across regions (fig. 2). These variations may reflect a range 

of concerns, including soil moisture conservation, timely planting (tilled soils tend to warm more 

quickly than untilled soils), and the risk of soil erosion. In corn, no-till adoption is greater in drier 

regions (Northern Great Plains, Prairie Gateway) and warmer regions (Prairie Gateway, the South). 

Higher adoption in dryer regions may reflect the importance of conserving soil moisture in areas 

where rainfall is limited (Davey and Furtan, 2008; Ding et al., 2009). Higher adoption in warmer 

regions may mean that tillage is not needed to facilitate soil warming and ensure timely planting. 

No-till soybeans are most likely in warm regions (Prairie Gateway, the South) and seem to be more 
6

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

likely in portions of the north with higher rainfall (e.g., no-till is more likely in the Heartland and 

the Northern Crescent than in the Northern Great Plains). A higher rate of no-till adoption in regions 

with greater rainfall has been observed previously (Pautsch et al., 2001) and may reflect concern 

about soil erosion. Conservation tillage (including no-till) in wheat is most common in the Basin and 

Range, Northern Great Plains, Northern Crescent, and Heartland regions, exceeding 50 percent of 

2017 acreage in each of these regions. 

Tillage over time. Soil health benefits of conservation tillage may be fully realized only when practices minimize soil disturbance (e.g., no-till, strip-till) consistently over time (USDA-NRCS, 2014b). 

Nonetheless, many producers alternate no-till or strip-till with tillage practices that disturb the 

entire soil surface (conventional or mulch-till). The prevalence of no-till/strip-till in any given field 

may depend on the likelihood of these practices on the crops grown in rotation in the region where 

the field is located. Topography and soil conditions are also likely determinants. Previous research 

shows that “highly erodible” land and well-drained land (land that dries out quickly enough to avoid 

crop damage due to wet conditions) are more likely than other land to be continuously in no-till over 

time (Wade and Claassen, 2017).

In the ARMS data, tillage practice estimates are derived from two sources. For survey years (e.g., 

2005, 2010, and 2016 for corn), tillage practices are estimated from detailed data on field operations. 

For the 3 years prior to the survey year (e.g., 2013, 2014, and 2015 for the 2016 corn survey), ARMS 

respondents are asked to list up to two crops for each year (one fall-planted and one spring-planted 

crop) and whether no-till or strip-till4 was used to grow each listed crop.5 Using these data, each 

surveyed field was placed in one of three tillage categories: continuous no-till/strip-till (no full-width 

tillage during the 4-year period), alternating no-till/strip-till (full-width tillage in 1-3 years), and 

continuous tillage (full-width tillage in all 4 years). 

Using these data, an estimated 21 percent of the combined acreage in the four surveys (corn, 2016; 

cotton, 2015; soybeans, 2012; and wheat, 2017) were continuously in no-till or strip-till in all 4 years 

(fig. 3). Continuous no-till/strip-till was most common in those fields where the surveyed crop was 

wheat. Continuous no-till/strip-till was least common where the surveyed crop was cotton. 

On an estimated 30 percent of land in the four crop surveys combined, producers used some combination of no-till or strip-till and full-width tillage (alternating no-till/strip-till). An estimated 49 

percent of land across all four crops was continuous tillage (that disturbs the entire soil surface) in 

all 4 years. Continuous tillage was most common in the corn and cotton surveys.

4The 2012 soybean survey asks only about no-till. The 2015 cotton and 2016 corn surveys ask whether no-till or strip-till 

was used. Strip-till is not used in wheat.

5In the survey, no-till is defined as leaving soil and previous crop residue undisturbed from harvest to planting. Strip-till is 

defined as tilling a narrow strip over the row, leaving soil and previous crop residue between the rows undisturbed.
7

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

Figure 2

No-till and mulch-till adoption by crop and ERS farm resource region

0% 20% 40% 60% 80% 100%

Corn

Soybeans

Wheat

Corn

Soybeans

Wheat

Corn

Soybeans

Wheat

Corn

Cotton

Soybeans

Wheat

Corn

Cotton

Soybeans

Wheat

Wheat

Heartland

Northern Crescent

Northern Great Plains

Prairie Gateway

The South*

Fruitful Rim

Basin and Range

Mulch Till No Till Other

Farm Resource Region Tillage type

*‘The South’ includes Southern Seaboard, Mississippi Portal, and Eastern Uplands

0% 20% 40% 60% 80% 100%

0% 20% 40% 60% 80% 100%

0% 20% 40% 60% 80% 100%

0% 20% 40% 60% 80% 100%

0% 20% 40% 60% 80% 100%

0% 20% 40% 60% 80% 100%

Notes: No-till is based on the absence of tillage operations reported in the Agricultural Resource Management Survey 

(ARMS). Mulch till is indicated when the Soil Tillage Intensity Rating (STIR) is less than 80 (for the entire season). 

Source: USDA Agricultural Resource Management data for wheat (2017), corn (2016), soybeans (2012), and cotton (2015). 
8

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

Figure 3

Tillage over time, by surveyed crop and for all crops combined

Percent of planted acres

Continuous tillage Alternating no-till/strip-till Continuous no-till/strip-till

Corn, cotton, soybeans, 

and wheat combined 

0

10

20

30

40

50

60

70

Corn, 2016 Cotton, 2015 Soybeans, 2012 Wheat, 2017

49

30

21

Notes: Continuous tillage is continuous full-width tillage for 4 years. Surveyed fields grew wheat in 2017, soybeans in 2012, cotton in 2015, or corn in 2016, but could have been planted to other crops during any of the 3 years preceding the survey year. 

Source: USDA, Economic Research Service and USDA, National Agricultural Statistics Service, field-level data from the 

Agricultural Resource Management Survey, 2012, 2015, 2016, and 2017.
9

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

Cropping Practices That Improve Soil Health

Tillage decisions and their impacts on crop production cannot be fully understood in isolation. Many 

farmers make concurrent decisions about tillage, crops, residue-related practices, and other practices 

related to tillage (e.g., use of herbicide-tolerant seeds). These choices interact to determine an operation’s profitability because the production practices are often complementary. In other words, the 

incremental benefit from increased adoption of no-till or other conservation tillage practices depends 

on the crop or cropping practice. For example, no-till adoption is higher in some crops (wheat and 

soybeans) than others (corn and cotton). Field-level and farm-level evidence suggests that some 

farmers rotate tillage practices along with crops (Wade et al., 2015).

Conservation Crop Rotations . Crop rotations are common in U.S. agriculture. Conservation crop 

rotation refers to a sequence of crops on the same field for the purpose of supporting soil health, 

conserving natural resources, and improving environmental outcomes from farming (USDA-NRCS, 

2014a). There is no single definition of a conservation crop rotation. The crops grown vary based on 

crop prices, climate, growing conditions, resource concerns, and conservation/commodity policies. 

For example, rotating shallow-rooted with deep-rooted crops can help crops use more of the water 

available throughout various layers of soils. Including crops that provide food and habitat for beneficial insects (e.g., buckwheat or clover) or trap crops (that provide an alternate source of food) can 

reduce pest pressure. Excess nutrients applied to some crops can be partly taken up by a subsequent 

crop that roots quickly and at an appropriate depth (USDA-NRCS, 2014a). Our emphasis is on rotations with high-residue crops that can improve soil health when used in conjunction with conservation tillage, particularly no-till or strip-till. For this report, a conservation crop rotation6 must have: 

1. An average annual residue rating greater than 1.5 (see below), 

2. At least one high-residue crop (annual residue rating of at least 2), 

3. More than one crop in the rotation (including cover crops), and 

4. At least one low-nitrogen crop (e.g., a grass or legume). 

We assign annual residue ratings (obtained from USDA’s Natural Resources Conservation Service), 

which range from 0.25 to 4.0, for each crop. Very-high-residue perennial crops (e.g., alfalfa and 

other grasses) have a residue rating of 4. High-residue annual crops (e.g., corn, wheat, sorghum, 

and barley) have a residue rating of 2. Low-residue annual crops (e.g., soybeans and cotton) have 

a residue rating of 1. Based on this definition, a simple corn-soybean rotation is not considered 

a conservation crop rotation because its average annual residue rating is exactly 1.5. However, a 

soybean-winter wheat-corn rotation is considered a conservation crop rotation since it satisfies 

criteria (2) through (4) and has an average annual residue rating of 1.67 over the 3-year rotation.

Roughly 28 percent of 2016 corn acreage was planted as part of a conservation crop rotation, a larger 

share than for cotton (8 percent), soybeans (12 percent), and wheat (19 percent) in recent years (table 

1a). The predominance of conservation cropping varies by crop and tillage practice (fig. 4).

6This is designed to be consistent with characterizations of conservation crop rotations used in the Conservation Effects 

Assessment Project carried out by USDA\NRCS (Norfleet, 2018).
10

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

Figure 4

Share of planted acres adopting conservation crop rotation by crop and tillage practice

 

Note: Continuous tillage refers to continuous (4 years) full-width tillage. Error bars show 95 percent confidence interval for 

each estimate.

Source: USDA, Economic Research Service based on Agricultural Resource Management Phase II data for 2012, 2015, 

2016, and 2017. 

Multi-Cropping and Fallowing. The relative benefits of conservation crop rotations—and crop rotations more generally—can depend directly on the intensity of cropping. Rotations that involve more 

intensive use of cropland, including double cropping and cover cropping, increase residue production. In contrast, idled cropland—including fallowed fields—reduces residue production but is often 

used to accumulate moisture needed for crop production in drier climates.

Double cropping is the practice of harvesting two crops in 1 year. Cover cropping often involves 

planting two crops in 1 year but harvesting only one crop, although cover crops may be grazed or 

harvested for silage but not grain or seed (USDA-NRCS, 2014c).7 Both practices are uncommon 

(table 1a). Between 3 and 6 percent of corn, cotton, soybean, and wheat acres were double cropped 

in recent years. Similarly, 5 percent of 2016 corn acreage, 12 percent of 2015 cotton acreage, and 2 

percent of 2017 wheat acreage was cover cropped. Some highly productive cropland does not have 

sufficiently long growing seasons to accommodate two crops in the same year without reducing 

the economic returns to one or both crops (Borchers et al., 2014). Double cropping is highest in 

Southern States with longer growing seasons (Wade et al., 2015). Corn and soybeans are the most 

common spring-planted crops in these rotations, while winter wheat and rye are the most common 

fall-planted crops (Borchers et al., 2014). 

Differences in management of the fall-planted crop create differences in soil health benefits from 

cover cropping relative to double cropping (Bergtold et al., 2017). Although harvested crops leave 

residue on the field, unharvested cover crops can leave behind more. In cotton (2015) and corn 

(2016), cover crops are more likely to be grown in fields where no-till or strip-till is used continuously or at least in some years during the 4-year crop history, although these practices are applied 

jointly on only a small number of acres. Legume cover crops like hairy vetch, sunn hemp, and 

7ARMS respondents self-identify cover crops in the crop history table. 
11

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

winter peas can provide supplemental nitrogen to cash crops for the following season (Bergtold 

et al., 2017). Both double cropping and cover cropping increase crop residue available for cover, 

reducing soil erosion and the potential for leaching or runoff of agricultural chemicals. 

Fallowing is the practice of leaving a field unplanted for one or more seasons following crop harvest. 

This most commonly occurs as cultivated summer fallow—cropland left unplanted in dry environments to accumulate moisture before planting, typically to small grains. In 2017, 13 percent of 

wheat acreage was fallowed (table 1b). Fallowed cropland has been declining in recent decades 

(USDA-ERS, 2017) as acreages under intensified cropping practices have increased. Cropping 

patterns that simultaneously reduce fallowing and tillage intensity can increase soil organic matter, 

water content, and soil microbial activity and can improve overall soil structure (Nielsen and 

Calderón, 2011).

Other Cropping Practices That Influence Soil Health . Applying manure to cropland and 

harvesting or grazing of crop residues also influence soil structure and soil organic matter. In 

particular, the harvesting of residue reduces cover, increasing the potential for soil erosion, reducing 

organic matter formation, and (possibly) increasing nutrient requirements for the next crop (Karlen 

et al., 2014). In contrast, manure applications can significantly increase organic matter (Haynes and 

Naidu, 1998). 

Residue was grazed on 12 percent and harvested on 4 percent of 2016 corn acres (table 1b).8 In the 

western Corn Belt, corn stover has long been grazed or harvested for cattle feed. More recently, corn 

stover has been harvested for energy feedstock used in cellulosic biofuels plants in the central Corn 

Belt (Rosburg et al., 2017). Wheat has been grazed for cattle feed in seasons when early crop growth 

is sufficient to withstand temporary grazing without damaging grain yields. In 2017, 19 percent of 

wheat acreage was grazed. Wheat straw, which is often used as livestock bedding, was harvested 

from about 5 percent of wheat acres. Soybeans and cotton are low-residue field crops not typically 

used for grazing or residue harvest, so ARMS Phase II questionnaires do not elicit such information 

from soybean and cotton farmers. 

Manure directly increases soil organic matter since it is organic matter in the form of liquid, semidry, or solid waste. Manure’s contribution to soil organic matter varies directly with its carbonnitrogen ratio, which is affected by animal source and diet, as well as the duration and type of 

storage. All of these factors are highly variable, though recurring manure applications over many 

years clearly increase organic carbon, soil microbial activity, and porosity (Haynes and Naidu, 

1998).9 However, manure use varies significantly by crop. Nearly 16 percent of 2016 corn acreage 

received manure (table 1b) while only 4 percent of cotton (2105), 3 percent of soybeans (2012), and 

2 percent of wheat (2017) received manure. 

Linking Tillage, Cropping, and Residue Practices . There is some evidence to suggest that 

residue-increasing practices are more common on land in continuous no-till/strip-till or alternating 

no-till/strip-till, particularly for soybeans, wheat, and cotton (table 1a). Overall adoption of conservation rotations are higher for corn, but adoption rates for land in no-till/strip till (alternating or 

continuous) are not significantly different from the rate on continuously tilled corn acres. Between 

5 and 13 percent of cotton, soybean, and wheat acres in alternating no-till/strip-till were double 

8Across multiple ARMS survey years and target crops, farmers’ primary reason for not harvesting residue was either the 

desire to leave it for organic matter or because there was no market or other use. 

9It is difficult to precisely apply nutrients in manure, possibly leading to water quality issues. 
12

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

cropped. In contrast, only 2 to 4 percent of cotton, soybean, and wheat acres in continuous tillage 

were double cropped. This trend holds for cover crops, which are less common on cotton and corn 

acreage under continuous tillage.

The link between tillage and manure applications varies by crop. Just over 18 percent of continuously tilled corn acres received manure, while only 10 percent of continuously no-tilled/strip-tilled 

corn acres received manure (table 1a). Because corn is the primary feed grain grown in the United 

States, it is likely to be grown near large concentrations of livestock. (For cotton, manure applications may be more common on fields under no-till/strip-till practices. However, relatively wide confidence intervals around these estimates make it difficult to establish clear trends in manure use for 

cotton, soybeans, and wheat under various tillage systems.)

For cropping practices that reduce residue, there is less variability in acreage shares by tillage practices for each crop (table 1b). For example, the share of continuously tilled corn acres with residue 

harvested (4 percent) does not significantly differ from the share of corn acres in alternating no-till/

strip-till (4 percent) or continuous no-till/strip-till (2 percent). There are no clear relationships 

between tillage and fallowing for any of the major field crops. 
13

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

Table 1a

Conservation cropping and practices that increase residue by crop and continous tillage, 

alternating no-till/strip-till, and continuous no-till/strip-till

Crop Tillage Acres

Share of 

acres by 

crop

Conservation 

cropping

Double 

cropping Cover crop

Manure 

application

Share of planted acres by tillage category

(95% confidence interval)

Corn, 2016 Cont. till 44,058 0.55 0.26 0.02 0.03 0.18

95% CI ±2,388 ±0.042 ±0.005 ±0.009 ±0.026 

Alt. no/strip-till 21,747 0.27 0.33 0.05 0.05 0.14

95% CI ±2,596 ±0.062 ±0.016 ±0.016 ±0.050 

Cont. no/strip-till 14,203 0.18 0.29 0.01 0.08 0.10

95% CI ±1,734 ±0.066 ±0.006 ±0.027 ±0.051 

All tillage1 81,903 0.28 0.03 0.05 0.16

95% CI ±1,077 ±0.031 ±0.006 ±0.010 ±0.019 

Cotton, 

2015

Cont. till 4,543 0.62 0.02 0.03 0.06 0.03

95% CI ±386 ±0.016 ±0.017 ±0.018 ±0.014 

Alt. no/strip-till 2,109 0.29 0.16 0.12 0.22 0.06

95% CI ±440 ±0.063 ±0.047 ±0.077 ±0.030 

Cont. no/strip-till 679 0.09 0.17 0.02 0.27 0.06

95% CI ±227 ±0.104 ±0.013 ±0.084 ±0.053 

All tillage 7,472 0.08 0.06 0.12 0.04

95% CI ±294 ±0.023 ±0.013 ±0.030 ±0.011 

Soybeans, 

2012

Cont. till 30,420 0.44 0.07 0.03 NA 0.04

95% CI ±1,605 ±0.021 ±0.007 ±0.011 

Alt. no/strip-till 23,634 0.34 0.23 0.13 NA 0.04

95% CI ±1,959 ±0.028 ±0.022 ±0.019 

Cont. no/strip-till 14,638 0.21 0.06 0.02 NA 0.01

95% CI ±1,544 ±0.022 ±0.012 ±0.011 

All tillage 69,246 0.12 0.06 NA 0.03

95% CI ±949 ±0.016 ±0.009 ±0.009 

Wheat, 

2017

Cont. till 15,443 0.42 0.09 0.04 0.01 0.02

95% CI ±2,206 ±0.024 ±0.023 ±0.005 ±0.016 

Alt. no/strip-till 10,839 0.30 0.26 0.07 0.01 0.02

95% CI ±1,981 ±0.054 ±0.028 ±0.005 ±0.017 

Cont. no/strip-till 10,259 0.28 0.28 0.04 0.04 0.01

95% CI ±1,031 ±0.089 ±0.031 ±0.025 ±0.009 

All tillage 36,993 0.19 0.05 0.02 0.02

95% CI ±1,018 ±0.028 ±0.013 ±0.007 ±0.009 

1Observations with partial crop histories are excluded, so acreage estimate for "All tillage" is less than for all ARMS observations. However, "All tillage" includes some observations for which tillage history could not be established, so it is greater than 

the sum of continuous tillage, alternating no-till/strip-till and continuous no-till/strip-till.

NA = data not available for these surveys. CI = confidence interval.

Source: USDA, Agricultural Resources Management Survey data for 2012, 2015, 2016, and 2017. 
14

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

Table 1b

Conservation cropping and practices the reduce residue by crop and continous tillage, 

alternating no-till/strip-till, and continuous no-till/strip-till

Crop Tillage Acres

Share of acres 

by crop Fallow Residue harvested Grazing2

Share of planted acres by tillage practice

 (95% confidence interval)

Corn, 2016 Cont. till 44,058 0.55 0.00 0.04 0.06

95% CI ±2,388 ±0.002 ±0.011 ±0.019 

Alt. no/strip-till 21,747 0.27 0.02 0.04 0.16

95% CI ±2,596 ±0.010 ±0.020 ±0.034 

Cont. no/strip-till 14,203 0.18 0.01 0.02 0.23

95% CI ±1,734 ±0.007 ±0.014 ±0.059 

All tillage1 81,903 0.01 0.04 0.12

95% CI ±1,077 ±0.003 ±0.007 ±0.019 

Cotton, 

2015

Cont. till 4,543 0.62 0.02 NA NA

95% CI ±386 ±0.013 

Alt. no/strip-till 2,109 0.29 0.01 NA NA

95% CI ±440 ±0.016 

Cont. no/strip-till 679 0.09 0.07 NA NA

95% CI ±227 ±0.099 

All tillage 7,472 0.02 NA NA

95% CI ±294 ±0.012 

Soybeans, 

2012

Cont. till 30,420 0.44 0.01 NA NA

95% CI ±1,605 ±0.003 

Alt. no/strip-till 23,634 0.34 0.01 NA NA

95% CI ±1,959 ±0.004 

Cont. no/strip-till 14,638 0.21 0.01 NA NA

95% CI ±1,544 ±0.015 

All tillage 69,246 0.01 NA NA

95% CI ±949 ±0.003 

Wheat, 

2017

Cont. till 15,443 0.42 0.13 0.05 0.25

95% CI ±2,206 ±0.032 ±0.015 ±0.064 

Alt. no/strip-till 10,839 0.30 0.11 0.07 0.19

95% CI ±1,981 ±0.030 ±0.024 ±0.069 

Cont. no/strip-till 10,259 0.28 0.16 0.03 0.11

95% CI ±1,031 ±0.040 ±0.011 ±0.039 

All tillage 36,993 0.13 0.05 0.19

95% CI ±1,018 ±0.015 ±0.009 ±0.032 

1Observations with partial crop histories are excluded, so acreage estimate for "All tillage" is less than for all ARMS observations. However, "All tillage" includes some observations for which tillage history could not be established, so it is greater than 

the sum of continuous tillage, alternating no-till/strip-till and continuous no-till/strip-till.

2On corn, residue is commonly grazed; Wheat grazing usually occurs when wheat is growing in early spring.

NA = data not available for these surveys. CI = confidence interval.

Source: USDA, Agricultural Resources Management Survey data for 2012, 2015, 2016, and 2017. 
15

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

How Tillage Estimates Differ Using STIR and Residue 

Methods 

In the past, ERS classified tillage practices using an estimate of soil residue cover remaining at 

planting time, which focused on the “keep it covered” approach to reducing soil erosion. However, 

because a number of other practices influence residue cover estimates, the STIR is more likely to 

accurately characterize soil disturbance due to tillage. Nonetheless, a key question is how these 

methods actually differ in classifying the tillage systems. Our method of determining no-till does 

not change (i.e., the absence of tillage operations), so no-till estimates are unchanged.

Residue Cover Method . Data on the previous crop and pre-planting tillage operations, obtained 

from the ARMS survey, have been used to estimate the extent of conservation tillage since 1988 

(USDA-ERS, 1993; Bull, 1993). This method for characterizing tillage systems uses percent residue 

cover on the field at planting.10 Fields that have more than 30 percent cover on the field and have a 

tillage operation are categorized as mulch tillage. Fields that do not have any tillage operations are 

categorized as no-till. These two categories together constitute conservation tillage. To estimate 

percent residue cover that remains at planting, we start with an estimate of residue cover from the 

previous crop and then estimate the reduction in residue for each tillage pass. Residue from hay, 

including alfalfa, leaves the soil almost entirely (90-95 percent) covered (table 2). Corn, sorghum, 

and wheat residues also leave the soil mostly covered (85 percent). Soybeans leave a moderate 

amount of residue (60 percent). Corn and sorghum silage (10 percent) and cotton (35 percent) leave 

relatively little residue. 

Each tillage pass reduces residue coverage. The percentage reduction depends on the tillage implement and whether residue from the previous crop is “fragile.” One pass with a moldboard plow, for 

example, reduces residue coverage by 95 percent. In contrast, a stubble mulch plow—a conservation 

tillage implement—reduces nonfragile residue coverage by only 15 percent. Fragile residue (e.g., 

soybeans) decomposes more easily and has higher residue reduction rates with each tillage pass. For 

example, one pass with a stubble mulch plow reduces fragile residue by 45 percent, compared to 15 

percent for non-fragile residue. Due to differences in the previous planted crop, two fields that are 

tilled the same way can be categorized into different tillage systems.

Table 2

Surface residue coverage and fragility for common field crops

Surface residue coverage

Fragility Low (<40%) Medium (40-70%) High (>70%)

Low Cotton, corn silage, sorghum silageRice, canola Hay, corn, wheat, small 

grains, sorghum

High Sugarbeets, beans, peas, 

peanuts

Soybeans

10This method has no relation to the method used to determine a conservation crop rotation. Conservation rotation is 

broader than just the amount of residue produced in a single year. 
16

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

Because the residue method relies on the previous crop, and different crops are grown in rotations 

together, the impacts of switching tillage methods will vary from crop to crop. In addition, certain 

types of tillage equipment, with differing impacts on surface residue and soil disturbance, may 

be used on one crop more than another. Finally, because the residue method relies on tillage up to 

planting and the STIR method relies on tillage and other field operations for the entire season, postplanting operations (e.g., row cultivation for weed control) could affect differences in categorization. 

Results. In wheat (2017) and soybeans (2012), the STIR method categorizes more fields as conventionally tilled than does the residue-based method (fig. 5). In corn (2016) and cotton (2015), the 

STIR method categorizes more fields as mulch tilled than the residue-based method. 

Figure 5

Tillage practice estimates using STIR and estimated residue at planting, as a share of 

planted acres

Percent of planted acres

0

10

20

30

40

50

60

70

80

Conv Mulch No-till Conv Mulch No-till Conv Mulch No-till Conv Mulch No-till

Wheat, 2017 Corn, 2016 Soybeans, 2012 Cotton, 2015

Residue/No tillage ops STIR/No tillage ops

Note: No-till is based on the absence of tillage operations reported in ARMS. Mulch till with the residue method is indicated 

when at least 30 percent of the soil surface is estimated to be covered with residue just prior to planting with some tillage 

operations. Mulch till with the Soil Tillage Intensity Rating (STIR) method is indicated when the STIR measure is less than 80 

(for the entire season) with some tillage operations. 

Source: USDA, Agricultural Resources Management Survey data for 2012, 2015, 2016, and 2017..

Classification of tillage using the residue method depends on the amount of residue produced by 

the previous crop and whether the residue is “fragile,” meaning it breaks down easily with tillage. 

Where a crop that produces a high level of non-fragile residue, such as corn for grain or wheat, 

was planted in the previous year, a conservation tillage classification is more likely using the 

residue method than the STIR method. Where a medium- or low-residue crop or a crop with fragile 

residue—such as soybeans, cotton, or silage—was planted in the previous year, a conventional 

tillage classification is more likely using the residue method than the STIR method. The majority 

of corn fields follow a medium-residue crop, most commonly soybeans. These fields are more than 

twice as likely to be categorized as conventional till using the residue method when compared to the 

STIR method (fig. 6a). Soybean fields leave relatively little residue cover on the field (65 percent), 

and soybean residue is relatively fragile. Soybeans often follow corn, a high-residue crop. Because of 

high starting residue cover on these fields, the residue method is more likely to categorize the tillage 

system as mulch till than is the STIR method (fig. 6b). On soybean fields that follow a mediumresidue crop, the residue method is more likely to categorize the tillage system as conventional. The 
17

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

story for wheat is similar to that for soybeans. Wheat often follows a high-residue crop (fig. 6c), 

so the residue method is less likely to categorize the tillage system as conventional. Finally, cotton 

fields (fig. 6d) commonly follow a low-residue crop, making a conventional tillage categorization 

more likely when using a residue-based method. 

Figure 6

Residue from prior crop and residue-based tillage versus STIR-based classifications 

Percent of planted acres

0

10

20

30

40

50

60

70

80

90

Residue STIR Residue STIR Residue STIR

High-residue

prior crop

Mediumresidue 

prior crop

Low-residue

prior crop

0

10

20

30

40

50

60

70

80

90

Residue STIR Residue STIR Residue STIR

0

10

20

30

40

50

60

70

80

90

Residue STIR Residue STIR Residue STIR

0

10

20

30

40

50

60

70

80

90

Residue STIR Residue STIR Residue STIR

a. Corn, 2016 b. Soybeans, 2012

Percent of planted acres

c. Wheat, 2017 d. Cotton, 2015

Conventional Mulch No-till

High-residue

prior crop

Mediumresidue 

prior crop

Low-residue

prior crop

High-residue

prior crop

Mediumresidue 

prior crop

Low-residue

prior crop

High-residue

prior crop

Mediumresidue 

prior crop

Low-residue

prior crop

Percent of planted acres Percent of planted acres

Notes: Primary high-residue crops include hay, corn, wheat, sorghum, and barley. The primary medium-residue crop is soybeans. Primary low-residue crops are cotton and any other crop harvested for silage. STIR = Soil Tillage Intensity Rating.

Source: USDA, Agricultural Resources Management Survey data for 2012, 2015, 2016, and 2017.
18

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

Conclusions

Conservation tillage is widely used in the production of major field crops, but adoption of conservation tillage—including no-till and strip-till—varies across crops and regions. Conservation tillage in 

general and no-till in particular increased significantly in wheat across the 2004 and 2009 surveys, 

but growth slowed over 2009-17. Growth in conservation tillage and no-till were both quite modest 

in corn and cotton. In soybeans, 2002-06 growth in overall conservation tillage and no-till was 

followed by an apparent decline in no-till from 2006 to 2012. 

Within crops, there is also significant regional variation in conservation tillage and no-till adoption. Temporally, no-till/strip-till was used at least once on nearly 50 percent of land in the most 

recent surveys for the four major commodity crops. In contrast, continuous no-till was applied to 

only about 20 percent of acreage is these same surveys. In general, variation in tillage intensity may 

reflect crop choice, climate, soil productivity, soil erodibility, drainage, and soil topography (Ogle et 

al., 2012; Toliver et al., 2012; Wade et al., 2015; Wade and Claassen, 2017). 

There is some evidence to suggest that farmers who use no-till are also more likely to use conservation crop rotations and cover crops. These practices may be viewed, at least by some farmers, as 

complementary because of their combined effect on soil health and productivity. The relatively high 

rate of conservation crop rotations by corn producers may be largely due to the fact that corn is a 

high-residue crop and (unlike wheat, the other common high-residue crop) is often grown in rotation with a legume (soybeans), although a simple corn-soybean rotation would not meet all of the 

criteria for a conservation rotation. Practices that could lead to higher residue, including cover crops 

and double cropping, are less widely adopted on all crops (except for cover crops on cotton farms). 

Some practices that reduce residue production or remove it from the field after harvest are adopted 

more often, including fallowing in wheat (13 percent of acres), residue grazing in corn (12 percent), 

and residue harvest in corn (4 percent) and wheat (5 percent). At present, there is little evidence to 

indicate whether farmers consider conservation tillage and residue practices to be complementary in 

production. That is particularly true for cover crop practices where adoption, although increasing, is 

still very low. 
19

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

References 

Allen, R.R., and C.R. Fenster. 1986. “Stubble-mulch equipment for soil and water conservation in 

the Great Plains,” Journal of Soil and Water Conservation 41:11-16.

Bergtold, J.S., S. Ramsey, L. Maddy, and J.R. Williams. 2017. “A Review of Economic 

Considerations for Cover Crops as a Conservation Practice,” Renewable Agriculture and Food 

Systems, pp. 1-15.

Borchers, A., E. Truex-Powell, S. Wallander, and C. Nickerson. 2014. Multi-Cropping Practices: 

Recent Trends in Double Cropping, EIB-125, U.S. Department of Agriculture, Economic 

Research Service, May.

Bull, L. 1993. “Residue and Tillage Systems for Field Crops.” Staff Report AGES 9310, U.S. 

Department of Agriculture, Economic Research Service, July.

Conservation Tillage Information Center (CTIC). Tillage Type Definitions. 

Davey, K., and W. H. Furtan. 2008. “Factors that affect the adoption decision of conservation tillage 

in the Prairie Region of Canada,” Canadian Journal of Agricultural Economics 56: 257-275.

Ding, Y., K. Schoengold, and T. Tadesse. 2009. “The impact of weather extremes on agricultural 

production methods: does drought increase adoption of conservation practices?” Journal of 

Agricultural and Resource Economics 34(3): 395-411.

Givens, W.A., D.R. Shaw, G.R. Kruger, W.G. Johnson, S.C. Weller, B.G. Young, R.G. Wilson, M.D. 

Owen, and D. Jordan. 2009. “Survey of tillage trends following the adoption of glyphosate-resistant crops,” Weed Technology 23(1):150-155.

Haynes, R.J., and R. Naidu. 1998. “Influence of Lime, Fertilizer and Manure Applications on 

Soil Organic Matter Content and Soil Physical Conditions: A Review,” Nutrient Cycling in 

Agroecosystems 51(2): 123-137.

Horowitz, J., R. Ebel, and K. Ueda. 2010. “No-Till” Farming Is a Growing Practice. EIB-170, U.S. 

Department of Agriculture, Economic Research Service, November.

Karlen, D.L., N.C. Wollenhaupt , D.C. Erbach , E.C. Berry, J.B. Swan, N.S. Eash, and J.L. Jordah. 

1994. “Crop residue effects on soil quality following 10-years of no-till corn,” Soil & Tillage 

Research 31: 149-167.

Karlen, D.L., S.J. Birrell, J,M.F. Johnson, S.L. Osborne, T.E. Schumacher, G.E. Varvel, R.B. 

Ferguson, J.M. Novak, J.R. Fredrick, J.M. Baker, J.A. Lamb, P.R. Adler, G.W. Roth, and E.D. 

Nafziger. 2014. “Multilocation Corn Stover Harvest Effects on Crop Yields and Nutrient 

Removal,” BioEnergy Research 7(2): 528-539.

Mezzatesta, M., D. Newburn and R. Woodward. 2013. “Additionality and the Adoption of Farm 

Conservation Practices,” Land Economics 89(4): 722-742.

Moebius-Clune, B.A., H.M. van Es, O.J. Idowu, R.R. Schindelbeck, D.J. Moebius-Clune, D.W. 

Wolfe, G.S. Abawi, J.E. Thies, B.K. Gugino, and R. Lucey. 2008. “Long-Term Effects of 
20

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

Harvesting Maize Stover and Tillage on Soil Quality,” Soil Science Society American Journal 72: 

960-969.

Moore-Kucera, Jennifer. 2018. “Latest Insights on Soil Biology as Influenced by Soil Management.” 

Presentation at SARE Our Farms, Our Future Conference, April 3.

Nielsen, D.C., and F.J. Calderón. 2011. “Fallow Effects on Soil,” in Soil Management: Building a 

Stable Base for Agriculture, J.L. Hatfield and T.J. Sauer, eds. Madison, WI: American Society of 

Agronomy and Soil Science Society of America.

Norfleet, M. Lee. 2018. U.S. Department of Agriculture, Natural Resources Conservation Service, 

personal communication.

Ogle, S. M., A. Swan, and K. Paustian. 2012. “No-till management impacts on crop productivity, 

carbon input and soil carbon sequestration,” Agriculture, Ecosystems & Environment 149(1): 

37-49.

Pautsch, G., L. Kurkalova, B. Babcock, and C. Kling. 2001. “The Efficiency of Sequestering Carbon 

in Agricultural Soils,” Contemporary Economic Policy 19(2): 123-34.

Perry, E., G. Moschini, and D. Hennessy. 2016. “Testing for Complementarity: Glyphosate Tolerant 

Soybeans and Conservation Tillage,” American Journal of Agricultural Economics 98(3): 

765-784.

Rawls, W.J., Y.A. Pachepsky, J.C. Ritchie, T.M. Sobecki, and H. Bloodworth. 2003. “Effect of soil 

organic carbon on soil water retention,” Geoderma 116: 61-76.

Rosburg, A., J. McFadden, and J. Miranowski. 2017. “Managing Feedstock Supply Risk for the 

Development of a U.S. Stover Biofuel Industry,” BioEnergy Research 10(3): 671-687.

Russel, J.C. 1976. Some historical aspects of stubble mulch tillage, Publication 77, Great Plains 

Agricultural Council, Lincoln, NE. 

Toliver, D.K., J.A. Larson, R.K. Roberts, B.C. English, D.G. De La Torre Ugarte, and T.O. West. 

2012. “Effects of no-till on yields as influenced by crop and environmental factors,” Agronomy 

Journal 104(2): 530-541.

U.S. Department of Agriculture, Economic Research Service. 1993. Agricultural Resources: Inputs 

Situation and Outlook, AR-29, Feb.

U.S. Department of Agriculture, Economic Research Service. 2017. “Major Land Uses” data 

product, Summary Table 3, available online.

U.S. Department of Agriculture, Economic Research Service. 2018. ARMS Farm Financial and 

Crop Production Practices, Documentation, available online. 

U.S. Department of Agriculture, Natural Resources Conservation Service. 2008. “Soil Tillage 

Intensity Rating (STIR).” 

U.S. Department of Agriculture, Natural Resources Conservation Service. 2014a. “Conservation 

Practice Standard Code 328: Conservation Crop Rotation.” 
21

Tillage Intensity and Conservation Cropping in the United States, EIB-197

USDA, Economic Research Service

U.S. Department of Agriculture, Natural Resources Conservation Service. 2014b. Soil Health 

Literature Summary—Effects of Conservation Practices on Soil Properties on Areas of Cropland 

data product. 

U.S. Department of Agriculture, Natural Resources Conservation Service. 2014c. NRCS Cover Crop 

Termination Guidelines. 

U.S. Department of Agriculture, Natural Resources Conservation Service. 2016. “Conservation 

Practice Standard Code 345: Residue and tillage management, reduced tillage.” 

U.S. Department of Agriculture, Natural Resources Conservation Service. 2017. Healthy, productive 

soils checklist for growers. Fact Sheet, March. 

U.S. Department of Agriculture, Natural Resources Conservation Service. 2018a. “Soil Health” topic 

page. 

U.S. Department of Agriculture, Natural Resources Conservation Service. 2018b. Soil Health 

Assessment. 

Unger, P.W., and R.L. Baumhardt. 2001. “Historical development of conservation tillage in the 

Southern Great Plains,” in Presentations at the 24th Annual Southern Conservation Tillage 

Conference for Sustainable Agriculture, Oklahoma City, OK (pp. 9-11), July.

Wade, T., R. Claassen, and S. Wallander. 2015. Conservation-Practice Adoption Rates Vary Widely 

by Crop and Region, EIB-147, U.S. Department of Agriculture, Economic Research Service, Dec.

Wade, T., and R. Claassen. 2017, “Modeling No-Tillage Adoption by Corn and Soybean Producers: 

Insights into Sustained Adoption,” Journal of Agricultural and Applied Economics 49(2): 

186-210.