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Cover Crop and Tillage Transect Data

The state of Indiana has conducted periodic surveys of agricultural land since 1989. These surveys are primarily designed to gather information on various agricultural practices, including tillage and cover crops. Currently the various partners from the Indiana Conservation Partnership (ICP), led by the Indiana State Department of Agriculture (ISDA) conduct an annual survey in each county in the state to estimate the adoption of cover crops, and post-harvest tillage.

Click on counties in the map below to see statistics from the 2021 Conservation Survey. Click the layers list icon (stacked squares) in the top right of the map to turn layers on and off.

  • About

    According to a recent conservation survey, Indiana farmers have set a conservation record this year by planting an estimated 1.5 million acres of overwinter living covers, the largest amount ever recorded by an Indiana Conservation Partnership survey.

    Overwintering living covers (i.e. - cover crops and small grains, like wheat) are known for their environmental benefits. Cover crops and small grains help increase organic matter in the soil and improve overall soil health by adding living roots to the soil more months of the year. Cover crops also improve water infiltration into the soil, while other covers, like legumes serve as natural fertilizers.

    Although the conservation transect doesn’t differentiate between cover crops and small grains, Indiana farmers typically plant fewer than 200,000 acres of small grains annually, so cover crops vastly dominate the 1.5 million estimated acres. With the exception of corn and soybeans, cover crops are planted on more acres than any other commodity crop in Indiana. Cover crops are typically planted in the fall after harvest, and designed to protect the soil and keep roots in the ground throughout the winter, which improves soil health and helps filter water runoff.

    As a result of the cover crops planted last year, it is estimated that 1.6 million tons of sediment was prevented from entering Indiana’s waterways, which is enough sediment to fill more than 453 Olympic-size swimming pools. Overwintering covers also prevented 4.1 million pounds of nitrogen and over 2 million pounds of phosphorus from entering Indiana's waterways.

    The conservation survey also showed that 62% of farmed acres were not tilled and 18% had employed reduced tillage after the 2020 harvest. This early spring survey is not intended to quantify pre-planting tillage.

    The conservation transect is a visual survey of cropland in the state. It was conducted between March and April 2021 by members of the Indiana Conservation Partnership, including the USDA Natural Resources Conservation Service, the Indiana State Department of Agriculture, Indiana’s Soil and Water Conservation Districts and Purdue Extension, as well as Earth Team volunteers, to show a more complete story of the state’s conservation efforts.

  • Current Data and Maps
  • Methods

    Conservation surveys are conducted at the county level for each county in the state, except for Marion county due to insufficient agricultural land. Conservation surveys consist of taking windshield observations of a sample of agricultural fields throughout a county. The locations of the observations fall along a preselected route that is used from year to year. The routes are drawn to be spatially dispersed throughout the county, and pass through all soil regions that are heavily used for agriculture. Points are preselected along the route, at approximately half mile intervalsAt each point an observation is made on the right and left side of the road if agricultural land is available.

    An observation of an individual field consists of several variables: crop during the previous season, tillage type, and cover crop status. Each variable is categorical, the categories for crop during previous season are corn, soybeans, small grains, hay/pasture/CRP plantings, fallow, and unable to be determined. The categories for tillage type are not-tilled, reduced-tilled, conventional tilled, and unknown / not applicable. Cover crop observations are either present or absent.

    Each survey is completed no sooner than 10 days after the first period 3 consecutive daytime temperatures above 40° F in that county. Using this timing regime was designed to better capture living covers on the ground, and make sure that timing of the surveys was uniform across counties.

    The number of observations that contain a specified parameter are divided by the total number of observations to calculate a proportion. This proportion is an estimate of the frequency of the parameter. Acreage of the parameter can be calculated by multiplying the proportion by the number of acres of agricultural, which are estimated by the National Agricultural Statistic Service Cropland Data Layer (CDL). The CDL is a uses satellite imagery to calculate crop specific land cover.

    Click here for historical transect methodology (1990-2019).

  • Contact Us

    For more information about the Conservation Survey or to request tabular data, please contact Sam Stroebel.

Historical Data

As conservation work has changed over time, the conservation survey has been modified to better measure current conservation goals. At its inception the transect was designed to measure tillage and residue cover. In 2011 the survey efforts were expanded to include collecting data on cover crops. In 2014, a second fall survey was started as a specific effort to measure cover crops.