Long-Term Agroecological Research

The Long-Term Agroecological Research (LTAR) experiment at the ISU Neely-Kinyon Research and Demonstration Farm near Greenfield, Iowa, was set up in 1998, the capstone of the Organic Ag program at Iowa State University. It is one of the longest running comparisons of organic and conventional crops in the country.

The Leopold Center has supported the LTAR project since it began. The Center's investment has been multiplied four-fold as leveraged funding to obtain additional grants from other agencies and the organic industry. During the LTAR project's first dozen years, Leopold Center support resulted in 32 peer-reviewed publications, nine ISU Extension publications, 31 workshops, 65 field days and work by 20 international visiting scientists. Research continues with competitive grant funding from the Leopold Center and other sources.

The goals of the LTAR Team:

To examine the agronomic, economic and environmental performance of conventional and organic systems, using certified organic production practices, including:

  • Soil and water quality
  • Energy use
  • Yields and economic returns
  • Weed management

LTAR is a randomized, replicated comparison of the following rotations:

  • Conventional corn-soybean (2 year)
  • Organic corn-soybean-oats/alfalfa (3 year)
  • Organic corn-soybean-oats/alfalfa-alfalfa (4 year)
  • Organic soybean-wheat/red clover (2 year)


Related grant projects

For more information, contact Kathleen Delate, ISU Horticulture/Agronomy, kdelate@iastate.edu, (515) 294-7069.