Improving Soil Health and Microbial Activity through Zone Tillage and Innovative Cover Cropping Strategies

Project Overview

Project Type: Graduate Student
Funds awarded in 2014: $9,995.00
Projected End Date: 12/31/2015
Grant Recipient: University of Minnesota
Region: North Central
State: Minnesota
Graduate Student:
Faculty Advisor:
Dr. Julie Grossman
University of Minnesota

Annual Reports


  • Vegetables: eggplant


  • Crop Production: conservation tillage
  • Education and Training: demonstration, workshop
  • Natural Resources/Environment: biodiversity, soil stabilization
  • Soil Management: green manures, nutrient mineralization, organic matter, soil analysis, soil microbiology, soil quality/health

    Proposal abstract:

    Organic growers face a challenging set of guidelines, both prohibiting them from using synthetic herbicides and encouraging them to utilize cover crops in order to maintain ground cover and meet crop nutrient needs.  The resulting intensive tillage that organic farmers often use to control weeds, incorporate cover crop residue, and prepare seedbeds is detrimental to soil structure and biology, as well as to the greater environment by accelerating nutrient losses and soil erosion to sensitive water bodies.  Adopting no-till practices has proven difficult for organic growers, and the long, cold winters in the Upper Midwest exacerbate these difficulties with periods of decreased soil microbial activity and delayed soil warming.  Zone tillage is an overlooked reduced tillage strategy where rows are tilled and interrows are maintained with ground cover, and may help address problems organic growers face with both weed suppression and crop nutrient needs.  The purpose of the proposed research is to evaluate both crop productivity and soil biological responses to different zone tillage methods in two organic vegetable production systems, one using a winter rye/hairy vetch winter annual cover crop and another with a biennial red clover living mulch, with the goal of reconciling organic systems with reduced tillage.

    Project objectives from proposal:

    Our two learning outcomes and two action outcomes emphasize understanding how zone tillage impacts microbial and organic matter assays, and extend learned information to growers and students.  We will do this by measuring indicators of soil health, including microbial biomass, permanganate oxidizable carbon, particulate organic matter, and potentially mineralizable nitrogen.  An initial brief preliminary survey will be extended to farmers at the 2015 MOSES conference to evaluate attitudes toward zone tillage and perennial cover crops.  A demonstration day during the first growing season will allow at least 20 local farmers to observe and learn about these systems and provide feedback. Results will enable organic growers to maximize cover crop advantages as ground cover and fertility sources, as well as conserve soil structure, tighten the N cycle, and reducing environmental pollution from sediment and nutrient losses.  Environmental benefits from reduced tillage and extended cover cropping strategies will become apparent through improved soil and water quality and crop productivity in the long-term.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.