Weed Supression with Winter Annual Cover Crops in Potato

Project Overview

Project Type: Graduate Student
Funds awarded in 2010: $9,950.00
Projected End Date: 12/31/2012
Region: North Central
State: North Dakota
Graduate Student:

Annual Reports


  • Agronomic: potatoes


  • Crop Production: cover crops, irrigation, no-till
  • Pest Management: allelopathy, integrated pest management, physical control, weed ecology
  • Production Systems: holistic management, organic agriculture
  • Soil Management: green manures, organic matter, nutrient mineralization, soil quality/health

    Proposal abstract:

    Integration of cover crops is scarce in conventional agriculture today. With the use of pesticides, fertilizer, and crop rotation, most major production problems can be overcome. However, more growers are beginning to consider the use of cover crops as they reflect on the importance of soil retention, soil quality and environment quality, as well as alternate methods for fertility management and pest control. Cover crops are heavily relied upon in organic and sustainable agriculture systems. These systems continue to increase in acreage each year, with North Dakota ranked second in acreage for organic crops. Weed control in organic potato production relies on the effectiveness of cultivation, harrowing, and weed suppressing varieties. Unfortunately, in the Red River Valley, regular precipitation and slow soil drying due to the heavy soil texture, makes timely cultivation difficult and often impossible. A potential alternative, which utilizes early season weed suppression, is through the use of winter annual cover crop species. Unfortunately, cover crop research in the Northern Plains region is limited. The proposed research will determine the effectiveness of cover crop species and kill methods on weed suppression in potato. Cover crop performance will be evaluated with respect to cover crop biomass accumulation, soil water content, nitrogen cycling, weed suppression, subsequent potato yield and grade. The expected outcome of this research will provide greater awareness among producers of the benefits of cover crops, expand the use of cover crops, and demonstrate the benefits and limitations when incorporating a cover crop into a sustainable potato production system. Results from this project will be made available regionally to potato growers through extension articles and websites, grower meetings and field days; and nationally as publications in scientific journals.

    Project objectives from proposal:

    1) Short-Term Outcomes: The cover crop weed suppression project in potatoes has the ability to greatly impact the weed control knowledge of growers currently producing organic potatoes in North Dakota and Minnesota. Grower’s knowledge of this research will expand the interest in organic potato production and show others new technology and science that should improve their operations. The awareness of cover crop benefits beyond weed control should increase the interest of adopting cover crops in other production systems.

    2) Intermediate-Term Outcomes: This project will demonstrate the ability of cover crops to bring the nitrogen towards the soil surface for plant use and to reduce weed establishment. It will provide a new method of weed control for organic potato producers in this region without decreasing yields. It is anticipated that we will be able to build on the success of this project to show other producers the benefits of cover crops to the soil and thereby increase profitability and sustainability in their production system.

    3) Long-Term Outcomes: The ultimate goal of the cover crop for weed suppression project is a positive effect to the whole system of organic agriculture. Not only would potato growers in North Dakota and Minnesota be impacted by the research, but growers throughout pertinent potato growing regions in the United States and other countries as well. Systemic changes could be achievable with the success of this research. The organic potato industry would have greater success with potentially higher yields using cover crops for weed control as well as increasing soil quality and sustainable production practices. In organic agriculture, pests and nutrient deficiencies of all sorts have the potential to decrease yields and create major production problems for growers. Cover crops are the link which could serve multiple purposes in organic agriculture. A great aspect of this potential research is its ability to add knowledge to an integrated cover crop system for growers that have been content with conventional production practices, paving the way for more sustainable practices and the future of organic agriculture.

    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.