Page Banner

United States Department of Agriculture

Agricultural Research Service

Title: Improving Soil Quality: Implications for Weed Management

Authors
item Gallandt, E - WASHINGTON STATE UNIV.
item Liebman, M - UNIVERSITY OF MAINE
item Huggins, David

Submitted to: Journal of Crop Production
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 1, 1998
Publication Date: N/A

Interpretive Summary: Our current crop production systems rely heavily on herbicides to control weeds. Many unexplored opportunities exist, however, to manipulate the soil environment and design cropping systems that create weed suppressive conditions. This ecological approach to weed management will require a greater understanding of key processes that define the relationships between the weed environment, including soil, and weed establishment and survival. We established weed-related soil management objectives as: (i) reducing the persistence of seeds in the soil; (ii) reducing the abundance of soil resources such as water, nutrients, and light available for weed establishment; and (iii) reducing crop yield loss caused by a given density of weeds. We further identified soil factors that can be managed to achieve these goals including: (i) chemical, physical, and biological conditions that affect resources required for weed seed germination, establishment and growth; and (ii) habitat for herbivores and pathogens that attack weed seeds and seedlings; and (iii) chemical toxin production. We believe that this information provides a framework for scientists and agricultural professionals to evaluate soil management effects on weed establishment and persistance.

Technical Abstract: Future advancements in crop production will rely on increased understanding of ecological principles that control interactions among cropping system components. Our interest in linking soil quality and weed management derives from the belief that greater understanding of key processes and properties that define soil-weed relationships will lead to the design of agroecosystems with greater capacity and opportunity to suppress weeds. W identified seed-bank persistence, seedling establishment, and interspecific interference as key processes that affect annual weed population dynamics. We then examined how soil processes and properties can affect each of these factors and how, in turn, soil improving management practices and cropping system design may affect weed dynamics. We established weed-related soil management objectives as: (i) reducing the persistence of seeds in the soil; (ii) reducing the abundance of "safe-sites" for weed establishment and the filling of available sites; and (iii) reducing crop yield loss caused by a given density of weeds. Soil factors that can be managed to achieve these goals include: (i) chemical, physical, and biological conditions that affect resources required for weed seed germination, establishment and growth; and (ii) habitat for herbivores and pathogens that attack weed seeds and seedlings; and (iii) phytotoxin production. We concluded that many as yet unexplored opportunities exist to manipulate the soil environment and to design cropping systems that create multiple weed suppressive conditions at critical junctures of weed seed-bank persistence, establishment, and interference.

Last Modified: 8/29/2014