Effects of Weed Communities in Conventional and Organic Agricultural Systems.

View the project final report

Commodities

• Agronomic: wheat

Practices

• Crop Production: conservation tillage
• Education and Training: on-farm/ranch research
• Farm Business Management: whole farm planning
• Natural Resources/Environment: biodiversity
• Pest Management: integrated pest management, weed ecology
• Production Systems: agroecosystems, transitioning to organic

The negative effects of agriculture have become a growing concern in recent years (Tilman, 1999; van der Werf and Petit, 2002; Biao et al., 2003). To address these concerns, it has become clear that it will be necessary to examine ecological processes in order to meet the needs of the future while minimizing negative environmental and economic impacts. By examining weed communities in organic and conventional systems we hope to elucidate some of the ecological processes that occur within these systems, and to identify those that might contribute to the development of sustainable weed management practices. Specifically, we will examine weed diversity, weed spatial patterns, and weed-crop competition in spring wheat systems. Our goal is to increase our understanding of the importance of the distribution and diversity of weed communities in conventional and organic spring wheat systems. In addition, we hope to determine if these differences have an impact on yield, and if it is possible to employ weed community structure as a sustainable management alternative. Understanding the functional importance of weed community characteristics might be a valuable tool for weed management. If this proves to be the case, it would most certainly reduce the economic costs to farmers and the negative environmental impacts that are associated with the use of tillage and herbicides. The information generated by this research will then be made available to farmers via extension publications and talks and through presentations at conferences and local field days.

• Objective 1: Assess the spatial and temporal patterns of weed density and weed species richness in conventional input and organically managed spring wheat systems. Objective 2: Quantify the effects of weed species richness and weed density on the growth and yield of spring wheat.