Submitted to: Western Society of Weed Science
Publication Type: Research Notes
Publication Acceptance Date: December 1, 2005
Publication Date: March 10, 2006
Citation: Anderson, R.L. 2006. A management approach based on disrupting weed population growth. Western Society of Weed Science. pp. 204-205. Interpretive Summary: Producers in the Central Great Plains are searching for a new way of controlling weeds, in contrast with their current herbicide-based system. In this region, cropping systems are rapidly changing because of no-till systems; a greater diversity of crops now is grown in the rotation. Crop diversity provides an opportunity for producers to develop a weed management system based on disrupting weed population dynamics. With this approach, producers effectively control weeds with 50% less herbicide inputs, thus reducing costs as well as pesticide entry to the environment. This approach relies on cultural tactics in five categories designed to disrupt weed population growth, with diverse crop rotations being a key component. Producers are now growing some crops in their rotations without herbicides because the weed community density in their fields are so low.
Technical Abstract: No-till systems have enabled producers to change crop rotations in the semiarid Central Great Plains. Previously, winter wheat (Triticum aestivum L.)-fallow was the prevalent rotation; now producers grow warm-season crops along with winter wheat and fallow. Initially, weed management was difficult in no-till rotations. However, an ecological approach to weed management, which integrates knowledge of weed population dynamics with cultural tactics and long-term planning, has enabled producers to control weeds with 50% less herbicides. This paper explains the cultural tactics and ecological reasoning that led to this successful approach; our goal is to provide insight and ideas for other scientists and producers to plan multi-tactic weed management. The ecological approach emphasizes three goals related to weed population dynamics: enhancing natural loss of weed seeds in soil, reducing weed seedling establishment, and minimizing seed production by established plants. Cultural tactics used in this approach can be grouped into five categories: rotation design, crop sequencing, no-till, crop residue management, and competitive crop canopies; success of the approach requires cultural tactics in each category.