Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 6/3/2005
Publication Date: 10/15/2005
Citation: Anderson, R.L. 2005. A new approach to weed management, based on ecology. In: Kosolap, N.P., editor. Science of Herbology. Kiev, Ukraine: Ukraine National Agricultural University Press. p. 281-302. Interpretive Summary: Rain-fed crop production is changing in the shortgrass prairies of the United States. Historically, winter wheat – fallow has been the prevalent rotation, adjusting for low precipitation with fallow. Tillage was a key component of weed management during fallow. However, no-till systems have changed cropping systems such that producers now grow corn, sunflower, and proso millet along with winter wheat and fallow. These new rotations have doubled land productivity and net returns. Weed management also has changed. Producers now can manage weeds with an ecologically-based approach. With crop diversity and no-till systems, producers use cultural strategies that disrupt weed population dynamics, thereby reducing weed community density in crop land. Cost for weed management with the ecological approach is 50% less compared with previous crop production systems.
Technical Abstract: No-till systems have enabled producers to change crop production practices in the semiarid Central Great Plains of the United States. Previously, winter wheat (Triticum aestivum)-fallow was the prevalent rotation; now producers can 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 practices and long-term planning, has enabled producers to not only control weeds, but also reduce herbicide input and cost of weed management 50%. This paper explains the cultural strategies and ecological reasoning that led to this successful approach with weed management; our goal is to encourage producers and scientists in other semiarid regions to widen their perspective in considering components of weed management. In the Central Great Plains, the ecological approach emphasizes 3 goals: enhancing natural loss of weed seeds in soil, reducing weed seedling establishment, and minimizing seed production by established plants. Management systems involve cultural strategies related to rotation design, crop diversity within life-cycle intervals, no-till, crop residue management, and competitive canopies. Effectiveness with 1 component on weed dynamics influences impact of other components on weed management. Because this systems approach is so effective, innovative producers now view weed management in no-till cropping systems as a minor issue.