Title: Biological aspects of weed dynamics in no-till systems Author
Submitted to: Grain
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 1, 2014
Publication Date: May 1, 2014
Citation: Anderson, R.L. 2014. Biological aspects of weed dynamics in no-till systems. Grain. 75:313-320. Interpretive Summary: Weed management in the early years of no-till was often ineffective. As we have gained knowledge about no-till impacts on weed dynamics, we have been able to develop no-till cropping systems that effectively manage weeds. No-till helps weed management because weed seeds do not survive as long lying on the soil surface compared with burial in soil. However, it is necessary to use rotations that include crops with a diversity of life cycles to gain the benefit of no-till on weed dynamics. Producers are controlling weeds in no-till systems with 50% less costs compared to conventional systems with less crop diversity. No-till systems are helping producers restore soil health as well as improve their economic returns.
Technical Abstract: Scientists and producers in the Eurasian steppe are interested in no-till crop production, but are concerned that, without tillage, weed density will escalate in croplands. In the United States, producers have used no-till systems for several decades and weed density has not increased. In this paper, we review how no-till affects biological processes of weed dynamics and describe no-till cropping systems in the U.S. where weeds are successfully managed. No-till helps weed management because weed seeds do not survive as long lying on the soil surface compared with burial in soil. However, it is necessary to use rotations that include crops with a diversity of life cycles to gain the benefit of no-till on weed dynamics. Integrating no-till with crop diversity has enabled producers in the semiarid steppe of the U.S. to manage weeds with 50% less cost compared to tilled rotations with less crop diversity. In contrast, weed management in no-till rotations with few crops rely on intensive use of herbicides, which is leading to resistant weeds. In some situations, resistant weeds have forced producers to return to tillage. No-till with diversified rotations accrue numerous benefits for North American producers, such as increasing net return and restoring soil health. Eurasian producers can gain similar benefits with no-till and still manage weeds effectively.