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Weed Succession under Conservation Tillage: A Hierarchical Framework for Research and Management

Published online by Cambridge University Press:  12 June 2017

Clarence J. Swanton ,
David R. Clements  and
Douglas A. Derksen
Clarence J. Swanton
Affiliation:
Dep. Crop Sci., Univ. Guelph, Guelph, ON N1G 2W1, Canada
David R. Clements
Affiliation:
Dep. Crop Sci., Univ. Guelph, Guelph, ON N1G 2W1, Canada
Douglas A. Derksen
Affiliation:
Agriculture Canada, Indian Head, SK, S0G 2K0
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Abstract

The awareness and adoption of conservation tillage is one of the most important changes taking place in agriculture today. There are, however, concerns regarding weed species shifts under conservation tillage. Under conservation tillage, shifts toward grass, perennial, wind-disseminated weeds and volunteer crop plants have been observed. Shifts in weed species composition may either represent long-term ecological succession or temporary fluctuations in species composition; few long-term studies have examined the ecology of these shifts in detail. Further studies are needed to identify mechanisms driving these shifts to determine whether they are fluctuational or successional and to develop more sophisticated management strategies. In this paper, we present a research approach for studying ecological processes such as competition within a hierarchical framework of all possible causes, processes, and defining factors related to weed succession under conservation tillage. Succession management strategies can be developed to act at the causal level in the successional hierarchy. Three primary causes are site availability, colonization, and species performance. Site availability may be controlled through “designed disturbance”, while differential species availability may be regulated through “controlled colonization” and species performance may be regulated through “controlled species performance”. In general, the goals of succession management would involve reducing populations of the weed species most likely to proliferate under conservation tillage. Comprehensive ecological research, within the hierarchical framework outlined here, would identify potential problems and enable management strategies to account for the numerous factors that may be influencing fluctuations and succession of weeds under conservation tillage.

Keywords

Ecologyweed shiftsweed managementno-tillresearch strategy
Type
Feature/Review
Information
Weed Technology , Volume 7 , Issue 2 , June 1993 , pp. 286 - 297
Copyright
Copyright © 1993 Weed Science Society of America 

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