Dispelling Common Misconceptions about Superweeds (fact sheet) — Weed Science Society of America Press Release 10/8/2014 International survey of herbicide-resistant weeds www.weedscience.org Farmers Battle Herbicide Resistance with Harvest-Time Weed Seed Controls — Weed Science Society of America Press Release Nov. 5, 2014 Resistance by the Numbers — PowerPoint presentation by John Stone, Michigan State University. 2015. The following […]
Herbicide Resistance
Mechanisms of Herbicide Resistance
What occurs within a resistant plant that allows it to survive after an herbicide application? What characteristics do the resistant plants possess that the susceptible plants lack? The four known mechanisms of resistance to herbicides are: Altered target site: An herbicide has a specific site (target site of action) where it acts to disrupt a […]
Incidence and History of Herbicide Resistance
The first reported case of herbicide resistance in the United States was reported in the 1950s. Field bindweed resistance to 2,4-D was reported in Kansas in 1964, and common groundsel resistance to triazine herbicides was discovered in Washington in 1970. Beginning in the 1980s, the number of reported resistant biotypes began increasing rapidly in the […]
Is Herbicide Resistance to Blame?
Weed control failures Most weed control failures are not due to resistance. Before assuming weeds surviving an herbicide application are resistant, eliminate other possible causes of poor control: Herbicide application Inadequate rate Poor spray coverage and/or incorporation Improper timing of application of postemergence herbicides (after weeds are too large to control) Failure to use an […]
Herbicide Resistance
Herbicide resistance is the inherited ability of a biotype of a weed to survive an herbicide application to which the original population was susceptible. A biotype is a group of plants within a species that has biological traits (such as resistance to a particular herbicide) not common to the population as a whole. In simple […]