{"id":4061,"date":"2019-04-30T00:00:00","date_gmt":"2019-04-30T04:00:00","guid":{"rendered":"https:\/\/firstascentstaging.com\/iwm2019\/chemical-practices\/"},"modified":"2025-05-20T08:27:15","modified_gmt":"2025-05-20T12:27:15","slug":"herbicide-control","status":"publish","type":"page","link":"https:\/\/growiwm.org\/herbicide-control\/","title":{"rendered":"Herbicides and Resistance Management"},"content":{"rendered":"\n
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Herbicides and Resistance Management<\/h1>\n\t\t\t
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Many state Extension programs publish current herbicide use recommendations for effective weed control and are an excellent source of unbiased information. This often begins with selecting herbicides that control the target weed(s) and applying them at the correct rate and time.  For resistance management, this expands to include guidelines for using herbicide mixtures and rotating herbicide modes of action (MOA) as part of an effective integrated weed management program.  This page is designed to discuss the principles behind herbicide selection to help mitigate herbicide resistance and to be complementary to state recommendations (see citations section at the end). information exists about herbicide options for herbicide intensive weed control. Many state extension programs publish current recommendations for effective control and are an excellent source of unbiased information. This page is designed to discuss the principles behind herbicide selection and to be complementary to state recommendations.<\/p>\n<\/div><\/div>

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Selecting Effective Herbicide Options in a Resistance Management Program<\/span><\/h4>\n<\/div><\/div>
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Herbicide Group Numbers are found on herbicide labels and listed in educational materials to help users understand how herbicides control weeds (Fig. 1<\/em>). These herbicide group numbers correspond with individual herbicide modes of action<\/strong>.  The MOA describes the way a herbicide works to control weeds. The numerical MOA system groups herbicides and provides a reference for growers and ag professionals to help implement herbicide programs that mitigate resistance.<\/p>\n<\/div><\/div>

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In contrast, the herbicide site of action<\/strong>, or target site, is the location of the primary interruption\/disruption and is often a specific plant enzyme.  In most cases, herbicides within the same MOA group have the same site of action (see The Basics of Herbicide Resistance<\/a> for more details). 
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Effective herbicide-resistance management must include rotating herbicide MOA, using multiple, effective MOA in mixture, and treating fewer weeds with herbicides by integrating multiple effective management strategies that lessen the impacts of weeds and reduce weed seed production.<\/p>\n<\/div><\/div>

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Here is a list of herbicide management considerations to help delay and manage herbicide resistance.
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