04 Mar Alfalfa Weed Management
Conventional Alfalfa Establishment Offers Herbicide Rotation Opportunities to Hold Glyphosate-Resistant Weeds in Check- Alfalfa Weed Management Practices
Herbicide rotation is a widely accepted and essential management practice for reducing glyphosate-resistant weeds . A herbicide rotation plan can be your best defense against the onset and proliferation of glyphosate-resistant weeds in your fields. Rotate herbicide classes in order to control glyphosate-resistant weeds that are already present on your farm — better yet, delay or prevent their onset and proliferation in your fields.
Many weed species have developed glyphosate resistance to the point where glyphosate-resistant weeds predominate in many fields. Despite the prevalence of glyphosate-resistant weed variants, glyphosate can have a place in your row crop production plan. Conventional alfalfa in your alfalfa weed management rotation provides an opportunity to slow or prevent the onset of herbicide resistant weeds via herbicide rotation. Alfalfa offers an excellent opportunity to rotate herbicide classes or groups, using herbicides from different herbicide groups than you typically use to control weeds in row crops.
The Roundup Ready® trait is priced much higher in alfalfa than it is priced in corn or soybeans. It can make financial sense to maintain glyphosate use in crops where it is least expensive within your herbicide rotation plan, and in crops where additional trait options give you the option to control some of the most prevalent glyphosate-resistant weed species.
For best establishment of conventional alfalfa, apply a broad spectrum pre-plant or pre-emerge herbicide according to label directions, and plant seed into a firm seedbed 1/4″ to 1/2″ inch deep.
For more information on alfalfa establishment options visit…..
https://www.midwestforage.org/non-researchpdf/291.pdf
The Weed Science Society of America maintains a listing of herbicide chemical names, and groups them by SOA codes. SOA stands for site of action and refers to the biosynthesis pathways affected by each SOA group. In some publications these codes may also be referenced as herbicide mode of action or MOA groups. Glyphosate stands alone in SOA Group 9. Thus any other herbicide that is labeled for your crop has the potential to be part of your herbicide rotation plan for weed species listed on the herbicide label. You can learn more about the SOA Groups at these websites….
https://iwilltakeaction.com/uploads/files/2020-take-action-herbicide-classification-chart.pdf
https://wssa.net/wssa/weed/herbicides/
When establishing alfalfa, there are several SOA herbicide groups available as alternatives to glyphosate, with useful information shown in the table below.
Much more information can be found in the herbicide labels for each one. Always read and follow label directions when handling and applying all herbicides and pesticides.
