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Roundup products available on the homeowner market no longer contain glyphosate. Homeowner/consumer herbicides are marketed primarily for noncommercial applicators for control of weeds in gardens, lawns and ornamental plantings. They do not require a pesticide applicator’s license to purchase and use, unlike restricted use pesticides. Consumer pesticides also typically have a much lower active ingredient percentage compared to their restricted use counterparts. For several decades, the herbicide trade name Roundup has been synonymous with the active ingredient glyphosate. While this is still largely true for the commercial market, including products such as Roundup PowerMAX 3, this is no longer the case for the homeowner/consumer market. Glyphosate is the active ingredient used widely for its systemic, nonselective control of many weed species in a variety of residential and agricultural crops. It is commonly used for burn-down or targeted applications, in which the applicator wants to kill emerged weeds. For residential use, glyphosate has commonly been used to control weeds ahead of garden planting or to spot treat weeds in landscape plantings, lawns and along sidewalks and fencerows. Part of what makes glyphosate an effective herbicide for this purpose is its nonselective activity on most plant species and its lack of soil residual activity. This means that glyphosate is typically only injurious on plants that it contacts via direct spray or spray drift.
Recently, Roundup products available on the homeowner market have had their active ingredients changed from glyphosate to a mixture of several herbicides. However, these herbicides have different modes of action from glyphosate and may cause unexpected results for homeowners who are not aware of the change. One such product, Roundup Weed & Grass Killer, contains triclopyr, fluazifop and diquat (Image 1). The combination of these three active ingredients results in a product that can deliver similar nonselective control to that provided by glyphosate; however, the symptomology of these herbicides is very different from glyphosate. While glyphosate causes yellowing and plant tissue death over a couple of weeks following application, the combination of these active ingredients can cause leaf and steam twisting, yellowing and purpling, death of the growing point in grasses and rapid tissue death. Furthermore, these herbicides may show activity more rapidly than products containing only glyphosate. Off-target drift or accidental sprays with this product will cause very different injury compared to glyphosate, and many desirable ornamental species may exhibit different levels of sensitivity to these chemicals than they do to glyphosate.
Image 1. Manufacturer’s product label of Roundup Weed & Grass Killer as of July 2025. Photo by Colton D. Blankenship
Image 2. Manufacturer’s product label of Roundup Dual Action Weed & Grass Killer Plus 4 Month Preventer as of July 2025. Photo by Colton D. Blankenship
Another example is Roundup Dual Action Weed & Grass Killer Plus 4 Month Preventer, which contains triclopyr, fluazifop, diquat and imazapic (Image 2). Imazapic is an herbicide which is commonly used for both preemergence and postemergence control of weeds. This is important, as the soil residual activity of imazapic is a notable difference from the lack of soil residual activity from glyphosate. Using this product for burndown prior to planting a garden or landscape plants, for example, will almost certainly result in extreme plant injury up to and including plant death for many species. Additionally, using this product near sensitive ornamental species may also result in plant injury via drift or herbicide uptake. Other Roundup products may contain different combinations of active ingredients designed to target specific weed species. This information is outlined on the label available on every product container. These examples highlight the responsibility of the applicator to review the product label before making any pesticide application; even if a product seems familiar, applicators must refer to the label to ensure no information has changed, even including the active ingredients and use patterns.
If you still possess any products with the old formulation, they can still be used according to the instructions on the product label. While consumer Roundup products are no longer being produced with glyphosate, retailers may still sell products with the original formulation purchased prior to the formulation change. Always review the product label before purchasing a pesticide to ensure that the use pattern and restrictions align with your needs.
Use caution when using herbicide products near desirable garden plants, turfgrasses and landscape ornamentals. Ensure that all applications are made in a manner consistent with the labeled instructions. Do not assume that these new products will behave in the same manner as previously available products containing glyphosate. While the formulations have changed, consumer Roundup products can still be effective weed control tools when used according to labeled instructions.
This article is meant to be informative and is not an endorsement for or against any product.
For more information on herbicides, please contact your local LSU AgCenter Extension office or visit www.LSUAgCenter.com
Colton D. Blankenship, Assistant Professor and Extension Specialist, Hammond Research Station
P4011
08/27/2025
The LSU AgCenter and LSU provide equal opportunities in programs and employment.
