JoAnne Skelly
I recently read that the formulation of a leading residential use herbicide had changed in late 2022. Roundup, a Bayer product, has been a mainstay for many American gardeners.
The active ingredient was glyphosate, which has now been replaced with “fluazifop-p-butyl, triclopyr TEA salt, diquat dibromide and imazapic ammonium (bayer.com/en/roundup-ingredient-safety).
Glyphosate containing products are no longer produced or sold by Bayer for home use, although some quantities may still be on store shelves.
According to Bayer, all new lawn and garden products have been “thoroughly studied, reviewed and approved by independent experts at the Environmental Protection Agency” and can be used safely following “the approved label instructions.”
Bayer states they changed the chemicals not because of safety concerns with glyphosate, but to manage litigation risk from residential lawn and garden users.
Glyphosate has a controversial history, and some countries, states and communities have banned it. It is still an active ingredient in many agriculture and professional products.
In the past, I often cautioned gardeners about using the non-selective glyphosate products because they did not discriminate in what plants they damaged or killed.
Unfortunately, many people did not understand what non-selective meant. They often applied these products to kill lawn weeds without realizing they would also kill the grass they were trying to beautify.
I was familiar with fluazifop-p-butyl as a selective herbicide to kill grasses, both annual and perennial. I wasn’t very familiar with triclopyr, a selective systemic (absorbed through the tissue of the plant and spread throughout its structure) herbicide that targets woody and herbaceous plants.
Diquat dibromide is a non-selective herbicide that desiccates and defoliates whatever it touches on contact. When I looked at labels for active ingredients in non-selective herbicides online, I found that some have similar ingredients to those in the new Roundup, while some still contained glyphosate.
I think the most important thing to remember is that if you use herbicides (weed killers), be sure you read the entire label thoroughly.
It will tell you: what safety equipment should be worn; what weeds the product will control; what plants it shouldn’t be applied on or near; where in the yard it should and shouldn’t be used; what the ingredients are; how it will affect humans, pets, aquatic organisms, birds, mammals, etc.; what to do in case of a spill or exposure; how to dispose of it safely and properly; and much more information.
If you choose to apply herbicides, be smart and read the label before purchase and use.
JoAnne Skelly is Associate Professor & Extension Educator Emerita University of Nevada Cooperative Extension. Email skellyj@unr.edu.