Dear Umbra,

I have a large, organic (hopefully) vegetable garden. However, I occasionally use Roundup around the edges to keep invasive grasses from creeping in. Now, I have been given to understand that Roundup is relatively safe and breaks down almost immediately. What are your thoughts on this subject? I totally trust your judgment.


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Dearest Betsy,

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Roundup is relatively safe — it’s not as bad as, say, depleted uranium — but that doesn’t mean you want to go pouring it on your pancakes. I’m more than happy to give you the information you seek regarding its toxicity; however, as I mentioned above, it’s your own judgment that should be the priority, not mine. Here are my thoughts, numbered in Finnish.

Yksi (1): Roundup is manufactured by Monsanto, a company responsible for transforming the face of agriculture through genetically engineered seed. Monsanto, which has become something of a poster child for coldhearted corporate evil, developed (and patented) seeds resistant to Roundup so that farmers could apply the herbicide to their fields willy-nilly with no fear of killing mature crops. The majority of soy grown worldwide is now genetically modified, despite a poor understanding of the possible long-term implications. Genetic drift is putting organic farmers out of business, traditional seed stocks are dying out, and meanwhile Roundup sales have risen and Monsanto is suing farmers for patent infringement — including farmers who never bought the “Roundup Ready” seeds but whose fields were infected through pollen drift.

Kaksi (2): If you are applying chemical pesticides or herbicides on your garden, it is not an organic garden. Regular use of chemicals to solve a garden problem indicates a larger problem with the design of your landscape. Chemicals should be a last and infrequent resort.

Kolme (3): Roundup is in Toxicity Category III (Caution); the categories are established by the U.S. EPA via tests on rats. You can learn more than you would ever like to know about what this means by reading a lovely article from the Journal of Pesticide Reform, but I’ll briefly cover some of the highlights here.

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Roundup’s active ingredient is glyphosate, which is also available in other fine Monsanto products such as Rodeo and Accord. Also contained in that little bottle of death are “inert” ingredients such as surfactants, which help the active ingredient penetrate the cells of its victims and are often comparably toxic. Glyphosate is the most popular pesticide in the U.S., partially due to the persistent rumor that it is benign. My own brother insisted that it was safe enough to drink. Obviously, Monsanto is benefiting from such rumors, and in fact has been sued for promulgating them.

Glyphosate and/or Roundup are harmful to aquatic insects, have widely varying half-lives in soil, and have been associated with damage to the nervous system, reproductive system, respiratory system, and skin. Your Roundup usage is probably endangering your health and damaging your garden crops. Although Roundup will most likely bind to the soil particles where it is applied and stay there for months or years, it can also migrate from those particles to adjacent soil or water, where it will damage seeds, worms, ladybugs, etc. Depending on your method of application, it may await you in your salad. In Monsanto’s own tests, Roundup was found on lettuce five months after it was applied. Not the most healthful salad dressing — although it may be fat-free.

Fortunately, Roundup is not the only or best response to invasive grass. It’s possible that a simply physical barrier, such as a plank, would stop the march of weeds. Space does not permit a discussion of your specific garden problem, but if you consult a few sources on organic gardening (try your local nursery or gardening magazines), I’m sure you can find suggestions for grass determent that will never leave you wondering about your health.