It's easy to believe that a mix of white vinegar, salt, and dishwasher liquid soap is somehow different from a nasty chemical-y weedkiller.
But, as comedian and writer Glen Tickle's Twitter joke, seen above, makes plain: everything we use is made of chemicals. They are an inescapable fact of modern life.
And that's OK!
When Andrew Kniss, a Wyoming weed (not that kind) scientist, ran an analysis on the ingredients in this homemade weed killer, he found that it was more toxic than glyphosate, aka Roundup, aka Monsanto's Roundup.
In a standard laboratory test, called the LD50, the "acetic acid is more toxic than glyphosate." And because of the mix of chemicals in the recipe and the amount of weedkiller one would apply, "the acetic acid in the homemade mixture is nearly 10 times more lethal than the glyphosate in the Eliminate [a Roundup product] mixture." Oh, and the homemade weedkiller would stick around in the soil longer.
But the truth is: Both of them are OK to use, if used properly with standard safety practices.
And if you're really worried about weeds—and not about making a certain point about the danger of chemicals—Kniss also has a breakdown of when you might want to use a contact herbicide like the acetic acid mix and when you might want a systemic herbicide like glyphosate.
So, keep all this in mind the next time someone tells you to use a "homemade" weed or bug killer. There may be good reasons to do so, but the idea of the "natural" that they rely on is a fiction.
We want to hear what you think about this article. Submit a letter to the editor or write to firstname.lastname@example.org.