Question from TA
Hi Debra,
Recently a yard worker sprayed something for weeds on my back patio. It turns out it was Round-up.
Any suggestions for mitigating damage, or is it just “what’s done is done”? It was a couple of weeks ago, so I suspect there’s really nothing to do about it now.
Debra’s Answer
Whenever any type of herbicide or pesticide is sprayed, the first thing to do is look up the “half-life,” which is the time required for half of the compound to dissipate or degrade.
Monsanto says the half-life of glyphosate varies, depending on conditions, which is true, ranging from as short as 2 days up to 141 days, with an average half-life of 32 days.
More interesting is the Environmental Fate of Glyphosate, published by the California Department of Pesticide Regulation. It describes how glyphosate can float through the air and damage plants outside of the zone where it was applied and is easily absorbed by soil.
In the soil environment, glyphosate is “resistant to chemical degradation, is stable to sunlight, is relatively nonleachables, and has a low tendency to runoff.” Yikes. It’s going to stay there a while.
I’ve had success in the past calling pesticide manufacturers and asking for the “cleanup” chemical that breaks down the pesticide. There might be one you can clean up with.
