In the United States, diquat is used everywhere—from the potato fields of the Pacific Northwest to the watersheds of New England and the weeds wilting along suburban sidewalks. Approved by the Environmental Protection Agency (EPA), this fast-acting herbicide remains a go-to chemical for farmers and home gardeners. A growing body of scientific research, however, has highlighted the harmful effects resulting from its widespread use.
If you can find it, ‘wood vinegar’ works as an herbicide at higher concentrations, but then supposedly dilutes throughout the soil/with rain to a level which is a type of soil amendment.
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