Q: These weeds have taken over my beds. Can you help? What should I use to kill?
A: The weed is yellow wood sorrel, Oxalis stricta, sometimes called yellow clover. It is tough to control. It arises from a taproot each year and scatters copious seeds during its blooming season.
In an empty bed, glyphosate (click for sources) or any broadleaf weed killer (click for sources) will kill the green top growth but the root will probably resprout. This means you have to apply the product multiple times until the oxalis is altogether dead.
If it is presently growing among flowers, dip a foam sponge in weed killer and brush the chemical onto the weed leaves.
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