Ask Mr. Smarty Plants

This just proves that a plant does not have to be non-native to be invasive. This USDA Plant Profile Map shows that while Stachys floridana (Florida hedgenettle) is not native to Horry County, it does grow near there and has obviously invaded your property.

Because we are not familiar with this plant, we found this article from North Carolina State University Cooperative Extension on Florida betony. We learned from this that a spray cannot easily access the tubers in the ground, but can certainly kill things around it that you didn't want killed. One technique that we have sometimes recommended involves clipping the stem of the offending plant down near the surface of the soil. Using a disposable sponge paint brush, quickly drench the cut surface of that stem. With good luck this will penetrate down to the tuber without the stem having time to heal over to protect the tuber. Beyond that, sheer perserverance is about your only resort.

From this Dave's Garden forum, you will learn that it is also edible, in case you need a backup food supply.

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