You may be familiar with the plant genus Equisetum, more commonly known as horsetail or scouring rush. Scouring rush is a practical name based on where Equisetum is found and what it’s good for. Rushes generally grow in water and Equisetum, while not exactly a type of rush, certainly won’t be found far from a stream. And this plant was used for scrubbing pots before the invention of that rough green stuff on all the sponges you buy now. It’s so effective at pot-scrubbing because its cell walls contain silica.
This study tries to explain how the heck silica gets from hanging out in dirt to being a component of cell walls. It’s not that simple. Remember when you were a kid and ate dirt? You didn’t suddenly develop skin like sandpaper. Conclusion: Equisetum is cooler than kids.
Some people say you should make tea with it for hypothyroidism or try eating it if it’s a problem in your garden. I would really only suggest ingesting it if you feel that hypothyroidism or weeds in your garden make life not worth living as it’s toxic enough to kill a cow through disruption of thiamine metabolism.