Who among us hasnt cleaned our camp pots with some local variety of Scouring-Rush, also know as Horsetail? Widely abundant in wet areas, Equisetum hyemale incorporates silica (among other abrasive minerals, such as goldprospectors used to eyeball this plant for the tell-tale signs of a motherlode) within its tissues. Perhaps this thwarts herbivores from consuming it. Young, peeled shoots are edible to humans, though...
I want to share with you some simple sanders and grinders one can make with natural resources.
While I was exploring the Baking-Hot-Pit-of-Mojave-Desert-Death, I stumbled across some fine black sand. It proved to be almost as abrasive as red garnet-rich sand that Jeff Gottlieb sent me from New York. Under a microscope, one can see wondrous gems that cover nearly the whole spectrum of rainbow colors!
I applied this black sand to a rock using deer hide glue! Use as one would sandpaper...
Equisetum hyemale (Horsetail). The top length sports a fertile, spore-bearing tip. You can also see the white, reduced leaves (a result of evolutionary processes) and the black internodes. Much like bamboo, under the black lines lay a wall that divides the inner stem into segments.
To create an abrasive horsetail patch: cut within the internodes; flatten the rolled-up segments with your fingers; press between two flat rocks; wait a few days until dry.
Effectiveness on wood...