As always, RedHawk, I appreciate the threads you start. Thanks for this one about soil vs dirt!
Hans, I also appreciate the answers you give in the threads I read here on permies. I was interested in having a plant source rich in silica and so internet-searched your suggestion of Horsetail rush. What I discovered was while it definitely is a good silica source, it had some potential toxin problems, including nicotine and thiaminase, see Plants for a Future at PFAF
and also check the work of herbal formulator James Sloane regarding Horsetail Grass. A couple of my medical conditions precluded using Horsetail rush for me.
While Horsetail rush will be a plant I put on my wish list as a fiber plant (scouring pans, etc.); silica-rich edible bamboo shoots could also be a potential choice for eating...although, according to guaduabamboo.com
, bamboo has heavy-duty toxins as well. Even when boiled, apparently pregnant women should not eat bamboo shoots, see Homeremedieslog.com
Obviously, I am no expert on any of these plants, but I thought you and others might appreciate what an internet search came up with. And, of course, each of us has a unique body with differing levels of tolerance to the foods we ingest...figure out what is best for you before you bite.