In your survival quest have you tried the libraries? The pre europeans had to live without modern things, they knew which plant was for what job. Have your libraries got any books from that period where the ancient tales are told? "Op Shops" [opertunity] here have all sorts of old book, your may be the same
There may be a bit of trouble identifuing old names to your plants but it should be do able. Don't forget, grated fern root I presume you havr fern root there.dried then mixed with water into a dough, shaped into a ball, placed in the embers. Scrape the outer layer off and eat the rest.