J.Quondam
CR 1/8
I'll second this. It's a fantastic resource largely based on real-world folklore, iirc. Plus it's just a beautiful book, as well.I actually own a book about this called the Herbalist’s Primer. I got it from kickstarter a year or two ago. It covers tons of plants, giving them descriptions, medicinal properties, magical properties, how to get them, and more.
The author has done/is doing a couple others in the same vein other different topics, for example one about minerals.