When I was maybe 21 I started this interest in what could be done with the plants that grow around us… what’s edible, what’s medicinal, what’s useful in other ways. I dyed up some yarn I got at some fair with black walnuts and at least one or two other things, and even though I hardly knew how to knit, I made an Andean style hat with llamas and earflaps. In my memory it came out pretty well, but it’s long gone, along with the man I gave it to (actually I left him, and the hat ended up with a daughter of a friend out west).
I had quit mechanical engineering school and was drifting around odd jobs in Syracuse, when one day I wandered through Illick Hall on my way to a bookstore job. There was a display in the lobby of lichens and mosses. I had been reading about lichens as dye plants and was amused at the idea of setting them in a bucket of stale urine in the sun to get some amazing colors.
So I hunted down the professor. I found out he taught a bryoecology class (ecology of bryophytes, an upper level class) and it was starting soon and I wanted in. He asked if I had any college level biology coursework, I said no. He told me the class was mosses and liverworts not lichens, I said I didn’t care I still wanted to take it. He was reluctant to let me in, but he did. And I got an A. And that fall I was enrolled full time as a plant ecology student to finish up my BS. I credit him much with that decision. He was a great professor, a natural teacher, who shared his enthusiasms and interests.
Anyhow, you’ll note my recent, um, obsession with fungi and dyeing. Look what came to me recently,

A lichen called rock tripe (lichens are a symbiosis of fungi and blue green algae)
Um, yeah, you can eat the stuff, but I imagine it’s little better than shoe leather.
Anyhow, I’ve been making use of interlibrary loan,

and Casselman says that stale urine is little more offensive than ammonia. I think collecting it will be a weekend activity.
I only browsed the book a bit, but it looks really informative. And potentially entertaining. She has a “how to identify” section for all the plants. Here’s the one for beets: “look at the supermarket for a red, bulbous-shaped, tuberous vegetable with large green and red-veined leaves“. Or you could just look for the sign or tag.