While we were in Japan in May, my partner and I helped Wakako and Masanori (chapters 7 and 11) make and eat a delicious seaweed condiment pickle of kombu and "sansho" a kind of wild prickly tasting peppercorn. We harvested wheat with Yamashita (chapter 9) in Kochi Prefecture in the south of Japan, looked through 400 year old medical books (printed on rice paper, and bought for pennies) with Oizumi (chapter 1) and planted rice with Murata as well as with the Oes. I wrote a lot about "Nature Farming" (no cultivation) in the book, but it wasn't until standing in the mud of the Oes' rice paddies and seeing how many living creatures teemed in that water that I 'got' it.
We then read the text in the book, it said that this plant was the basis of a war of sorts between the Wylackie and Yuki tribes, which are very small tribes, or were, that inhabited the area of what is now southern Trinity county and northern Mendocino county (a VERY specific area of California, and exactly where our land is). Seems they would burn this plant and use the ash as source of badly needed salt. Then we look up from the book and we're in a farmhouse in southern Japan's Shikoku island and Gufu's telling us about all the ways to cook with it, and what it can be used for medicinally.
Resolved: learn about the plants near us, and attempt foraging for more of our edibles when we get back.