Where can I buy yarrow, a divination thing used in the Book of Changes?

Yarrow is a perennial herb of Compositae. Commonly known as calamus and saw grass. Few people use it today. Use bamboo sticks instead. Because the operation of "four camps become one change, 31% hexagrams, 18% hexagrams" is tedious and time-consuming, after the Tang Dynasty, most of them used hexagrams, that is, six hexagrams prediction method. You can also use Go, pebbles or playing cards instead. It is better to circulate coins with a plum blossom pattern of fifty cents, which is both simple and convincing. {Personal opinion, for reference only. Sister, I want to study & gt. I hope to find it. Thanks in advance. Dizzy, Zhouyi focuses on the principle of change and has no strict requirements on form. You don't need that kind of grass, because it's convenient to check the original post when marching in ancient times >>