I took a weekend seminar in herbology a few years back and we used this book, From The Sherpherd's Purse. It was a great seminar because we went on a nature walk and found some wild species from our book. The class was offered by a local community center. Not in depth but alot of fun!
Author, Max G. Barlow, DBM, Dr. of Botanical medicine, CL & Merchant at Law.
A botany perspective:
Purple Cone Flower (echinacea)
part used: root
time of collection Aug, Sept, Oct, time of day 9am-3pm