I have been very thankful to have been able to talk to one of the worlds finest minds in the world of ethnobotony Professor, Kelly Kindsher. If you would like to read ANY study out there jto learn about this beautiful root, THIS is the one to read!
Thank you very much Professor!
Kindscher, K., J. Yang, Q. Long, R. Craft, and H. Loring. 2013. Harvest Sustainability Study of Wild Populations of Oshá, Ligusticum porteri. Open-File Report No. 176. Kansas Biological Survey. Lawrence, KS., 20 pp. [PDF file]