One of the most important medicinal herbs worldwide. Used historically for vast numbers of diseases and complaints by Native Americans. Now recognized as short-term immunostimulant, especially for diseases of respiratory tract, and topically for inflamed wounds, herpetic lesions, and abscesses. All plant parts contain the active ingredients, echinacosides, with the concentration being strongest in the roots. Other species contain them as well, but to slightly lesser degree.
Plains Native Americans are said to have used Echinacea for more medicinal purposes than any other plant group. Root (chewed, or in tea) used for snakebites, spider bites, cancers, toothaches, burns, hard-to-heal sores and wounds, colds and the flu. Science confirms many traditional uses, plus cortisone-like activity and insecticidal, bactericidal, and immunostimulant activities.
References:
Hostettmann, K. (2003). "Geschichte einer Pflanze am Beispiel von Echinacea" [History of a plant: the example of Echinacea]. Complementary Medicine Research (in German). 10 (1): 9–12. doi:10.1159/000071678
Kindscher, Kelly (2007). "Plant Lore". In Wishart, David J. (ed.). Encyclopedia of the Great Plains Indians. University of Nebraska Press. p. 166. ISBN 978-0-8032-9862-0.
Liu J, Yang L, Dong Y, Zhang B, Ma X. Echinacoside, an Inestimable Natural Product in Treatment of Neurological and other Disorders. Molecules. 2018 May 18;23(5):1213. doi: 10.3390/molecules23051213. PMID: 29783690; PMCID: PMC6100060.
Grieve, M. (Maud). A Modern Herbal; the Medicinal, Culinary, Cosmetic and Economic Properties, Cultivation and Folk-Lore of Herbs, Grasses, Fungi, Shrubs, & Trees with All Their Modern Scientific Uses. New York :Harcourt, Brace & company, 1931.
Image attribution: Ernie - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=7453562