Erechtites hieraciifolius
Erechtites hieraciifolius (L.) Raf. ex DC.
Engl.: fireweed, American burnweed, American fireweed, burnweed, Malayan groundsel, pilewort, true fireweed.
Deu.: Schein-Greiskraut.
Bot. syn.: Erechthites hieracifolia (L.) Raf. ex DC., Erechtites hieraciifolia (L.) Raf. ex DC., Senecio hieracifolius L., Senecio hieraciifolius L.
The Medical Flora of Kansas: Dioscorea - Gymnocladus.
Classic texts: Journals: TNEMA 1882-1883.
Epilobium.
Henriette's herbal blog: It's easy to pick great willowherb in quantity.