Fireweed gets its name because it returns quickly to burned areas. Chamaenerion is one of the newer names bestowed by the chromosome crunchers. You may find fireweed as Epilobium angustifolium in older books. Fireweed stems and leaves were eaten fresh or cooked by Indians. The Dena'ina add it to dogfood.
Who are the Dena'ina? That bit of curiosity led to this wonderful bit of language at www.eklutnainc.com/culture. "The Dena'ina are an early indiginous population of the Knik Arm area. Anchorage lies within Dena'ina Elnina and is home to the K'enaht'ana, the indigenous people of Nuti(Knik Arm), who today are members of the Eklutna(Eydlughet) and Knik(K'enakatnu) tribes." I suspect their language is a lot like Shakespeare - it flows much better when heard than when read, and fascinating in any case.