Milfoil
It sounds like a regional shamanic tradition. Shamanism is not just American - they just get the publicity.
Shamanism isn't American either (sorry, not meaning to be rude) and most 1st Nation Americans don't recognise the word, their medicine people often don't work in altered states of consciousness. The word comes from the Tuvan language of the Tungus district in Siberia. Shamanism involves altered states of consciousness by which the Ancestors and other Spirits are contacted.
What is being described here sounds much more like a regionally specific, nature based belief system with some similarities to Balkan witchcraft and some HooDoo.
It also reminds me of a film I saw a while back about an American family of women who passed on their 'craft' only to their daughters and whatever element they resonated with. The daughter was also an Earth person, making massive sculptures!
The beautiful thing though is that all over the world we have survivals of the old beliefs which meander like streams, adapting to their particular locale and synchronising with other, similar systems.