these mushrooms grow on black locust all my area too! they are a phellinus species. used by different first nations people as an ideal source of timber, they can hold embers for a long ass time. i feel like i've read a bit about their use as a medicinal incense also by first nations people, and about their ash being mixed with tobacco as a kind of snuff. since they're a polypore, the living white part on the underneath of the mushroom likely has some medicinal compounds but i don't think that's been studied too much. you could check this video if you wanna see someone using a similar polypore as a prehistoric lighter lol
i always thought they gotta be pretty powerful cuz they rot something nothing else can. haven't played around with it too much but i've seen springtails (tiny soil critters) eating em out in the deep woods during the snow melt so i always kind of played with the idea that they might be a really nice soil builder. if the underside has turned brown or black the mushroom's dead and i wouldn't feel too bad about burning it or composting it if that strikes your fancy. if it's white on the underside it's still living and sending out spores so i personally would let it do its thing!
as far as not eating something growing out of black locust, i've heard that too but paul stamets mentions growing reishi out of black locust and says nothing about that so idk?
Don't know what their called but I know you can use them for wood burning my dad is an artist he used to use those all the time I will find out how he harvested and cured them and post it on a thread if anyone is interested
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