The golden oyster mushroom (Pleurotus citrinopileatus), originally cultivated in Asia, has escaped into North American forests and is now found in 25 U.S. states and one Canadian province. This fast-spreading, commercially sold species is disrupting native fungal ecosystems: trees colonized by golden oysters show reduced fungal diversity and altered microbial communities. Researchers warn that climate change could accelerate its spread, making golden oysters a pressing ecological threat. We’ve also written about this before in-depth.