Pleurotus citrinopileatus, an invasive fungus escaping from cultivation
The golden oyster mushroom Pleurotus citrinopileatus is a wood decay fungus which is grown in cultivation as an edible species, both by professionals and amateurs. It is native in the Russian Far East and East Asia. It was first recorded in the USA in 2012 where it now occurs in 25 states and records exists in several EPPO countries.
A risk assessment was conducted by the GB Non-native Species Secretariat in the United Kingdom after P. citrinopileatus was found in two locations (Liverpool, North West England region) and Barnsley (Yorkshire and the Humber region). They conclude that the likelihood of entry and establishment in the United Kingdom is very likely, and the spread would be very rapid. Although direct economic impact is expected to be minor, environmental impact is assessed as major, as P. citrinopileatus is expected to outcompete native saprotrophic fungi, as observed in the USA.
A recent article by Stallman & Allen (2026) underlines the risk associated with the intentional import of invasive fungi that are cultivated for food or medicinal uses. They recommend that the sale of known invasive species such as P. citrinopileatus should be banned in areas where they are not established, and that instructions are provided to dispose safely of commercial grow-at-home kits.
Sources
GB Non-native Species Rapid Risk Assessment for Pleurotus citrinopileatus (Singer) (golden oyster mushroom). https://www.nonnativespecies.org/assets/Uploads/Pleurotus-citrinopileatus-RRA-final.pdf
Stallman JK, Allen JL (2026) What should we do about cultivated mushroom invasions? Studies in Fungi 11, e010 https://doi.org/10.48130/sif-0026-0008