salts kill mushrooms, unfortunately they also kill plants. Some mushroom farms use peroxide to sterilize seasoned wood or straw surfaces so it should take down the mycelium...apply diluted 3% peroxide once a week to everything and they will stop showing up. But then the problem is what comes next to eat the dead mycelium??? probably mold or something else that could rot your plants. or you can just keep applying diluted peroxide...
The only psychoactive mushrooms I'm aware of that will grow on wood are Amanita muscaria, and they're not to be considered in the same class as Psilocybe or Panaeolus mushrooms. The difference between a "therapeutic" dose of Amanita and a lethal one is a bit close for my comfort level. You likely couldn't hold a lethal dose of Psilocybes or Panaeolus down long enough to actually metabolize it. Be careful out there!