Although there are countries where magic mushrooms are entirely legal to grow, sell and consume, the United States is not one of them. As you enter the country with psilocybe cubensis mushrooms in your possession, you are liable to be arrested and prosecuted, even if the amount you carry is not that great.
Fortunately, not all products associated with magic mushrooms carry the same punishments, and some will not get you in trouble at all. For instance, having mushroom spore syringes on you will likely not lead to any legal problems, since mushroom spores don’t contain any psilocybin. The substance only appears once the mushrooms start to grow.
You can purchase bulk mushroom spores to grow psilocybe cubensis mushrooms. This presents a legal gray area because of spores lack psilocybin. As a result, you can buy and sell spores without much of an issue, and their use in scientific research is generally unrestricted. However, keep in mind that this isn’t the same everywhere. Psilocybe mushroom spores are decriminalized in all states except for three: California, Georgia and Idaho.
Even in other states, it’s important to note that the spores can only be sold or bought for educational and research purposes. Sellers will caution against using them to grow hallucinogenic mushrooms, and the punishment for being caught using them can vary greatly depending on each jurisdiction.