Well, there are mushrooms and mushrooms. The common commercial white and brown button/portobello mushrooms (Agaricus campestris and Agaricus bisporus) are pret

Well, there are mushrooms and mushrooms. The common commercial white and brown button/portobello mushrooms (Agaricus campestris and Agaricus bisporus) are pretty easy to grow -- they've been cultivated at scale since the 1700s. Others (such as oyster mushrooms and shiitake) aren't too much harder. Unfortunately, the most prized species (truffles, morels) are more tricky. Commercial truffle cultivation does exist, but it's a roll of the dice. You inoculate your trees, then you pray. It's nothing like the large-scale factory model used for the Agaricus species. With respect to morels, while several people over the years have claimed to have a process for cultivating them, no one (to my knowledge) has ever been successful at producing them on a commercial scale. Virtually all morels are still harvested in the wild. That's a real pity, because they are worlds better than the Agaricus species.