I'm a total noob, so I don't wanna pretend to have much by way of real answers. Just kinda giving my basic understanding, which could easily be wrong. Under the right conditions, sure, they'll grow on shit in the wild. But considering the sheer number of spores floating around and the fairly sparse wild shroom populations you're likely to actually run across, it's not exactly a very high percentage of spores successfully getting to the point where they produce fruit.
It's really not much of a pain in the nuts to do. The cleaner the general environment, the better, but I'm living proof that you don't need lab-grade cleaning protocols to pull it off. I'm in a desert, in a drafty old house with a bunch of dogs constantly in and out. There's all kinds of shit constantly wafting in the air here. You don't need to be anal to the point of having an actual clean room; just gotta give your hands and any tools/equipment a wipe down any time you're actively working with them. Keep a spray bottle of iso with you and don't be afraid to use it. It becomes habit pretty quickly.
EDIT: Don't wanna hijack this thread too much, so here's a link to an active shroom discussion thread if you wanna check it out:
I assumed refrigeration was pretty much mandatory for keeping spore solution viable maybe i f'ed that one up then???? oops. coulda swore it only said store in cool and dark. i'm bad with directions. lol
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