My shiitake blocks started getting moldy. I guess they were too old after all. No worries, though. I'm starting over with fresh ones and a head full of mistakes to learn from. In the meantime, I won't let them go completely to waste. I chopped the blocks up into 1" cubes which I'm soaking in a bucket of water. Later this afternoon I plan to dump them on an old firewood pile in the woods next to my house. Best case scenario: The mycelia find purchase and in a year or two there will be shiitakes sprouting out all over it. Worst case: They rot into soil. Seems like a decent outcome either way.
One other plan, to hedge my bets against being incapable of growing shiitake indoors: I just sterilized these dowel pegs, which I'm going to inoculate and use to impregnate some logs outside. There are also some dead trees on my property that I'll try pounding a few of these into, just to see what happens.