I've been reading up on mushroom culture and would like to know if the common white 'pizza' mushroom can be grown on prepared grain substrate, or does it have to be composted horse manure? Is there a quick reference as to which mushrooms will be successful on a grain plug, or else on a prepared rice flour/vermiculite plug?

I've seen several videos that involve prepared grain 'cased' with sterilized soil.

Any examples of personal experience/advice will be appreciated!

--Rick in CT