Mycologist and author Peter McCoy of RadicalMycology.com takes on the question - In order to produce the most amount of Reishi mushrooms out of this sawdust spawn for home use, does it make sense to expand the sawdust spawn out by going back to sterilized grain first and then expanding out onto more sawdust bags or just take the sawdust spawn and expand it out onto more pasteurized sawdust bags? Basically, is there any advantage to taking mycelium back to grain once it is on sawdust?  To learn more about Peter and see all of the ASK Peter episodes visit permaculturevoices.com/peter.   Support the show at permaculturevoices.com/support.