I am selling a 4oz bag of natural organic rye grain berries fully colonized with the Golden Oyster mushroom fungus, that’s right we have taken the work, and cost out of buying a bag of sterilized rye grain, and the added expense of buying a spore syringe and you having to inoculate the bag yourself, and hope you don’t contaminate it in the process. What is grain spawn?: Grain Spawn is mushroom mycelium grown into certified organic rye grain which is ideal for inoculating sterilized substrates, or for use in unsterilized inoculations. We recommend using grain spawn within one to three months of purchase. Most species must be stored refrigerated. Spawn is simply a carrier to hold a specific strain of mushroom mycelium in ‘stasis’ until you, the cultivator, are ready to transfer it into another substrate such as a wood log, straw, compost etc. We incubate specialty mushroom strains in our laboratory, then cultivate them into a variety of forms for your use, including sawdust, grain, and dowel plugs. Each of these, once colonized by mycelium, is referred to as spawn. We also sell the other types of spawn here as well. This grain is ready to go, just mix it with straw, paper, coffee grounds, wood chips, yard waste etc.