Mycelial sheets are formed of filaments (hyphae) that have grown as a result of a spore / multiple spores growing, which are 'fruit phase' of the fungus. The m

Mycelial sheets are formed of filaments (hyphae) that have grown as a result of a spore / multiple spores growing, which are 'fruit phase' of the fungus. The mycelial sheets are rendered 'inert' through one of an option of processes (for example baking it). A clearer visualisation of the materials here: the mycelial sheets used in research / production are as to spores as a plank of apple tree wood is to apple seeds. When you're working with the wood you do need to be cautious of the dust, but you don't need to be concerned about apple seeds sporadically appearing.