Rhizomorphs are fine, root-like structures, consisting of aggregates of hyphae with an often distinct darker-coloured rind surrounding a central core of colourless hyphae. They vary from as thin as horse-hair to the thickness of a bootlace. Rhizomorphs are often associated with the base of the stipe, and sometimes fruit-bodies arise directly from rhizomorphs (at right angles). Where fruit-bodies are growing near the base of a tree, check under the bark of the tree for associated rhizomorphs.

Choose this state if: black rhizomorphs are absent.