Some conks. My grandfather used to paint pictures on them 😀

Conk (Fungus)

A conk is a hard, shelf-like fungal growth commonly found on the trunks and branches of trees, produced by fungi like polypores or bracket fungi. These woody or leathery structures, such as the Artist's Conk (Ganoderma applanatum) and Turkey Tail (Trametes versicolor), often indicate tree decay as the fungi decompose wood. Conks play an essential role in ecosystems as decomposers but can weaken trees structurally. Additionally, certain conks, particularly the Artist's Conk, are used in art due to their smooth undersides, which can be etched or painted, creating detailed and durable designs.