What external signs can reveal wood-decay fungi in trees?

External signs of wood-decay fungi in trees primarily manifest through the presence of fungal reproductive structures on the exterior of the plant. Key indicators include:

• Fruiting Bodies: The most prominent signs are hoof- or shelf-shaped fungal structures known as conks, brackets, or punks, which develop along the trunk and branches.12
• Mushrooms: Clusters of mushrooms (or toadstools) may appear at the base of the trunk or at the sites of previous wounds.312

The presence of these fruiting bodies or mushroom clusters typically indicates that extensive decay has already occurred within the wood. While the internal wood may become discoloured, lightweight, soft, spongy, stringy, crumbly, or powdery, these external structures serve as the primary visual evidence for diagnosis. It is important to note that these fungi generally enter trees through unprotected wounds, making proper pruning and protection against mechanical injury essential for prevention.132