Which moisture content is too high for fungi to effectively grow in wood?

Fungi require a certain level of moisture content in wood to thrive, and their growth becomes problematic when the material is too saturated. Typically, wood with a moisture content above 20% creates an environment conducive for fungal growth, as this is the threshold at which decay fungi begin to flourish.

When the moisture content of wood reaches levels around 75% to 80%, which is extraordinarily high, this does not present an optimal condition for fungi to grow effectively within the wood itself. At these elevated moisture levels, the wood may become waterlogged and potentially experience a type of decay that is primarily caused not by fungi, but by anaerobic processes. In such cases, excessive moisture can lead to conditions that inhibit the mechanisms fungi require for growth, leading to a different array of decomposition processes rather than traditional fungal decay.

Therefore, while a moisture content of 20% is ideal for fungal activity and something beneath that level might restrict growth, a moisture level in the range of 75% to 80% is too high for fungi to effectively grow in wood. This understanding helps pest control professionals determine moisture levels that might risk wood structures to different forms of decay and informs their actions in treating and preventing wood-destroying pests and organisms.