The effect of wood moisture on infection of Sitka spruce stumps by basidiospores of Heterobasidion annosum

In an inoculation experiment to test the effect of wood moisture content on infection of Sitka spruce ( Picea sitchensis ) stumps by basidiospores of Heterobasidion annosum , exposure to high rainfall increased infection in the heartwood and reduced sapwood infection compared to covered stumps. This was associated with a greater moisture content in both wood types. Within‐treatment variation in the amount of infection was high and it is suggested that endogenous factors in stumps may have a greater influence on infection than the environment or the availability of spores.