Decay fungi break down wood components over time. The early stage of decay (incipient decay) is characterized by discoloration and the presence of â€œpunkyâ€? wood fibers. Punky wood is spongy wood that has experienced a loss of strength and structural integrity due to the decomposition of connective fibers. As the decay progresses, the cellular integrity of the wood deteriorates until small voids develop. Larger voids can develop where the decay started, and the boundaries of the incipient decay will continue to extend, reducing the integrity of the wood and, potentially, compromising the ability of the wood to provide the structural support required (Fig. 8). Advanced decay, the ultimate result of moisture absorbed into the wood through either ground contact or small cracks and drying checks on the wood above ground, is a severe threat to the long-term viability of wooden artifacts.
Fig. 8. Evidence of advanced decay . The below-ground portion of this marker is punky and easily breaks apart.
Insects Insect attack is generally a minor contributing factor to the deterioration of wooden artifacts, as most insects seek out wood that has already been compromised by high moisture content levels. However, a number of wood-boring insect species can cause significant damage to wooden artifacts. In the southeastern U.S. and other humid coastal regions in particular, insects are more likely to be an issue for wooden artifacts than in other parts of the country.
Annual Journal of the Association for Gravestone Studies