Woodpecker Foraging and the Successional Decay of Ponderosa Pine

In 1998 we initiated a long-term study investigating the relationships between woodpecker foraging and snag decay processes in interior ponderosa pine forest communities located in Oregon and California. We describe temporal changes in snag structure and quantify both woodpecker foraging activity and relative sapwood decay in 144 ponderosa pine snags, ranging in age from 1 to 9 years (time since death). Preliminary results indicate that temporal changes in snag characteristics were reflective of both inherent insect activity and woodpecker foraging quality. Statistical analysis revealed no significant difference in cumulative woodpecker foraging abundance as snags aged, indicating that woodpecker foraging activity occurred primarily in the younger aged snags. Additionally, there was no correlation between woodpecker foraging intensity and relative sapwood decay. These results offer insights into the interactive biology of bark beetles, woodpeckers, and fungi in the decomposition of ponderosa pine.