Changes in development near public forest lands in Oregon and Washington, 1974-2005: Implications for management

Development owing to population increases over the last 30 years has greatly affected forested lands in the United States. To assess and compare increases in development, we counted changes in the number of structures on a systematic grid of photointerpreted points around public forest land in Washington and Oregon. Areas bordering public forest land are showing substantial increases in development, with the number of structures on private lands near almost all types of public forest more than doubling between the 1970s and 2000s. Lands bordering Washington’s Department of Natural Resources lands have more than twice as many new structures along their edges compared to other public owners. In Oregon, the greatest amount of development occurred along the edges of Bureau of Land Management forests. The greatest increases in structure density along the borders of public forests occurred in Pierce, King, Snohomish, and Clark Counties in Washington, and Deschutes County in Oregon. The continuing development pressure along the edges of public forests in Washington and Oregon has numerous consequences, including increased road density with more human-caused ignition of wildfire, higher probability for invasive species, greater demand for local recreation, higher fire suppression costs, and increased complexity for managers trying to reduce wildfire hazard through fuel treatments.