Fire History

A major goal of managers in fire-prone forests is restoring historical structure and composition to promote resilience to future drought and disturbance. To accomplish this goal, managers require information about reference conditions in different forest types, as well as tools to determine which individual trees to retain or remove to approximate those reference conditions.

Ecological departure, or how much landscapes have changed from a natural range of variation (NRV), has become a key metric in forest planning and restoration efforts. In this study we define forest restoration need as the specific change in structural stage abundance necessary to move landscapes into the NRV.

We extend a published 9000 yr fire history record from Little Lake, in the Oregon Coast Range, to 35,000 yr and compare it with the established pollen record from the site. The fire history is based on a high-resolution analysis of charcoal preserved in lake sediments, providing a fire history record that spans the Last Glacial Maximum in North America.

The rain shadow forests of the Olympic Peninsula exemplify a mixed-severity fire regime class in the midst of a highly productive landscape where spatial heterogeneity of fire severity may have significant implications for below and aboveground post-fire recovery.

Fire regimes structure plant communities worldwide with regional and local factors, including anthropogenic fire management, influencing fire frequency and severity.

High-severity, infrequent fires in forests shape landscape mosaics of stand age and structure for decades to centuries, and forest structure can vary substantially even among same-aged stands. This variability among stand structures can affect landscape-scale carbon and nitrogen cycling, wildlife habitat availability, and vulnerability to subsequent disturbances.

Context In the interior Northwest, debate over restoring mixed-conifer forests after a century of fire exclusion is hampered by poor understanding of the pattern and causes of spatial variation in historical fire regimes.

A warming climate, fire exclusion, and land cover changes are altering the conditions that produced historical fire regimes and facilitating increased recent wildfire activity in the northwestern United States.

An understanding of how historical fire and structure in dry forests (ponderosa pine, dry mixed conifer) varied across the western United States remains incomplete. Yet, fire strongly affects ecosystem services, and forest restoration programs are underway.

Fire frequency is changing globally and is projected to affect the global carbon cycle and climate.