Here we gather information about the current understanding of wildfire history in the Applegate Valley, and information about the Bureau of Land Management's fuels management program.
Fire in Southwest Oregon Interior Foothills
Fire is the key natural disturbance in southwestern Oregon, and has been influential in shaping the landscape. Many local plant species, and the animals that depend on them, rely on fire to maintain their habitats. Native Americans managed parts of the watershed with fire for at least 4,000 yr, but their practices were replaced by Euro-American mining, ranching, and very high-frequency burning in the early 1850s. Pre-Euro-American fire history is poorly understood for non-coniferous systems in the area, but better data are available for conifer systems. It appears that the policy of fire suppression has reduced fire occurrence and area burned across all vegetation types, as can be seen in the fire history below, compiled from BLM fire history records for the lower Applegate Valley.
Page by Olivia Duren. Updated 4/2010.
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Fire history for the Applegate Valley 1910 – 2007, derived from fire history data provided by the Medford District Bureau of Land Management. Early fires and fires < 40 ha are likely to be underrepresented. Fire suppression became effective in the late 1920 – early 1930s on some parts of the landscape, but was not effective until the 1940s or later in more remote parts of the landscape. Analysis and figure by O. Duren. Click for a larger figure.
Fuels management program of the Medford District BLM
Fire suppression is thought to have resulted in unnaturally large accumulations of fuel, which may exacerbate fire risks to natural and human resources. Josephine and Jackson counties in southwest Oregon are ranked 1st and 2nd in the western region for wildfire risk (largest developed area in the Wildland Urban Interface). Fire suppression is known to have caused changes in coniferous forests within the Applegate Valley, although its effects on oak woodlands and chaparral shrubland communities appear to be less pronounced.
In response to concerns about fire risks in the region, particularly in wildland/urban interface areas, land managers have been carrying out fuels reduction programs since the mid-1990s that are intended to reduce fire hazards. In some cases, it is hoped that treatments will also restore ecosystems that are assumed to have been altered by fire suppression. See an overview of the fuels management program (PDF), including a map of treated areas (current up to 10/2006).
Although thousands of acres have been treated each year, spanning both non-coniferous and coniferous communities, remarkably little is known about the impact of treatments on plant and animal communities, or about treatment impacts on intensity or severity of subsequent fires. Further, little is known about the basic ecology of pretreatment non-coniferous communities themselves, or how communities are impacted by treatments. What is the distribution of non-coniferous plant communities on the landscape, and what is their structure? How do these communities respond to the environment and disturbance, and how do they appear to have changed over time? Have non-coniferous communities been strongly affected by fire suppression? Do fuels treatments mimic natural disturbances? Are they able to recreate natural structures? Do treatments facilitate invasion by exotic species? Personnel from the Medford, OR office of the BLM, Oregon State University (OSU), and Southern Oregon University (SOU) gathered and analyzed data largely from oak woodlands, shrublands, and chaparral in the Applegate Valley to answer these questions.
The Joint Fire Sciences Program has fostered cooperative research between scientists and land managers that will inform adaptive management. The Medford District BLM's fuels reduction program has evolved over time, and will continue to evolve. Check out a summary of some lessons learned (PDF) from 10 years of monitoring vegetation response to fuels reductions in woodland and chaparral.
Oak and chaparral ecology and fuels management
in southwest Oregon
