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<br /> <br /> <br />Community Wildfire Protection Plan 15 September 2018 <br />3.5 Vegetation <br />3.5.1 Fire Adapted Landscape <br />Historically Kittitas County has undergone frequent low-intensity fire, like much of the lower and <br />mid-elevation forests, but resulting primarily from over 100 years of successful fire suppression <br />activities, these areas have seen excessive fuel buildup, altering the historical fire regime intensity <br />and severity. The most recent forest health assessment for the Okanogan and Wenatchee National <br />Forests found widespread susceptibility to insect and disease outbreaks and large-scale severe <br />wildfire (USFS 2004) The report found that climate and fire suppression were the primary drivers of <br />this change. The health of shrub steppe habitat in the eastern county has also declined increasing <br />the risk of range fire. <br />3.5.1.1 Forest Vegetation <br />Woodland fuels are mostly present in the western half of the county. As you move west the forest <br />transitions from wet deciduous and shade tolerant conifer through dry conifer (ponderosa pine, <br />Douglas-fir) mid-elevation conifer (grand fir, western larch, western hemlock), to high elevation wet <br />conifer (mountain hemlock, pacific silver fir). Wooded areas tend to be on steep terrain intermingled <br />with grass and shrubs providing an abundance of ladder fuels which leads to horizontal and vertical <br />fuel continuity. These factors, combined with arid and windy conditions characteristic of the river <br />valleys in the region, can result in high intensity fires with large flame length and fire brands that may <br />spot long distances. Rates of fire spread tend to be lower than those in the grasslands; however, <br />intensities can escalate dramatically, especially under the effect of slope and wind. Such fires present <br />significant control problems for suppression resources and often results in large wildland fires. <br />Furthermore, exceptionally hot and dry summers, overcrowding, and unprecedented forest insect <br />infestations are causing forested areas to become more and more susceptible to severe wildfire. <br />3.5.1.2 Rangeland Vegetation <br />Sagebrush is found throughout the mid to eastern edge of Kittitas County and is of great concern as <br />ladder fuel intermixed with stands of mixed conifers. Sagebrush is highly susceptible to fire and <br />rarely re-sprouts. Under historic conditions, sagebrush took approximately 20 years to reach pre- <br />burn densities following a wildfire event. Without periodic fire, sagebrush reaches an uncharacteristic <br />old-growth form with increased height, woody stems, and thick accumulations of leaves – all highly <br />flammable with fire behavior that is very similar to crown fires in larger conifers. Changes in fire <br />occurrence along with fire suppression and livestock grazing have contributed to the current condition <br />of sagebrush in the planning area. Introduction of annuals, especially cheat grass, has increased fuel <br />loads so that fire carries easily, increasing the potential for significant and dangerous fire behavior.