Colorado Statewide Forest Resource Assessment

NATIONAL THEME: Protect Forests from HarmForest condition or health can be assessed by examining the interactionsbetween three components: a for est’s resilience to disturbance; its abilityto sustain a natural range of biological diversity; and its ability to meet thecurrent and future needs of people in terms of values, products and services(CSFS 2002). The majority of Colorado’s forested landscapes are considereddisturbance driven, meaning their condition is integrally linked with naturalcycles of wildfi re and insect and disease infestations, as well as periodicfl ooding, avalanches or windstorms. Without this regular rejuvenation, forestscan become overcrowded and less diverse than they were in the past. Thestress of competing for sunlight, water and other essential resources underthese conditions renders trees vulnerable to insect and disease activity, fi re ordrought, and sets the stage for much faster and more devastating events tomove across the landscape (CSFS 2002).In Colorado, the lack of regular disturbance is the culprit behind many of thestate’s forest health challenges. More than a century of virtual fi re exclusion,along with changes in land management priorities and practices, have leftmany of the state’s forests highly susceptible to wildfi re, insects and disease.Recent cycles of drought and the emerging impacts of climate change furtherexacerbate this situation.Restore Fire-Adapted Lands and Reduce Risk of Wildfire ImpactsOverview: Although fi re is only one of many processes that operate withina forest, it often is such a dominant process that to a great degree it candetermine the composition, structure and dynamics of the entire ecosystem(Pyne 1996). Over thousands of years, forests and associated vegetationhave adapted to a certain cycle and intensity of fi re. These adaptations, suchas thick bark or serotinous cones, enable vegetation to respond favorablyto these naturally recurring events. When fi re does not occur according tothese cycles, forest resilience can decrease and fi re events that do occur cancause long-term damage to soil, vegetation, wildlife and other ecosystemcomponents (Pyne 1996).In an effort to better classify the role fi re plays in various ecosystems,scientists have identifi ed fi ve primary fi re regimes that describe the frequencyand characteristics of historic (pre-settlement) fi res. In Fire Regime I, forexample, fi res return every 1 to 35 years, are of low to mixed severity, andgenerally replace less than 25 percent of the dominant overstory vegetation.In Fire Regime V, fi res occur every 200 years or more and usually are standreplacing. In recent years, scientists and land managers have developedan additional system to classify and assess the role of fi re using fi re regimecondition class (FRCC). This classifi cation ranks ecosystems from 1 to 3based on their level of departure from a set of reference conditions that refl ectthe vegetation and structure that would have existed on the landscape prior toEuropean settlement (FRCC Guidebook 2008).In Colorado, LANDFIRE data indicate that the forest types on 6.8 million acreshave signifi cantly departed from expected reference conditions. The primarycause of this departure is a management philosophy that virtually excludedfi re from the landscape for over a century. This exclusion has been particularlydamaging to forests in Colorado, including ponderosa pine, mixed conifer andpiñon-juniper, which evolved with frequent, low- to moderate-intensity fi res.26