FRCC History and Evolution
A growing body of research shows that a century or more of fire exclusion and other practices have negatively impacted many ecosystems. Some lands are now in poor ecological condition, whereas other landscapes are still functioning in a natural state.
Early research, by Sampson (1919) and Daubenmire (1947), devised relatively simple rating systems for characterizing ecosystem "health" and biodiversity. Since that time, classification systems have been refined for evaluating forests, riparian function, wildlife habitat, and other resource values. Ecosystems are assessed not only to derive condition, but also to diagnose trends and values at risk. Classifying fire regimes also has a long history, dating from the 1940s work of Harold Weaver, a Bureau of Indian Affairs forester. Since that time, other ecologists have developed systems to describe fire regimes.
In the simplest definition, a fire regime describes the basic "personality" of fire for a given vegetation type. Although fire frequency and severity are the most commonly used descriptors, many other aspects have been studied, such as fire spread patterns, fire seasonality, and post-fire patch dynamics.
As early as the 1980s, scientists and fire managers warned of an escalating fire problem in the United States. Many fire-prone landscapes seemed to be experiencing increasingly severe or more frequent wildfires. These apparent trends likely stemmed, in part, from past management practices such as long-term exclusion of fire. Consequently, many ecosystems have become degraded. These problems underscore the need for an assessment tool to help interpret landscape condition and possible fire regime departure from the natural state. As a result, the Fire Regime Condition Class (FRCC) method was born. FRCC is a tool that categorizes a landscape's potential degree of departure from its reference condition.
The FRCC system uses two sets of descriptors that, when combined, can be used to diagnose fire regime condition class. The first set of factors measures vegetation composition and structure changes. The second set measures possible changes in fire frequency and severity. FRCC also uses a fire regime classification system of five broadly defined fire regimes. This FRCC system is explained further in the online training and in the Interagency FRCC Guidebook
FRCC: How it Works
Simply put, FRCC assessments determine how similar a landscape's fire regime is to its natural or historical state. Fire regime condition classes are broken down into three categories: 1, 2, and 3. Landscapes determined to fall within the category of FRCC 1 contain vegetation, fuels, and disturbances characteristic of the natural regime; FRCC 2 landscapes are those that are moderately departed from the natural regime; and FRCC 3 landscapes reflect vegetation, fuels, and disturbances that are uncharacteristic of the natural regime. So essentially, a landscape in FRCC 1 has key ecosystem components intact, such as large old trees and soil characteristics that would naturally be found on that site. A landscape with an FRCC rating of 3 indicates that the land is not very similar to its natural regime in terms of its vegetation or disturbance or both. An FRCC 3 landscape has lost key ecosystem components; an example could be the loss of characteristic large trees due to uncharacteristic wildfires that occurred in uncharacteristic fuels.
Daubenmire, R., 1947 Plants and Environment: A Textbook of Plant Autecology. John Wiley & Sons, New York.
Samson, A.W. 1919. Plant succession in relation to range management. U.S. Deptartment of Agriculture Bull. 791.
