Historic Fires In The Central Western Cascades Oregon

Download or read book Historic Fires in the Central Western Cascades, Oregon written by Constance J. Burke and published by . This book was released on 1979 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: The history of fire between 1850 and 1977 in a portion of the Willamette National Forest in-the central Western Cascades of Oregon was documented using historical sources. Three types of records were available: (1) records and writings not primarily concerned with fire but yielding information about fire in context with human activities, (2) descriptive accounts of fires prior to 1910, and (3) statistical reports generated by the U.S. Forest Service from 1910 to the present. Corresponding to each type of record, this study was divided into three time periods: pre-1850, 1850-1909, and 1910-1977. Information about the pre-1850 period was drawn from reconstructions of aboriginal forest use by anthropologists, archaeologists, and enthnographers. Although four groups of aboriginal people inhabited areas within or adjacent to the study area, evidence is lacking for intentional Indian burning in the central Western Cascades. Unintentional burning from untended or abandoned campfires is probable. Coupled with naturally occurring lightning-caused fires, these fires were ample ignition to maintain an age class of 125 years or older in the forests of the central Western Cascades. Information about fires occurring between 1850 and 1909 came from a variety of historic sources. All chronicled fires were attributed to man. Many man-caused fires were related to specific human activities, including road building, sheep grazing, and camping. As human use increased, the numbers of fires increased. Conflicts in use occurred because of the threat of fire. Some activities, such as mining and railroading, were not causes of fire in the central Western Cascades. Lightning was not regarded as a cause of forest fires until after 1900. Fire records for the period from 1910 to 1977 were generated by the U.S. Forest Service. These records exist in various forms including fire maps, summary tables, and individual fire reports. Almost 60 percent of all recorded fires from 1910 to 1977 were lightning caused. While lightning ignited more fires, they were usually small and occurred in mid-summer. Man-caused fires although fewer, were larger and occurred throughout the fire season. An increase in the number of fires is paralleled by an increase in forest use. Two maps were constructed to illustrate the spatial distribution of man-caused and lightning-caused fires. Lightning-caused fires appear to be unevenly distributed over the landscape. Three areas exhibit a low incidence of lightning-caused fires. Lightning fires occur at higher elevations, where fuel accumulations are less, and tend to remain small. Man-caused fires exhibit a definite pattern corresponding with land-use. These fires tend to follow major transportation routes which are generally at lower elevations. Man-caused fires, ignited at lower elevations, have more chance to spread and become large fires.