CHAPTER 5.
SUMMARY AND CONCLUSIONS
The hypothesis of this dissertation is that western Oregon Indian burning practices of 1491-1848 had a direct effect on subsequent patterns of catastrophic forest fires that took place from 1849 to 1951 in the Oregon Coast Range [Chapter 1]. These patterns are shown to vary between northern, eastern, western, and southern parts of the Coast Range due to differences in cultural and tribal traditions (see Map 3.01), topography (see Map 1.02), climate (see Table 1.01), vegetation (see Map 1.09), and distance from the ocean (see Map 4.01).
The "cultural legacy" of long-term Coast Range Indian burning actions is shown to have a direct effect on subsequent patterns of catastrophic forest fires in the same region (see Chapter 4.C.). This study clearly demonstrates a high rate of coincidence between the land management practices of precontact Indian communities of the Oregon Coast Range, and the causes (see Table 4.02), timing (Table 3.04 and Table 4.01), boundaries (Map 4.13), severity (see Chapter 4.A.) and extent (see Map 4.01) of subsequent catastrophic forest fires in the same area.
These findings differ significantly from current assumptions that Indian burning actions affected a relatively minor portion of the landscape (Vale 2002), that Coast Range lightning fires had greater influence over precontact vegetation patterns than human fires (Whitlock and Knox 2002), and that precontact vegetation could be characterized as a "blanket of old-growth" Douglas-fir forests (FEMAT 1993). Instead, early journalists, painters, surveyors, photographers, timber cruisers, and immigrant residents [Chapter 2] found a lush, thriving mosaic of forests, woodlands, prairies, berry patches, camas fields, and thousands of contiguous acres of oak savannah grasslands, wildflowers, "Indian oats", and "Indian peas"; all connected by a well-established and maintained network of foot trails and canoe routes [Chapter 3].
In the 1840s a dramatic transition took place, in which the few thousand Indians who remained alive in the Coast Range following a series of devastating plagues and epidemics, were displaced by thousands of European American immigrants and hundreds of herds and flocks of domestic grazing animals. For the first time in millennia, the landscape was not being managed primarily with fire. As hundreds of new species of plants and animals were being cultivated and released into the environment by newly arrived immigrants, a century-long series of some of the largest and most spectacular forest fires in history was initiated with the 300,000+ acre Yaquina Fire [Chapter 4].
An abundance of historical evidence exists that can help reconstruct precontact vegetation patterns and human burning practices in western Oregon. This evidence can also be used to better document local and regional forest fire histories (Chapter 2 and Appendix D).
Precontact Oregon Coast Range Indians used fire to produce landscape patterns of trails, berry patches, root and bulb fields, nut orchards, woodlands, forests and grasslands that varied from time to time and place to place. These variations were due in part to demographic, cultural, topographic, vegetative, and climatic differences that existed throughout the region.
Local Indian families systematically managed native plants in the Oregon Coast Range in precontact time. Plants were maintained in even-aged stands, usually dominated by a single species, throughout all river basins of the Range. Oak, filberts, camas, wapato, tarweed, yampah, strawberries, blackberries, huckleberries, brackenfern, lilies, onions, nettles, and/or other plants were raised in select areas by all known tribes, over large areas and long periods of time.
Current scientific, resource management, and policy assumptions regarding the abundance and extent of precontact western Oregon old-growth forests in the Oregon Coast Range may be in error. Although old-growth (more than 200-year-old) conifer and hardwood trees are common throughout the Range--and probably have been common throughout the 460-year time span of this study--they existed in the forms of stands, pockets, strips, belts, groves, and individual specimens and varied dramatically in total extent and population numbers from time to time. This is a significantly different finding than the "blanket of old-growth" description that has been used to characterize 60%-80% of the landscape of the Range by a number of scientists and politicians during the past two decades.
E. Comparison of Indian Burning and Catastrophic Fire Patterns
Similarities and differences between Indian burning and catastrophic fire patterns in the Oregon Coast Range are summarized in Table 5.01. This table shows a high rate of coincidence between the land management practices of precontact Indian communities and the causes, timing, boundaries, and general extent of subsequent forest fires in the same area.
|
Fire Characteristics |
Indian Burning |
Catastrophic Fires |
|
Causes |
People |
People |
|
Location of Ignitions |
Travel corridors and destinations |
Travel corridors and destinations |
|
Wind directions |
Variable |
East |
|
Seasons |
Late summer/early fall Late winter/early spring |
Late summer/early fall |
|
Frequency |
Daily |
Years or centuries |
|
Extent |
100,000s of acres annually |
100,000s of acres per occurrence |
|
Boundaries |
Ridgelines, riparian areas, forested areas, ocean |
Ridgelines, riparian areas, unforested areas, fogbelt forests |
|
Wildlife Habitat |
Stable, sunny, high protein mosaic of grasslands and forests |
Sudden changes in wildlife demographics and habitat patterns |
Table 5.01 Comparison of Indian burning and catastrophic fire patterns.
Indian burning patterns, by definition, are caused by people. Occasional fire escapements were probably a significant part of the landscape pattern created by daily firewood storage and use, situational patch burning, and seasonal broadcast burning. Firewood burning was a daily occupation by many (or most) precontact Indians. Patch burning practices were more likely to take place during seasonal periods, but also could be performed at about anytime weather and fuel conditions permitted. Historical accounts of broadcast burning activities in the Coast Range occur during two fire seasons: late winter/early spring "fern burning" and late summer/early fall "field burning". The development and maintenance of transportation corridors, extensive oak savannahs, prairies, berry patches, filbert groves, camas fields, lawns, and balds by Indian burning practices (Table 3.03) also resulted in beneficial habitat to a number of plant (Table 3.05) and animal (Table 3.06) species. During wildfire events, these areas could also function as "refuges" for threatened wildlife species.
Regional tree ring studies were used to determine a 300-year precipitation pattern (Graumlich 1987)that identified specific years and specific decades (1790s, 1840s, 1860s, 1920s, and 1930s) of prolonged regional drought. The annual events seem to have no significant relationship to Coast Range fire history, but the prolonged droughts correlate closely with major forest fire events identified in Chapter 4. All of these fires, however, are known or believed to have occurred during the late summer-early fall months of August and September. Thus, there is a strong correlation between fire events and seasonal weather patterns, but people, rather than lightning or other weather-related causes, are responsible for the large majority of fires in the Coast Range (see Table 4.02).
Topography plays an important part in affecting burn patterns of Coast Range forest fires. In heavily dissected areas, large areas of forest typically avoid being burned. In "rolling" areas of topography, almost all trees over large expanses of land might be killed. "Flat" areas of the Range have typically been used by people for thousands of years and thus not been subjected to significant forest fires at all.
Land ownership patterns also play a significant role in landscape patterns of purposeful burning and large scale wildfires. Precontact burning practices varied significantly between Chinookan, Kalapuyan, Athapaskan, and Yakonan tribes, for example (see Map 3.01 and Chapter 3.D.). Current forest landownership patterns of the Oregon Coast Range correlate closely to historical catastrophic fire patterns (see Map 4.01; Map 6.01; and Chapter 4.D.).
Information provided by this study should be of value to researchers, educators, wildlife managers, forest landowners, and others with an interest in the history and resources of the Oregon Coast Range.