July 7, 2003 Ralph Phillips, Farm Advisor
Range/Natural Resources and Livestock
The Impact of Native Californians on Their Environment
A four-year study by Kat Anderson, for Yosemite Research Center, entitled "Indian Fire-Based Management in the Sequoia Mixed Conifer Forests of the Central and Southern Sierra Nevada" has presented interesting concepts regarding the influence of Native Californians on their environment. Her work combined the sciences of Anthropology and Ecology.
Anderson writes that many people feel that North America was pristine when Europeans arrived; however, her work demonstrates that the Native Americans were, in fact, managing the environment on a sustained base to meet their needs. The natives used burning, pruning, weeding, tillage, sowing and selective harvesting as "horticultural" practices to maintain their traditional gathering sites.
Western Mono women fired acres to improve the gathering grounds for edible seeds such as snowdrops and sunflowers. Sierra Miwok men burned areas, then planted seeds of tobacco in these spots and carefully tended patches to increase leaf size and improve taste. Many tribes buried patches of wild carrots and sanicles to eliminate competitive shrubs and grass, keeping areas open and increasing the size and quality of edible tubers. After farewell to spring, seeds were gathered, natives then burned the area and scattered some seeds to insure a future crop.
Black oak areas were set on fire to control insects that fed on the acorns. Fire reduced shrub growth which competed with the tree for nutrients and cleared the ground, making acorn gathering easier. Burning black oak areas also stimulated long suckers at the base of the tree which were used to make looped stirring sticks by the Yokuts and Miwok and basketmaking for the Western Mono.
Much of the material needed for making baskets, ceremonial items, clothing, games, snares and traps, structures, tools and weapons required shoots of trees or shrubs that were long, straight and flexible. The best source of these shoots was from plants that had burned. After a "cool" fire, many trees and shrubs send up long slender shoots. The natives preferred shoots that were one to two years old because older shoots tended to branch and became hard and brittle. Burning or managing trees and shrubs also produced more of the deserved shoots than unmanaged. For example: unmanaged redbuds would produce an average of one, 6-foot and three, 3-foot shoots, where managed or burned redbuds would produce an average of twenty-five, 6-foot and twenty-five 3-foot shoots. The same type of response to management occurred with sourberry and buckbrush. By managing collection areas, natives had to spend less time looking for plants to meet their needs. A burden basket would required over 1,200 sticks of sourberry. This would require collecting 400 patches of unmanaged sourberry but only 12 managed patches.
Fire management by native people drastically reduced the chances of major wildfires. They would burn small areas in October and November. These fires would burn slow and "cool", and they would only remove underbrush and reduce vegetation. They would burn areas on a two- to six-year cycle. This practice of constraint burning would reduce the fuel load, thus reducing the threat of major wildfires.
Burning increased the plant diversity of the ecosystems. Pristine or climax ecosystems contain only a few plants that are suited to the climax, where subclimax systems are made up of a larger number of plant species.
Anderson has brought up several other notable points regarding the impact of Native Californians on California Native vegetation. People curious in these ideas would find her full report interesting reading. A complete report is available for a fee through the Yosemite Association at 209-379-2648, ext 18.