From page 1: 'Evidence for the purposeful use of fire by American Indians--also termed Native Americans, Indigenous People, and First Nations/People in many ecosystems has been easy to document but difficult to substantiate. Many researchers and ecologists discount the fact that the American Indians changed greatly the ecosystems for their use and survival (Butzer 1992; Denevan 1992; Doolittle 1992; Krech 1999; Sale 1990; Whitney 1994). Fire scientists and ecologists often find old fire scars in trees going back hundreds of years. Geographers studying lake sediments often find evidence of charcoal layers going back thousands of years, attributing the data to prehistoric fires caused by global warming and drying conditions. Since the trees and sediments cannot document how the fires started, lightning becomes the easiest 'natural' explanation. However, there is growing literature that many or most of the natural fires were intentionally caused.'