Historical Role of Fire on the Bitterroot National Forest


Stephen F. Arno

Document Type

Full Issue

Publication Date



Presents frequencies, intensities, and influences of fire on stand structure and composition on the Bitterroot National Forest in west-central Montana. Three study areas were established, each having a wide range of elevations and forest types. Findings are based upon study of nearly 900 individual fire scars on living trees, and on age-classes of shade-intolerant trees attributable to fire. During the period from 1600 to 1900 fires were frequent in most habitat types, and substantial amounts of forest survived most fires. Some high-intensity stand-destroying fires were also detected in certain habitat types on each study area. Results show that fire was historically a major force in stand development, but that is has been of minor significance during the past 50 years, possible because of organized fire suppression.


This item was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.