Fire, fuels, and climate in coniferous forests of Idaho and Montana

Publication Type:

Magazine Article

Authors:

Kipfmueller, Kurt F.

Source:

Sage Notes, Idaho Native Plant Society, Volume 23, Issue 1, p.2-5 (2001)

Call Number:

U01KIP01IDUS

Abstract:

Over the course of the past summer fires burned widely across the western United States, scorching nearly 7 million acres nationwide and more than 2 million acres in Idaho and Montana alone. The 2000 fire season turned out to be one of the largest fire years on record in the United States. The season began with the Cerro Grande fire in New Mexico, an escaped prescribed fire which burned more than 200 homes in the city of Los Alamos, and culminated with large fires in Idaho and Montana. Politicians, the media, land managers, and the public were quick to blame these fires on deteriorating forest conditions due to past management practices. The effects of drought on fire regimes, however, sometimes take a backseat to anomalous fuel build-ups as culprits leading to widespread, severe fires. However, the effect of a two year La Nina-induced drought on these widespread fires cannot be ignored. Nor can the role of drought at long time scales. Fire is an important part of the ecology of western forests, but its characteristics and effects vary widely among different forest types. In general, fires occur less frequently but burn with greater intensity as elevation increases. Historically, fires burned relatively frequently but with relatively low intensity in lower elevation montane forests such as those dominated by ponderosa pine or Douglas fir. These forests typically experienced low-intensity fires at relatively short intervals (5-20 years) and are biologically adapted to this type of fire regime. Fires of this nature consumed most young trees and accumulated forest litter but did not substantially impact the larger, fire-resistant trees. In the subalpine forests of the Northern Rocky Mountains, however, fires occur at longer intervals (50-300 years) and often kill large patches of trees. Because fire has different characteristics in different forests, its relationship to environmental factors such as fuel and climate characteristics also varies.