Performing Department
College of Forestry and Conservation
Non Technical Summary
Old-growth, fire-dependent stands of ponderosa pine and western larch are declining at an alarming rate. Yet as silvicultural restoration plans are being implemented, our understanding of the heterogeneity of fuel conditions and wildfire potential have been relatively unexplored. Mixed severity fire regimes associated with ponderosa pine/ western larch forest types are generally less predictable and less understood than other fire regimes. Information generated from the study will not only provide insight into this project's probable effects on fire hazard, but will also describe the natural heterogeneity of fuels and the potential fire behaviors evident in old growth stands. This information will be increasingly valuable in the development of future old-growth restoration treatments in these mixed-severity fire regimes.
Animal Health Component
75%
Research Effort Categories
Basic
25%
Applied
75%
Developmental
(N/A)
Goals / Objectives
The purpose of this project is to sample stand, understory vegetation, and fuels conditions in old growth ponderosa pine / western larch stands to estimate their structural compositional deviation from historical conditions, to model potential wildfire behavior with and without thinning and/or fire restoration treatments, and to determine the effects of treatments on designated old growth status. The project is designed to meet the Forest Service's need to document vegetation and fuels conditions in fire-adapted forests following a long absence of fire, to estimate current potential wildfire behavior, and to study management options for restoration. This project will provide documented evidence of old growth ponderosa pine/ western larch stand conditions to be compared with designated Forest Service old growth standards before and after virtual or actual management treatments of thinning and/or prescribed fire. Results of these documented examples of vegetation and fuel conditions in several old growth stands following decades of fire exclusion will also include a projection of the sustainability and successional pathway of these stands, and to test the effects of mitigating restorative options.
Project Methods
The research is anticipated to be over a five year period with two phases. Future phases will be determined pending anticipated continued funding. Methods for Phase One will included field sampling according to the mutually acceptable study plan. A summary of data by stand, comparison of vegetation (trees and understory) and fuel conditions among stands, and modeling of fire behavior in each stand with and without virtual thinning and fire treatments will be performed. The study will utilize collected stand data in with the FVS-FFE fire behavior model and FIREMON database to: 1) define surface and aerial fuel loadings; 2) describe the distribution of predicted fire behavior attributes at the plot scale and compare differences in the heterogeneity of fire behavior possible between different old-growth stand and fuel conditions; 3) describe the type of fire behaviors possible under various environmental conditions for each old-growth stand condition; 4) model fire behavior by simulating the proposed treatment and compare predicted fire behavior for each stand condition; and 5) compare the fuel loading and modeled fire heterogeneity of a mesic site on the Flathead National Forest and an arid site on the Bitterroot National Forest.