Tamm Review - a Meta-Analysis of Thinning Prescribed Fire and Wildfire Effects on Subsequent Wildfire Severity in Conifer Dominated Forests of the Western US

This document evaluates how different forest management strategies influence the intensity of future wildfires across conifer-dominated landscapes in the Western United States. By synthesizing decades of empirical data, the researchers demonstrate that combining mechanical thinning with prescribed burning is the most effective defense, reducing subsequent fire severity by up to 72%. The study highlights a hierarchy in treatment efficacy and notes that addressing surface fuels is essential since thinning alone proved significantly less reliable at preventing high-severity burns. Furthermore, while these treatments remain robust under diverse weather conditions, their protective benefits diminish over time, typically halving in effectiveness after a decade.