Protecting the Wildland-Urban Interface in California: Greenbelts vs Thinning for Wildfire Threats to Homes

Abstract

This study utilized native chaparral and sage scrub shrubs planted in lightly irrigated greenbelts around homes to evaluate the impact on live fuel moisture content (LFMC) and predicted fire behavior. As to be expected LFMC varied markedly throughout the year being over 100% in winter in all species and treatments that included adjacent thinned native shrublands and untreated control shrublands. However, in the summer and fall there were marked differences between treatments. For most species lightly irrigated plants had the highest LFMC in the summer and fall, followed by thinned treatments and controls. These differences in moisture content coupled with structural differences in the vegetation contributed to expected differences in flame length and rate of spread. Lightly irrigated native shrubs planted around homes can reduce fire hazard while possessing other desirable features of utilizing native vegetation.