Logging Impacts on Bitterbrush in the Lodgepole Pine-Pumice Region of Central Oregon

Abstract

The effect of logging on factors influencing production of bitterbrush in the lodgepole pine forest of central Oregon was evaluated. Production of bitterbrush in logged areas was approximately the same or greater than in adjacent nonlogged areas even though an average of 43% of the bitterbrush plants were lost during the logging operation. Bitterbrush plants growing in logged areas had leaders 2.5 cm longer than plants in nonlogged areas with 71% of their production in terminal and lateral leaders. Plants in nonlogged areas had only 45% of their production in the developed leaders. Plants taller than 40 cm were more frequently destroyed during logging operations than smaller plants. Plants 20-40 cm in height accounted for the greater production response after logging. Densities of germinated rodent caches of bitterbrush were much lower in logged areas. Percent canopy cover and density of lodgepole pine were highly correlated with cache densities of bitterbrush in logged areas.