View article

This study was designed to test the hypothesis that herbicide (glyphosate, active ingredient) application for conifer release would reduce species diversity (measured as richness, Simpson's index, and Shannon-Wiener index) of both plant and small mammal communities over a 5-year period in young sub-boreal spruce (Picea engelmannii Parry ex Engelm. x Picea glauca (Moench) Voss) forest. Four treated and four untreated (control) sites were studied near Prince George in central British Columbia, Canada. Crown volume index of shrub vegetation was reduced by herbicide application. Species richness of shrubs was reduced in the first year after treatment and remained lower on treated sites throughout the 5-year period. Both indices of shrub diversity, however, were not different over the 5 years. Herbicide treatment initially reduced crown volume index of herbaceous vegetation, but values quickly recovered to …