| Summary: | Conifer plantations in northeastern Minnesota are important browse areas for moose (Alces alces). The U.S. Forest Service has recently shifted to glyphosate (Roundup) as the predominate herbicide for controlling hardwood shrub and tree competition in plantations. Glyphosate is a systemic herbicide that usually kills the entire plant, so little resprouting occurs. The previously preferred herbicide, 2,4-D, generally left roots alive that resprouted. We sampled available browse in glyphosate and 2,4-D treated plantations. Three years after spraying, the glyphosate treated plantations averaged only half the available browse as the 2,4-D treated plantations. Grass and raspberries (Rubus spp.) are not controled the year after spraying with glyphosate because this herbicide has no residual effects. We could not measure long-term comparative effects because glyphosate was not used in this region before 1981. This report covers only the first of a 2-year study.
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