Report Nr. 3471 An Evaluation of Chemical Treatment and Burning on the Control of Autumn Olive (Elaeagnus umbellate)

Since ceasing extensive planting of autumn olive, the Michigan Department of Natural Resources has sought means to control the spread of autumn olive into open habitats. We conducted an evaluation of the effectiveness of 2 herbicides in combination with a prescribed burn to kill autumn olive at the Rose Lake Wildlife Research Area in East Lansing, Michigan. Sixteen clumps of autumn olive shrubs were treated with Garlon 3A, 16 clumps were treated with Glyphomax Plus, and 16 Control clumps were not treated with herbicide. After treatment, the field was burned in early September 2004. In September 2005, we evaluated the percent live canopy on the 48 autumn olive clumps. All 16 of the Garlon 3A treated clumps were dead (no live canopy). Three of the 16 Glyphomax Plus treated clumps were dead. All of the control clumps were alive. The percent live canopy was also used to evaluate impacts of the herbicide treatments on clumps. Treatment with Glyphomax Plus resulted in significantly more clumps in the lowest percent live categories than the Control. Results of this evaluation indicate that treatment with Garlon 3A in combination with a prescribed burn is an effective way to kill autumn olive while Glyphomax Plus followed by a prescribed burn significantly reduces the vitality of autumn olive plants, but does not lead to death.