For a second year, Northwest Aquatic Eco-Systems along with UW Botanic Garden will begin spray work to control Lysimachia vulgaris (garden loosestrife), a state-listed noxious weed occurring along Union Bay shorelines including the Union Bay Natural Area and the Arboretum’s Foster and Marsh Islands the first week of August. King County requires control of this aggressive and invasive weed, which poses a serious threat to the native character of area wetlands. In 2009, DoE provided a 5-year grant for $75,000 to fund loosestrife control.
In mid-July members of King County’s Noxious Weed Control Program and UW Botanic Gardens staff mapped the extent of the weed in the areas listed above. Comparison of the maps from year 1 to year 2 demonstrated slight control had taken place. Once again the weed will be controlled with an aquatically approved herbicide by the contractor, Northwest Aquatic Eco-Systems using airboats and other specialized equipment.