In 2010, the District gathered experts from around the US to form a collaborative effort to research the growth cycle, habitat, and herbicide options to better understand Flowering Rush and develop better management strategies. The partnership included the Pelican River Watershed District, Mississippi State University Geosystems Research Institute (GRI), Concordia College (Moorhead, MN), US Army Corps of Engineer Research and Developments Center (USACERDC), and the Minnesota Department of Natural Resources-Ecological and Water Resources Division.
In order to most effectively reduce Flowering rush populations, submersed (below water surface) Flowering rush was targeted for the treatment research project. The growth cyle and habitate studies were used to refine herbicide application timing and water depths for treatments. Small-scale herbicide trials and an in-lake dissipation study were conducted in 2010-11. Based upon these promising results, in 2012, the first operational-scale of Flowering rush in-lake treatments were conducted on Detroit, Curfman, Sallie and Melissa lakes. In 2013, the treatment areas were expanded due to the significant reduction of below surface plants and roots following treatment with limited impact on native plant species. In 2015, the District began adapt the management plan to reduce the frequency of treatment for low density areas. Currently the District treats populations annually with the adaptive management plan.
ECOLOGY AND PHENOLOBY OF FLOWERING RUSH
Ecology & Management of FR in Detroit Lakes, MN- Marko, Madsen, Wersal, Marko, Skogerboe-2012
Ecology of FR in Detroit Lakes Becker County MN-Marko, Madsen, Olson, Smith, 2012
FR Ecology and Phenology Summary Marko
Evaluations of Contact Aquatic Herbicides for Controlling two populations of Submersed FR
Summary of Evaluations of Contact Aquatic Herbicides 2011
Evaluations of Systemic Aquatic Herbicides for Controlling two populations of Submersed FR
Herbicide Trails for Mgmt of FR in DL 2011
Herbicide_Trials for Mgmt of FR in DL_2012_-_Final
Efficacy of combinations of diquate or triclopyr w flouridone for control of FR
LAKE-WIDE HERBICIDE TREATMENTS
LW Herbicide Treatments Detroit_Lakes_2013_Report_-_FINAL
LW Herbicide Treatments Detroit_Lakes_2014_Report_-_FINAL
DEVELOPING AN ADAPTIVE MGMT PLAN FOR FLOWERING RUSH
TREATING MIXED STANDS OF FR AND BULRUSH ON LAKE SALLIE
In 2015, the District began a 2-year pilot study to treat mixed stands of Flowering rush and native hardstem Bulrush on the east side of Lake Sallie. Flowering rush was invading and displacing a 60-acre area of critical hardstem bulrush habitat. The study involved a small 5-acre test plot and concluded treatments had no damaging effects on the native Bulrush and significantly reduced Flowering rush populations. Other native plant species such as the Pond Lily reestablished in the treated areas. The treatment areas were expanded to 23 acres and in 2017 and the entire mixed stand areas (approximately 60 acres) were treated in 2018.