Distribution Native to Eurasia, Australia, and Africa Colonized Northeast United States in Mid 1800’s Was present in Midwest ponds and lakes by 1930’s Currently found in all continental states except Maine and S. Carolina
Description/Identification Alternate two ranked leaves Crisp textured leaves Leaf margins are wavy and toothed Distinct mid-vein Highly reduced flowers on aerial spikes Produce turions
Life Cycle Biology Cold/Cool water plant Active growth in winter Maximum density in late spring Falls dormant in early/mid summer
Life Cycle Biology Reproduces by turions, seeds, fragmentation, and rhizomes Forms turions in late spring Germination of turions is very high Turions remain viable for several years
Dispersal Mechanisms Boats, trailers, and other human assistance Waterfowl Currents
Impacts Reduced recreational activities Decrease in property value Disrupt navigation Trigger algae blooms in summer Trigger dissolved oxygen depressions
Viable ManagementTechniques/Control Options Education/Prevention Physical Removal? Biological? Chemical Control
Chemical Control Early Treatments Endothol Aquathol Aquathol Super K Fluridone Sonar AS Sonar Q Diquat Reward Weedtrine
Chemical Control Endothol Aquthol K: For whole lake treatments use 0.75 – 3.0 ppm (0.45 - 1.9 gallons per acre foot). For partial lake trements use 1.5 – 5 ppm (1.0 – 3.2 gallons per acre foot). Aquathol Super K: For whole lake treatment use 0.75 – 1.5 ppm (3.3 – 6.6 lbs. per acre foot). For partial lake treatments use 1.5 – 5 ppm (6.6 – 22.0 per acre foot). Best results in early to mid spring when water temperatures are between 55 and 70 degrees F.
Chemical Control Fluridone Sonar A.S. Aquatic Herbicide: Whole lake treatments only at 20 – 30 ppb total product application Sonar Q Aquatic Herbicide: Whole lake treatments only at 20 – 30 ppb total product application Perform FasTEST to confirm treatment concentration Early treatments most effective. Has shown excellent results in winter applications as a preventative in isolated cases. Do not use once the plants are mature and forming turions.
Chemical Control Diquat Reward: Use 1 - 2 gallons of Reward per acre of vegetation. Weedtrine D: Use 5 – 10 gallons Weedtrine D per acre of vegetation Best results in early to mid spring when water temperatures are between 55 and 70 degrees F.
Questions?Managing Aquatic Resources Since 1966