Mark, Each early summer, curlyleaf dies back quickly in my pond similar as if I had used a herbicide. I would expect coontail and any other underwater plants to start growing well due to lack of competition and more light penetration to bottom area when the curlyleaf canopy dies.

Curlyleaf is supposed to be suseptable to 10-15 ppb of floridone (Sonar). This equates to 1.25 to 1.891 ounces or 37-55.5 ml per 1 million gallons of pond water. I am not sure yet what the best time frame window and water temperature are for treatment.

aka Pond Doctor & Dr. Perca Read Pond Boss Magazine -
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