Originally Posted by prefetch
okay - i think this is eurasian watermilfoil.

it's got 4 branches off the stem, and each branch has about 12 little branches off of that. from what i understand, i'm in trouble because this is an invasive species and it'll eventually take over my entire pond.

It is EWM. Use Fluridone (Sonar A.S. or equivalent) at the rate of 10 PPB now to kill most of it, and again in late May to kill any germinated and growing seeds. It may take 3 treatments over 3 years to 99% eradicate it. At 10 ppb dose you won't affect any other plants in the pond. Only problem would be if you had constant water flowing in and out of your pond. The 10 ppb dosage has to be there for 30-45 days to kill it.

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