It sounds like controlling the watermeal and duckweed is just like trying to control weeds in food plots. Get them whacked back this year, next year seeds that didn't germinate the previous year do, resulting in another crop of weeds. I read that some seeds (lambsquarter for instance) can stay viable for 1700 years and many other weed seeds are viable for over 70 years.

I wonder how many years WM and DW seeds stay viable?

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