Adult cottonwood over 500 gallons daily according to some experts I know here in NE. Couple that with evaporation and/or seepage and it's significant losses daily. I have heard that willows are nearly as aggressive. I walk the margins of my ponds monthly and pull or spray any cottonwood, willow or cattail saplings I encounter.

Conifers are my preferred choice for windbreaks as they won't drop leaves/twigs adding to organic load in a pond. Also they are much more dense and block wind more effectively. Not sure what species perform well where you live - here the Eastern Red Cedar is ubiquitous, cheap, hardy, drought tolerant, and nearly impossible to kill.

Many men go fishing all of their lives without knowing that it is not fish they are after. ~ Henry David Thoreau

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