WRT the first question - when the ponds fills, that existing grass, clover, etc. will provide a beneficial habitat for the new pond life to live in and on. This will be a good thing, so I wouldn't worry about trying to keep it mowed or clearing it out. It will also help control erosion from precipitation while the pond is filling, an additional benefit.


"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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