Thanks to the fellow pondmeister david u, here is a link on how to keep those pesky trees from growing back. http://texnat.tamu.edu/BrushBusters/CutStumpsHardwood.htm Useful info anywhere you want to keep a tree from coming back, especially invasives. I used Remedy RTU around the pond because it uses vegetale oil instead of diesel. Go to keep those fishies happy!