I have a lot of trees on the dam of my 3/4 acre pond. The pond is about 40 yrs old, and I have been trying to resurrect it since buying the property two years ago. The trees range in size from saplings, which I have removed, to 12" diameter. The trees on the top of the dam don't worry me as much as the ones on the down stream face. Last summer there was a slow trickle from the base of one tree located at the toe of the downstream side; the pond just reached full again last week after drawdown, so I don't know if that particular leak is still active. Also, the water level would typically go to full pond after a heavy rain, then rapidly drop to a constant level about 3' below full. My suspicion is that this tree, and possibly others, are lowering the water to that constant level. I can't afford to break the dam and rebuild, so are there any options? I know that it is generally recommended to only remove trees 4" diameter and smaller, but since I have seen leakage around this tree would it be worth cutting the tree? As the roots rot I could do a winter drawdown and cover the suspect area with clay. Would adding bentonite over the suspect area without removing the tree help?

I have removed Mesquite and Willow trees on and on the back of the dam using Remedy. Be careful not to get any in the water. I do a basil treatment. Dies quickly and depending on size will fall over within 3 months, others take a year.