Big pond, why do you say that? One of my dams is completely clay, the other is lined with clay on the pond side. The top of the dam is about 12" road. I don't see how peach trees and pecans on the away side could penetrate the damn. I figure most of the roots will stay at the surface, or grow down at a steeper angle than my dam. The root ball as a rule of thumb is as wide as the drip line, and these trees will not even come close to the road. But if you have a good reason, I want to prevent future problems.
