The largest of these pines are less than 6" diameter at the base. Most are smaller. We've been in a drought so they are perhaps a little stunted but, I have an aerial photo of the pond taken only a few years ago and there were practically no tree visible on the dam.
So, the trees aren't substantial but they are thick - not too many on the top surface of the dam (which is flat like a road bed because there was an unpaved access road that was used many years ago?) but the front and back sides have grown up in mostly pine and a little privet.
I don't know if this link will work so you can see the aerial view or not but, here it is:
http://qpublic3.qpublic.net/ga_clarke.ht...=242C1%20D099#1