DOCTRINE OF USUFRUCT, THOMAS JEFFERSON

Certainly I am no laywyer, but I have plenty in the family and can thus dig through a few legal terms here and there, so when I came across the Term "Usufruct" I was intrigued. So way back when we were setting up our country and constructing our government the term Usufruct was going around and it was basically stating that there is a LAW, that the current generation has both a legal and a moral obligation to future generations, IE what we do now effects those that come later and legally we need to be responsible. So what are we doing to set up our children and theirs when it comes to our wilderness and our environment? What did our great grand fathers do for us?