To know exactly, a certified experienced arborists can us a a couple of newer tools to "look" inside a living tree. One is called a resistograph, the other, sonic tomography.
Using longtime residents and historical pictures is another way if complete accuracy is not needed.
There is a white pine in N. Carolina that is 227 years old. http://www.treesforme.com/il_pinus.html suggests 200+ years old