To Everyone

I am a newbee to this fly fishing game and I just learned a year and half ago that the state of Tennessee stocked fish in different rivers. I need for someone to please explain to me how to tell one from the other, so when I catch a trout I will be able to say this one was from the hatchery and this one is a locale born fish. To me a trout in the river is a trout in the river. Thank you for your time.

WayneC