I play this one using G chords capoed at the 4th fret so the effective key is B natural. In this post, I'll use numbers instead of chord names so it isn't tied to any particular key. (Tonic=1, subdominant=4, etc.)

  1                  4          1 
  Once in my youth I stood on a mountain,
                   5            1
  And planted some pines in the sand,
              4            1 
   Every day I looked their way,
                  5    1 
  I just couldn't understand,
           5                 4                   1 
  Why they never grew like I thought they should do,
    2                        5 
  I just couldn't understand why,
           1                   4          1 
  Now I've rambled around this whole wide world,
          5             1 
  Today I just happened by. 
   
  (chorus) 
  1                4 
  Tall pines, tall pines, 
  1                   5 
  Reaching up for the clouds, 
       1           4 
  Tall pines, tall pines, 
       1                5       1 
  I'll bet you wouldn't know me now.
   
   
  I'll never forget the morning I left, 
  The hum of the bees in the hay, 
  The farther I walked the harder they talked, 
  How silent it seems here today, 
  There's that old rail fence that we built inch by inch, 
  Surrounding the old family grave, 
  And there's one grave stone standing all alone, 
  Waiting to join me in the shade.
   
  (2nd chorus) 
  Tall pines, tall pines, 
  Reaching up for the clouds, 
  Tall pines, tall pines, 
  I'll come home to sleep beneath your bough. 
  

I learned the song from the album "Father and Son" featuring duets by Bill Monroe and James Monroe. If chords seem to be coming in late as I've presented them, it's because there are transitional runs leading into the chord change. I'm making the assumption that anyone wanting to learn the piece is comfortable in the bluegrass genre.

Have fun,

- Mark