The oaks in big ed's picture are live oaks. ("Live" is part of their name -- the name of this species of oak is "live oak"). They are common along the Gulf coast and southern Atlantic coast. They are famous for their wide, spreading branches, which if they are not pruned, sometimes reach down to the ground.
Live oaks frequently do have Spanish moss hanging from their branches. This is not because Spanish moss prefers live oaks. Although the wide branches of live oak do provide lots of hanging places for Spanish moss, Spanish moss will hang from a wide variety of trees. The association is because the range of Spanish moss and the range of live oak are nearly identical. Spanish moss needs to live in humid climates -- like along the Gulf and southern Atlantic coasts.
Live oaks with spanish moss would be a real modeling challenge. You would have to make your own armatures, with the green leaves on top and the gray, stringy Spanish moss hanging down below.
When the NMRA National Convention and Show were in Atlanta last year, I went for a day. I remember seeing a module in a club layout with a Louisiana bayou, complete with alligators and Spanish moss hanging from the trees (swamp trees, not live oaks).