Usually you can tell by the colors. Pines are a brighter green, while hardwoods vary in the shade of green (i.e., different species such as oak, maple, hickory, etc.). Also, since alot of the public land in louisiana is owned by timber companies, you can almost make out unmistakably the rows of pines.

From all topo's I've seen on-line, especially woods I know, pines show up dark green in comparison to hardwoods.