Southwestern Folklore is a skill in Wasteland 2 available only to the game's Kickstarter backers. It is not offered during character creation, and is not required for any mission. In the starting area, Cpl. Solveig Sefors will provide 4 skillbooks that add +10 to the skill, if the player types in the special access code received from inXile's Ranger Center in dialogue. The code is available on this page.
61290 is the code.
It displays additional flavor detail when examining the scenery, entering locations, or passing by points of interest.