'codes' (texture codes) or 'names' (texture class names)
simplify
Return 12-class factor levels (TRUE) or 21-class factor levels (default: FALSE)? The 12-class system does not separate sands, loamy sands and sandy loams into sand fraction variants (e.g. "very fine sandy loam" in the 21-class system is "sandy loam" in 12-class system)