Source: Player's Handbook v.3.5
You can follow the trails of creatures and characters across most types of terrain.
Benefit: To find tracks or to follow them for one mile requires a Wilderness Lore check. You must make another Wilderness Lore check every time the tracks become difficult to follow, such as when other tracks cross them or when the tracks backtrack and diverge.
You move at half your normal speed (or at your normal speed with a -5 penalty on the check). The DC depends on the surface and the prevailing conditions: (Very soft - 5; Firm - 15; Soft - 10; Hard - 20)
Very Soft Ground: Any surface (fresh snow, thick dust, wet mud) that holds deep, clear impressions of footprints.
Soft Ground: Any surface soft enough to yield to pressure, but firmer than wet mud or fresh snow, in which the creature leaves frequent but shallow footprints.
Firm Ground: Most normal outdoor surfaces (such as lawns, fields, woods, and the like) or exceptionally soft or dirty indoor surfaces (thick rugs, very dirty or dusty floors). The creature might leave some traces (broken branches, tufts of hair) but leaves only occasional or partial footprints.
Hard Ground: Any surface that does not hold footprints at all, such as bare rock or indoor floors. Most stream beds fall into this category, since any footprints left behind are obscured or washed away. The creature leaves only traces (scuff marks, displaced pebbles).
Special: A ranger receives Track as a bonus feat.
This feat does not allow you to find or follow the tracks of a subject of a pass without trace spell.