Fender uses swamp ash usually. There are 2 types of ash - northern tree and southern swamp. The swamp is a more "white" in appearance but when doing a Mary Kay for instance - its white tinted nitro and it makes zero difference which ash in under it.
Swamp ash grows come from water logged trees. As a result when dried its much much lighter than Northern ash which is basically the exact same wood but grown and haversted above water. Thus is much denser and much heavier.
Some people like the northern for sustain. Most prefer the swamp for the light weight. Swamp will be warmer Northern will be snappier in the maple direction.
I just got some of the best swamp I've ever had. Bodys under 3.5 pounds. I have one that is 3lbs 2oz. Now thats a record breaking light strat body.
According to wikipedia "white" ash is northern ash. Nothing wrong with northern ash but its tough to get a northern ash body under 5lbs. In the 70's that was cool. Today its the lightweight trend.