Question: Please review the attached pictures of a Arizona Ash (Fantex) a homeowner has asked us to look at. This is a 20+ foot tree, free flowing, there are no constraints on the limbs and this limb was about 6 ½ feet into the tree. This homeowner has 2 of these trees and both trees have had limbs like this. Can you tell us why this tree limb did this, and what is going on with the tree?

Answer: The condition is called fasciation. Some herbicides will cause such growth abnormalities. I see it occasionally. Prune it out, and it will probably not come back.
Or, leave it as a conversation piece. Here are some web sites with additional information:

http://www.rhs.org.uk/advice/profiles0700/fasciation.asp, http://en.wikipedia.org/wiki/Fasciation.