Bill Neill recognizes it as Laetiporus cinncinatus heat and/or drought afflicted in its early stages.
It might be also be an underdeveloped Berkeley's Polypore as shown on Roger's web site in this picture at bottom left
http://www.rogersmushrooms.com/gallery/DisplayBlock~bid~5671.asp
Click on the picture to enlarge it.

About 6" high

Top of "cap"