Quercus alba

I have been studying a funny-looking growth on one of my white oaks this spring. Now, I'm no master gardener, but I do know a few people who have taken plants pretty seriously, and none of them know what the growth is.

So I have sent the question to the local extension master gardener to see if my oak is coming down with something. The growth looks like a flower (fluffy white with red specks) and is about the size of a golf ball, but I haven't seen this in the ten years I've lived next to this tree. (I thought we knew each other!)

Quercus. Hmm, I wonder if that's allowed in Scrabble. Want to take a swing(ed) at that, SuperRookie?