If you have had a great deal of rain lately, my guess is that the white spots are a fungus of some sort. I would wash them off with some mild soap, then dry them thoroughly and put thm in the sun for a day or so. Be very careful this winter that they do not become infected again.
If you have a funguside I would use that in place of the soap. Good Luck.

Hey Scott,
I am glad someone finally answered your post. Sometimes it can take a while but not as bad as the aquarium forum. You see the same post on page one for weeks, with no action.

Hello Scott-

Me too. Had some sort of soil fungus which ate up an entire crop of dahlias this summer. It was tres bizarre as the flowers seemed to die from the bottom up and the flowers were stunted yet when I dug up the tubers they were solid as a rock and appeared to be fine with the exception of those white nodules. Just glad to hear I am not the only one. Excellent shots btw.