Is This Some Type of Fungus?

[PineFever]

Presently cutting some firewood trees about the 6200' level in So Cal.
I noticed this area of scrub oaks that look like they have christmas ornaments growing on them. Not very many on a single scrub oak, sometimes only one but some have three to six or more on them. Can someone tell me if this is some type of fungus, is it harming the scrub oaks? Is it a disease? Spreadable? Any input is appreciated.

Ed
:chainsawguy:

 

[demographic]

Looks like "Oak Apples" to me.

Or maybe Oak Marble Galls but I'l admit that till I just Googled the term Oak Apple I had never heard of the term Oak Marble Galls.