Red oak tree in Texas has hard, gnarly growth on trunk and branches. smooth branches where it hasn't reached.

Question:you can scrape growth off, but it isn't easy. don't even know if you would call it a growth or a fungus or what.

Answers:
I'm not sure if it effects red oaks, or if it is present in Texas, but it sounds like Black Knot Fungus. It sounds strange, but if the growths look sort of like dog poop hanging from the branches, then it is probably black knot.