Won't take long for me to tell you everything I have learned about them in the past two years or so since I started hunting them:
1. They're a lot harder to kill than I figured they would be
2. I still ain't got enough sense to figure out how to kill an old one yet

Jughead your go to guy for big buck info?

I've used round up on them with some success around the house. Not the pre mixed kind though, just mix it a little strong.

Jughead, jug's dad, and T123Winters so actually that's a pretty strong panel of experts. I ought a have seven or eight killed by now that would make book if I listened better I guess.

Agree with folks who say deer eat them regularly. Have seen deer eat their way through a whole bottom of em... going from one to another gobbling leaves. Hung stand today overlooking some - bad acorn crop this year.