Awful thorny bushes w/ no berries

[rasman]

We too have had to deal with these in the past!
Ya gotta dig! Get all the roots out. You may have to repeat to get 'em all out but eventually they'll be gone. If they're not near any other desirable plants, pour some salt over area after you get as much root out as possible.
There is no substitute for good ol' elbow grease! Getting dirty is good! Its about a relationship with the aina.