I am amazed! Raspberries take over everywhere and everything here. The only things to compete with them are trees, or shrubs. For me, raspberries, and blackberries are invasive nuisances, and they pop up everywhere, you chop them down, and bingo, you just made 20 more!
The only thing about chopping down the raspberries and blackberries, they fruit on last years wood. So, don't destroy it! If you burn the patch, you won't get fruits until it grows some new wood.