I've been trying to control the buckthorn on the berm, but it is a real struggle. The above is a buckthorn bush a year after it was cut back. It came back with vigorous growth. Even when I cut a buckthorn down to a stump it will quickly create a little bush from the stump. But eventually it can be killed with consistent attacks with a pruner. The stick in the picture below is a buckthorn I have shorn of any greenery about a dozen times and it looks like it has finally given up.
When I do remove a mature buckthorn bush though, it can just create good conditions for a million buckthorn seedlings to spring up. So now instead of attacking all of the mature buckthorn bushes, I am selectively targetting the females that are easily identified by the black berries. I also take out isolated buckthorn seedlings. Where there are large numbers of buckthorn seedlings (ie. where a female buckthorn was recently removed), I let them be, as I don't have the patience to clear them out completely and eventually one of the seedlings in a patch will shade out all the others anyways.
