What about just cutting the blackberries back?

We are doing that,but hard to get in under walnut tree and we are going to have to move everything forward so we can mow around back of patch.

I had heard that not much would grow under walnut trees unless it was in a pot, hmmm. I will have to remember that raspberries are a posibility next time this comes up. I agree with BBOy that cross bow would be drastic. The thing with blackberries is to cut the canes and when you can remove the roots. like all plants they must have sun on the plant to get nourishment through Photosynthisis to survive. I cut them down to about 5-7 inches, just enough so you can see which is which, and then dig the roots as I can. You will be suprised how quickly perserverance will show results. I am very biassed on this, but if you use a chemical, no matter what they say on the lable, its there, and you are going to eat something that comes from that area. not just you, but the birds, and everything else that creeps and flys. you will still have to cut and dig even if you use the poison, so why not just cut and dig in the first place. I have had this happen, as my neighbor on the back fence is a wierdo and doesnt prune his blackberry grove, which affects FIVE neighboring lots. most of us have been successfull with non chemical intervention. Just dont let them get long and tip root, and you should be ok. good luck, and dont be discouraged

I know this is a problem in a garden, but I love the blackberries growing around. I still have blackberries in the freezer from last summer...

Right now have red raspberries growing across the path from black raspberries, I know they are too close, but don't have much space..

lately I wonder if some of the new stalks in the black raspberry area are red raspberries that dug under, they seem to come up everywhere in a 3 foot area .

They will probably kill the black raspberries which I like a lot... How to tell ???