All you can do is keep cutting them back and dig out the roots. They are persistent blighters.

is there any chance you could dig in some bamboo membrane into the soil around your perimiter . personaly i would have a word with the neighber a friendly one and let them know whats happening they mite help but dont count on it.then you can dog up as much of yours root and all and bin or burn it .pour one or 2 of them central heating bags of sea salt generasly over the offending area and cover same said offending area with thick black polythene . you will get on top of it in the end . if it is high and hard to deal with now ie its tall and thick . you know a bit like gorden brown lol then rent a petrol strimmer for a day with a petrol engine and a cutting blade and butcher it down to the ground .then do the salt and black polythene thing .i hope this hellped take care bye for now .
ps if your neighber isnt so friendly and helpfull remember that his plants over your garden boarder are his plants and i believe bye law you have to give him any of them .

To deal with the ones you have growing in your garden currently, the only efficient way is to reduce top growth, dig around the base, locate the knobbly, woody bulge at the bottom with roots going down off it, drill into it with a medium wood bit (not right through, just to penetrate the wood) 2 or 3 places, depending how big it is, then apply SBK, cover with something (I usually use old flowerpots) and replace the soil. And don't plant directly into that spot, leave the root with its flowerpot in situ - if it regrows, treat again in the same way. With the inverted pot over it, at least you can find it again easily. Smaller brambles that haven't long been rooted can be dug out, but make sure you get all the roots. And thereafter, keep any eye out for any fresh invaders, they're much easier to deal with if they've either only just germinated, or only just rooted at the tips.

i guess most weeds or invaders are best got at young realy hay bamboo ?

Yes Nosey - you know what they say about a stitch in time...

ofcourse just because its just a tiny little flicker of a flame miles away in the hills doesnt mean you can leave it . you must rush up there and put it out or it will be huge bye the time it reaches you.i think the membrane for the nieghbers is valid 2 .

Huh - sorry NP not sure what you are saying...

pull the little weedfs out now rather than weight till they are huge triffids however small the weeds mite seam .

It was the membrane for the neighbours that confused me... never mind lol

ow sorry your confusion wasnt obvious moon grower .if the brambles are starting next door then if you stop them getting in under the fence then thats a big part of the battle is all.

Thanks all
unfortunatly the neibouring land is derelict so no help from there The bamboo membrane sounds a good starting point and then just keep tackling any that show thier heads so to speak by digging out. I'll let you know how I get on I'n also tempted to try Noseypotters idea of sea salt and polythene over the other side of the fence, afterall it would be doing the land owner a favour wouldnt it

its worth a go stuck and its cheap