I really dont want to use weedkillers if I can avoid doing so. I am going to try to mattock the whole area to try and remove as much of the rhizome clump as possible, following which I will see what grows and take it from there.
Some local treatment may be unavoidable, but have decided not to start from that point without trying other things first.
Read up on your bamboo , it can send out runners underground that emerge many yards away up to seven years after the main plant has taken root .
Use a petrol powered brush cutter to hack it down to about 2 inches tall , clear the ground of everything & burn it as soon as it becomes dry enough .
Then weed kill it with agri strength round up as it reemerges showing new four inch long shoots ,
You'll also have to do it several times cut as soon as it gets to the four inch height again cut it , clear it off , burn it & repeat the weed killing exercise till you get a year without any new growth showing .
Allowing it to part regrow to four inches high is thought to put the plant into a more, " Susceptible to being weakened by frequent cutting & Round Up kill mode" .
It's the only effective way I know of killing it off entirely
Most places that sell the half inch plus thicker bamboo recommend you put down a heavy duty polythene sheet /civil engineering barrier 1.5 to 2 mtr wide & just as deep , some 3 mm thick & make sure you overlap & seal up the joint by a couple of feet .
Re using a mattock .. that's fatal ..... a sliver with a growth node on it will regrow into a new plant , it's like couch grass or comfrey in this respect.