How to Build a Broadfork

For Bert Boyd. I don't know how deep the roots go, but try using slates, placed vertically in the ground around the patch where you want the bamboo. Fibre cement slates are approx 2ft long and 1ft wide so the barrier will be quite deep. I have found this especially useful to contain patches of mint which will spread everywhere otherwise. The bits that do escape are easily pulled up.
Another method would be to plant the bamboo in a container plunged into the ground.

Looks like hard work and would defeat the puropse of raised bed which were mentioned, since to use the fork one would have to walk on the beds.
The raised beds I have are 8ft x 4ft and require only a light forking over and then a till with a three pronged harrow type cultivator and the whole effort takes about fifteen minutes for a bed. The soil is much easier to work as it is never compacted by walking on it.
I constructed the beds using 6" x 2" rough sawn timber and lined the inside face with a strip of dpc material wrapping it under the bottom edge and secured with clout headed galvanised felting nails; this keeps the soil out of contact with the timber. The outside can be treated with a timber preservative if required.
The beds can be placed directly on cleared ground and filled with a mixture of soil and compost or, if converting an existing garden, in shallow trenches, the spoil from the trenches piled in the middle where the beds are to be; add plenty of compost and level off.
Raised beds have the advantage in that vegetables can be 'block' planted, plants planted the same distance apart in all directions - no row spacing needed.
Weeding is easy as well as all parts of the bed are easily reached from either side.
Distance between beds need only be the width required for a wheelbarrow and a plank placed on the side boards of two adjecent beds makes a handy seat when weeding.

Do you have any articles on building barriers to contain the spread of bamboo plants in an urban setting?