Thinking about planting evergreen bamboo as a privacy fence. It grows 18-30 feet high and is fast grower. Here is a neat read about controlling the plant http://www.wikihow.com/Control-the-Spread-of-Bamboo I havent measured it out yet but I might need 40 plants <a></a> http://www.gurneys.com/product/hardy_evergreen_bamboo/shrubs-and-hedges
Be very careful with bamboo. You might want to keep it contained. It spreads through root propagation and it's very invasive as it's not native to the US. It can and will choke out other plants and take over your yard if you don't keep it under control, and it's very hard to remove once you've planted it, much like Comfrey.
Just ordered 14 plants and will order another 14 next month. They should all ship out together in March. I also have a 50% off coupon code to Gurenys CODE 05439537 I read up on controlling the plants and I think I'm going to go with a small ditch filled with sand. Then hack away the roots whenever need be. I'm also spacing them out at 5 feet. I'm not sure yet how wide I'm going to let them grow. I have 15' of room to work with between my fence and the road.
try putting them in raised boxes if possible. That way you can seal them off. Cutting at the root's really won't cut it. The runner's will take over your garden space