[header] How to control the spread of bamboo [title] Dig a trench around the bamboo. [step] Dig a trench that is 28 inches (71 cm) deep. The trench should be at least 2 feet (61 cm) away from the bamboo shoot. 
Once the trench is dug, you should be able to locate the bamboo rhizomes growing horizontally under the ground. The rhizomes will look like the main stalk of bamboo growing out of the ground.