We had bamboo at our old house, which had spread along a steep slope from neighbors two doors down. The slope was steep enough that we couldn't use machinery to dig out the rhizomes. What worked for us was to cut down the stalks at the base, then brush full-strength roundup on the stump with a paintbrush. Then, every time it sent up a new stalk, we waited for it to get to full height in order to use up as much of the stored food in the rhizomes as possible, then cut it right before the leaves opened and repeated the roundup treatment. We couldn't eradicate it because a lot of it was not on our property, but we were able to hold it back effectively.