Crossbow will not work on bamboo. This link details some possible solutions.

Here is a link that might be useful: bamboo control

If your friend just had the bamboo sprout recently, It probably came from some canes that got thrown on her property. If it didn't get a good start, it should be easy to eradicate. This stuff is really easy to propagate. While working for an aquatic nursery, we would cut down large canes and throw them in a nearby pond until they grew shoots from each node. We would then just cut at each node and pot-up for customers. Bill