How big are the clumps? If they are large you may want to divide them. You can cut though the clumps with a chain saw or saw zaw if they are large enough.Then get them out with a shovel. Cutting of clums or canes that are a year or two old may work.
Frank

Honestly it depends on the how much work you are willing to put into dividing the clump. Even large, open clumpers can take a few hours of work by more than one person to divide.

As for propagating it, there are different methods that work for different species. If you had some pics of your boo it might be easier to tell you what method to try. The two most common methods are using single node culm cuttings and whole culm burial, but again not all bamboos will take root this way, and either way it will be a few years for the cutting to reach a sizable screen height.

If you are wanting instant screen you might want to look into purchasing some larger divisions.

Here is a link that might be useful: My Bamboo