Does it spread?

I've just looked it up in my RHS book and it says that the height is up to 8' or more, and the spread is 'indefinite'. It also says that it has 'running rhizomes'. All this to me means that the answer to your question is 'Yes!' Looking at the photo in the book, it's a beautiful Bamboo. Have you got one in your garden?

Many thanks for your reply. Certainly looks as if we might be wise to use a root barrier when we get round to planting our specimen, which is still in the pot in which we bought it, some weeks ago.