dirt digger-
Unfortunately, what you're showing there is a little bit of live growth on some tiny, mostly dead culms. Over time, it should do well and grow into a mature specimen. However, for purposes of identification now, if you had a picture of the mother clump where these came from (including some closeups to show culm detail and branching pattern), it would be easier to try and identify it. In your Zone it probably is a clumper, but you should be aware that some runners do sometimes bunch like clumpers, so pictures would be a great help. I'm not trying to be unhelpful, but there are about 1200 species of bamboo, and, from the pictures, I can only narrow it down to about 100 or so.

As for your black bamboo, there are black runners and black clumpers. When you say you have "pieces" I'd like to know what you mean. You can't propagate black runners from stem cuttings: you need to make a division by digging up a decent size chunk of rootball. You can use stem cuttings to propagate clumpers, if you know what you are doing; however, you will get the best result and the best growth if you instead take a division of the rootball.

Thanks kudzu9. OK, will try to get some pics of the parent plants this weekend. Oh dear, I didn't know there are black runners as well.
"Pieces" = 1 long bamboo cut into sections. I was told that shoots might sprout from the joinings (u know, like middle of H) and I had to water them by filling the hollow center of each piece. Is that right?

dirt digger-
Most of my experience is with propagating runners. I don't exactly know what you're doing with the stem cuttings, or if the pieces are too old to sprout (if they are, indeed, from a clumper). So I don't know if you have a chance to be successful. I've included a link below to a propagation discussion that may give you some info.

Here is a link that might be useful: Node propagation