Vachellia Farnesiana

Obviously, I had to look up the name of this tree—I am no botanist. At least, I'm pretty sure this is the name. Please correct me if I'm wrong. Here is a web site that seems to support my conclusion, as well as the Wikipedia article where I got the alternate name:

http://www.wildflower.org/plants/result.php?id_plant=acfa
http://en.wikipedia.org/wiki/Vachellia_farnesiana

I took these using the inverted 50mm lens trick. I haven't done any macro photography in quite some time. I was walking Bawoo and these caught my attention as a perfect subject.