The effect is cool and I like the desaurate look and how the tree is all black and not included in tiling. The black at the top is an interesting idea and I think could really add to this imge if myabe it had some sort of gradient transparency or something leading to it. Right now it looks a bit out of place.
Interesting pic. I'm not terribly fond of the tiled look, and the angle makes it feel as if the picture was cut in half. But the lighting is good, the colors aren't too bad, and the subject material is nice.
Keep experimenting. That's one of the most fun ways to figure out what works in photography. Keep it up!! = - ]