The lighting is a bit harsh and really masks a lot of the depth that the bark of the tree would otherwise add to the image. I like the processing overall.
I love the texture here. I agree with ordinaryangel that the left side is a bit too dark. A tighter crop around the know would have probably worked better for me.
I agree - nice contrast and texture. If it were me I might've cropped to only have the knot and some texture as I find the left side to be a bit distracting may be just a me thing though.