The effect is watercolors is it not? The continuation of the style from the original scan is nicely done.
One thing I do notice, though, is that the outlines in the green leaves are not as coherent with the rest. If you look at the tree trunk from the original scan, the outlines are very blurred and undistinct, while the ones you made are sharp and clear. Perhaps if you blurred those lines a bit to mimic the scan a bit more, the effect in that particular section would be achieved better.
However, the overall quality is high. The maintenance of the color theme and the continuation left from the scan is quite seemless in general. Well done!
