Inserting a new sky usually works well to use the
Darken Layer blending mode. This makes masking easy,
and often not even necessary with the dark foliage.
I only needed masking in the light areas of the buildings.

Cleaned up the red and cyan fringing with Hue/Saturation

forum discussion: http://forums.dpreview.com/forums/read.asp?forum=1006&message=22548111

original image by BrianRu: