Thank you all...

@landorl - After looking at I again, I agree with you the walls need some work. Those are not really towers - not sure of the actual term here - but they are a sort of emplacement that bulges out from the wall near the top.

@ravells - The hedge mazes... Ifound a simple maze image and brought it into PS, traced the 'walls' with a bright color (yellow) solid brush of 5 pxls (adjust depending on your scale) then selected the yellow, inversed and deleted everything else. Dragged it onto a layer in my image and applied a pattern overlay, some noise and a gaussian blur (again subject to your scale), Voila - Shrubberies!!!!

@Ascension - The scale is 1pxl = 1 foot @ 100 pixels/inch (map size is 3000x3000 pxls)