Given the almost lack of annotation in those examples, you might as well render the views and use photo-editing tool to place your trees and put those behind an elevation with only the annotation that is there.
The coloured vectorial elevations use such a limited palette / penset of colours, the trees would be the least of my worries. In my experience I can't even get near white surfaces to not be a shade of grey that is way too dark.
If you want a good way to scale the ortho rendered views in 3D: put some morph lines as a 'frame' on each elevation axis, you can select them in 3D and zoom to them to get a pixel perfect represenation of an excact measurement in your model.
Erwin Edel, Project Lead, Leloup Architecten
www.leloup.nlArchiCAD 9-26NED FULL
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