this is perfect example thinking outside of the box, many thanks. I guess playing with faces material id (instead of Edit Mesh modifier) would work as well.
But the perfect solution would be 2 important* options:
1) Implement
layer objects as reference
2) Option to turn forest off if reference\surface layer is off
*- it also makes possible automatic scattering (replacing) when user reloads dummies from other applications (autocad\sketchup blocks sitting on separate layer).
I wanted to request this feature before this post, but now I see that
'layer as reference' feature would help to solve item's visibility problem in the current view. all is needed is to temporally put dummies\surfaces on some !!_TempHidden layer and save it in Scene State.
Are those 2 options doable?