I guess this is an example of the old saying, "everything is relative".
By preview measurements most of these stones measure 2.5 to 3 Terragen meters wide and yes the branch could easily be a full dead tree at 8 Terragen meters from base (hidden) to tip.
These big items most likely are what throw off the eye/brain evaluation as well as the camera angle and DOF which may indeed give the render some (wasn't intended) tilt shift "looking at toy models" effect.
Offsets, scaling and tallness inputs (PFs) are used which alter the base fake stones, stone colors are from merged PFs.
Oh and that violin isn't quite pristine, there are some visible spots from a dirt layer, I hope it's not a Stradivarius.