Thank you, Choronr.
The vegetation was an imported fern. Yes, I can see the problem now: the fern growth at the right and at some distance from the camera is almost the same size as the fern growth directly in front of the camera. Should have used two population objects.
I was trying to create a sense of closeness, i.e., that I was right behind the ferns BUT now that I think on it, if I was that close, the formation should have been much larger. So, the veggies overall should be smaller.