Natural or Not?

When I was walking along in the Alentejo area of Portugal, I looked down and I wondered if I was seeing a real plant, and a real rock. For some reason, both the rock and the plant looked to me as if they had been created by human beings; and were not natural at all.  The rock seemed to have been knitted or woven out of wool, the plants were perhaps plastic, like bottle brushes.

I examined them closely and I found that in fact they were completely natural.

Do you see what I mean about them, or do you just think I have an over-active imagination?