Linda From Maine wrote:
You're right, not the title, the intro in which you said where shot.
I guess I just think of vertical rock faces as more interesting and challenging for plant growth than weeds on a city sidewalk. Sort of like people think of weeds in general, compared to flowers.
And the personal experience thing comes into it: I have seen and photo'd cool little trees growing out of the sides of boulders in the Cascades, but wouldn't likely look twice at a dandelion in a cracked sidewalk :)