In the good old days...if you drove past something like this on the highway, and you were a model railroader, you would have pulled over and leaped out with joy.
Why?
Not too often do you see a field of lichen growing in broad daylight. Yesterday, while driving in New Hampshire, I spotted this on Route 16 and couldn't resist.
That said, I haven't used the stuff on my layouts for over 30 years now, thanks to Woodland scenics and their ground foam products.
Even so, I had to hold some in my hand and pretend it was 1966, and my barren layout was about to become "King of the Forest."