|Paint. Nap. Paint. Nap.|
Some years ago I didn't know what the word ubiquitous meant, but Dean Koontz uses the word all the time so I looked it up.
I think paintings of trees are ubiquitous because they are easy to draw.
Really good artists don't draw trees for this very reason. Take Pablo Picasso, for instance. I'm no art historian, and I only did a quick Google search, but Picasso never drew a tree. Not even when he was young and his mother took him to McDonalds and he drew naked women with a crayon on the paper placemat. Picasso had a distinct aversion to drawing trees. Drawing trees was anathema to Picasso.
Anathema is another word I didn't know when I was young, though I am not aware that Dean Koontz has any special affinity for that word.
To conclude, take a pencil and draw a vertical line. There, you have drawn a tree. Laughably simple. Picasso was right.
Paintings of trees . . . eh.