When an owner of a dog takes it for a walk, bags up the dog shit and throws it into a tree where it proceeds to dangle from the branches, therefore producing shit trees. Usually found in rough estates around the UK.
An author’s little-known truth, because trees give rise to lumber, which can then be converted to paper, before it is being used to print books, which earn the writer a cash lump sum or an obscene royalty.
In billions of homes, it’s not uncommon for parents telling their children off that money doesn’t grow on trees, or that money is hard to come by, but for millions of authors and publishers, the opposite is true: “Money grows on trees.”
To be so concerned with specifics or details that the larger problem, situation or point is missed. Alternate: can't see the woods for the trees. Often said incorrectly as "can't see the forest THROUGH the trees." (English, circa 1500's)
A: I hate the piss and crap all over the place from my wife's cats!
B: Dude, she only has the cats because she knows you hate it and is trying to drive you out. I guess you can't see the forest for the trees.