Only 6% (24 of 396) participants noticed money hanging on a tree, when focused on the cell. But they bypass a  tree without any problem.

Hyman Jr., I. E., Sarb, B. A. & Wise-Swanson, B. M. (2014). Failure to see money on a tree: inattentional blindness for objects that guided behawior, Front. Psychol.,