A Tall Tree Tale

Riddle: A boy is five feet tall and records his height by hammering a nail in a tree and carving his hame. Five years later he returns to the same tree and finds that it has grown on average 16 inches per year. How high now, is the nail from the ground?

Answer: It is still five feet tall because only the top of the tree grows. The trunk only gets bigger by circumference.

Source: https://www.riddles.com/index.php/3186

A boy is five feet tall and records his height by hammering a nail in a tree and carving his hame. Five years later he returns to the same tree and finds that it has grown on average 16 inches per year.
How high now, is the nail from the ground? — A Tall Tree Tale by don orr v1.