A young woman asks her mother, Mom, how many kind of penises arethere?

The mother, surprised, answers, Well, daughter, a man goes throughthree phases. In a man's twenties, a man's penis is like an oak,mighty and hard. In his thirties and forties, it is like a birch,flexible but reliable. After his fifties, it is like a Christmastree.

A Christmas tree? the young woman asks.

Yes, dried up and the balls are there for decoration only.