The little knobby things growing out of the ground are called Cypress Knees. They provide a way for a cypress tree to "breathe" when under water. Many cypress trees in north central Florida are hundreds of years old. For the first 40 years, they grow at the pace of a normal tree. But from then on, they grow 1.25 inches in diameter every 47 years! You determine how old a cypress tree is from its circumference, not from its height.