How does the dragon describe how long he has been in the forest?

From the text:

“Well,” Minli said, “how long have you been in this forest?” The dragon thought hard. “A long time,” he told her. “I remember when a bird flew from the sky and dropped a peach pit onto the ground. I watched that pit grow into a tree and the peaches fell from the tree and more trees grew from the pits of those peaches until it became the grove of peach trees that the monkeys have now taken over.” He is very old, Minli