Trees go through puberty. All organisms have to balance and optimize the energy expenditures devoted to growth, maintenance, activity and reproduction. Growth is essential for a tree in order to reach for the sky and gather sunlight. It is true that trees don't have the same physical activity of a hummingbird or cheetah, but all these organisms, even when at total rest, are expending energy on maintaining their internal systems (this internal regulation is called homeostasis). When growth is adequate and there is enough energy surplus above that required for homeostasis, then energy can be devoted to reproduction. Most trees don't flower until years after germination. An oak, for example, might take forty years to produce flowers and acorns. Our yellowwood should flower about 8-10 years after it started growth from a seed (not from when we planted it).

A yellowwood in bloom can look like a totally different tree than when not in bloom. This is true of most trees. Flowers are the reproductive parts of a tree, and they occur only at a certain life stage and only at certain times of year. Since every cell in the tree has the same DNA, how does the tree manage to control its bloom times? Remember, a caterpillar and a butterfly have exactly the same DNA in every cell. The expression of a certain DNA sequence in a cell of the body is controlled by other regulating DNA that makes what are called transcription factors that tell it when to turn on and turn off. These processes are actively being investigated.