ONE OF THE most beautiful shows of nature in the United States is the changing colors of the leaves in the autumn. The trees in the New England and mid-Atlantic states put on such a spectacular display that tourists come from all over the country to drive along the country roads, enjoying and photographing the deep red, orange, and yellow colors of the leaves.

The changing and falling of the leaves is a natural process. As the days grow colder and shorter, trees begin to prepare for the winter months. The leaves on the trees are food-making factories, and to conserve energy, the trees begin to shut them down. During the winter there is not enough light or water for the leaves to create food. Instead the trees will live off the food that they stored up during the summer. As these leaves die...