Procedure: We will observe the color pattern and physical differences of 3-5 separate species of trees every 3-4 days. We will then chart and graph our data based on our observations and research of the physical properties of these trees.
Research: We will research the physical make-up of the leaves and root structure of each type of tree.
The article written by March Archetti, "The Origins of Autumn Colors by
Co evolution", is about the reasons as to why leaves change color. He mentions three main reasons: the pigments in the leaves change their structure, the synthesis of new pigments in autumn, and the coexistence of insects. A large portion of his article is discussing the strategies in which trees will produce brighter, stronger leaves.
The amount of pigments (which effects the color) in a tree depends on the particular tree, the soil acidity, and the minerals in the soil. Weather throughout the fall season has much do about the color in trees. Cool nights destroy chlorophyll while freezing temperatures inhabit the red pigment.
This article explains the process by which the chlorophyll replacement rate in leaves slows down starting in the fall. Every tree's chlorophyll rate is different and that causes their leaves to change colors at all different points. Eventually, the leaf is pealed off from the branch and the green chlorophyll fades into different pigments that cause the bright colors.
The changing color of leaves is not due to a colder climate, as many people believe, but rather to the shortening of the amount of time that the sun is out as the season progresses. Individual colors that the leaves may change are due to the chemical complexes in the tree and surrounding soil. Fallen leaves are not useless; in fact they enrich the soil, and help keep everything that grows in soil, such as trees, alive.
The article "Fall Foliage Guide,” describes the cycle of chlorophyll in a plant and how it relates to the changing of leaf colors. In certain autumn conditions leaves tend to produce different colors and also when the leaves are either exposed to sun or protected by shade. The remainder of the article described the leaf colors of various types of trees.
Return to the Topic Menu
IMPORTANT: For each Response, make sure the title of the response is different than previous titles shown above!
Weather & Earth Science Resources
Tropical Ecosystem Courses
Tools & Other Stuff