Deciduous Trees Draft 2

This topic submitted by Kyle Coburn ( coburnke@muohio.edu ) on 10/11/04 .

Natural Systems 1 Syllabus---Western Program---Miami University

Mike Litchfield
Kevin Leciejewski
Kyle Coburn
James Myers

Student Generated Lab

Introduction:

Throughout this lab the rate at which leaves fall from deciduous trees will be studied. The purpose of this lab is to determine the characteristics of leaf fall between six different native trees. Through the lab, a better understanding of the trees that thrive in our environmental region will be obtained. The hypothesis is that trees within a species will drop their leaves at the same rate and time. When comparing different species, the rate at which leaves will fall will differ. It is hypothesized that the trees that hold their leaves the longest will have the quickest rate of leaf fall. The research question that will be answered is: What is the relationship between the rate at which various species of deciduous trees drop their leaves? It can be predicted that trees within a species will drop their leaves at about the same rate at around the same time. In this lab, it is planned to accomplish a detailed study of various trees in regards to when they drop their leaves and through this data a better understanding of the characteristics of various trees will be accomplished. This research is interesting to the group because trees are an important part of our environment and people come in contact with them every day. In the fall, the color of leaves is a very beautiful transition and through this lab out knowledge of this transition will be better understood.

Background Information:

Deciduous trees are an essential part of the Ohio landscape. All of the trees selected (Sugar Maple, Ash, White Oak, Red Oak, Tulip Popular, Gum) are native to Ohio and prosper in its environment. Due to the fact the lab studies the rate of fall of leaves, it is essential to understand chemical and physical reasons why leaves fall. Deciduous trees drop their leaves in order to survive the lack of energy supplied during the days of winter and the region's harsh climate. During the winter months, there is a lack of light and water used for photosynthesis. Without these elements, the trees leaves are useless therefore taking much needed energy from the tree. As a result, the tree discards the leaves to conserve the energy. Also, Deciduas tree are equipped with buds that aid the tree in surviving the winter months but to expose these buds, the leaves must be discarded. The bud protects the tender leaf tissues needed to regroup the leaves in the spring. There are many chemical reactions that cause the leaves to change. In certain leaves carotenoids are present throughout the year. Carotenoids provide the yellow, orange, and brown colors. During the summer and spring months, Chlorophyll (green color) dominates the leaves chemical makeup and photosynthesis process. But during the fall, due to cooler temperatures, the chlorophyll retreats leaving the Cartenoids. Thus resulting in a change in leaf color. In trees that turn red during the fall months, anthocyanins are produced and replace the chlorophyll.

Literature Review:

Cooperrider, Tom S. The Dicotyledonae of Ohio. Columbus, OH: Ohio State University Press, 1995.

We chose this book because it was a technical aspect of the change in leaf color. It helped us note the chemicals involved in the color change of the leaves. It was used because of its technicalities.

Dean, Forest W. Deciduous Trees of Ohio. Columbus, Oh: Ohio State University Press, 1984.

We selected this book because the various characteristics of leafing patterns we are looking for were explained in the text. This helped us hypothesis that the leaves that hold their leaves the longest will have the quickest rate of leaf fall.

Dean, Forest W. Ohio Trees. Columbus, OH: Ohio State University Press, 1970.

This gave an explanation for our trees in the area of study. This book discussed in length the deciduous cycles of Ohio trees.

Elias, Thomas S. The Complete Leaves of North America. Portland, Oregon: Timber Press, 1980.

The book explained the chemical process in which the leaves change colors and why trees lose their leaves when they do. We used this book to help us get an understanding about why weather affects leaf fall.

More, David and John White. Illustrated Encyclopedia of Trees. Portland, Oregon: Timber Press, 2002.

This book shows the leaf types used in our project. This book gives great illustrations of the branch structures and leaves of the trees that we are studying. We used this book to correctly identify the trees we were analyzing.

Fergus, Charles. Trees of Pennsylvania and the Northeast. Mechanicsburg, PA: Stackpole Books, 2002.

This book talked about the trees native environments and what conditions the trees live in. It specifically explains buds and regrowth. We used this to estimate which trees would fall first based on where the trees came from.

Whiteside, Thomas. Defoliation. New York, NY: Ballantine Books, 1970.

This book discusses the leaves on the trees in question. It gives great explanations of how the surrounding areas affect the rate of leaf fall. We used this to see how our weather this year will affect our precious trees.

Gregory, R.P.F. Biochemistry of Photosynthesis. Chichester, NY: Wiley, 1989.

This text discusses chlorophyll breakdown within the leaves of the trees. We learned much about the leaves using this text and it helped explain why leaves fall when they do.

Halliwell, Berry. Chloroplast Metabolism. New York, NY: Oxford Press, 1981.

Photosynthesis is the main point of this text. It explains what happens throughout the seasons with the trees getting the nutrients it needs. The fall is obviously the season of interest for our experiment and this book described this season pretty well.

Lanner, Ronald M. Autumn Leaves: A Guide to Fall Colors of the Northwoods. Minocqua, WI: Northwood, 1990.

Discusses the leaf fall in deciduous forests in the Midwest. It contained descriptive images of the colors of leaves in our area of study. This book gave individual descriptions of some of the trees we are studying.

Lee, David W. "Pigment Dynamics and Autumn Leaf Senescence". Ecological Research v.18 Issue 6, 2003, p.677.

This book talks about the chemistry in the trees in our study. This chemistry helped describe the processes the trees go through and how the leaves affect the trees.

Pirie, N. W. Leaf Protein and Other Aspect of Fodder Fractionation. New York, NY: Cambridge University Press, 1978.

This book gave us a perspective of a time scale for the season of autum.

Online Sources:

http://photoscience.la.asu.edu/photosyn/education/colorchange.html

This website was a basic children's website titled "Why do Leaves Change Color in the Fall." This really helped us get a basic understanding of why deciduous trees lose their leaves.

http://www.na.fs.fed.us/spfo/pubs/fs/colors/colors.htm

This is a website put out by the United States Department of Agriculture and has detailed information about leaf fall. This website gave us more of a detailed understanding of what the first website talked about.

http://nasw.org/users/sperkins/fallleaf.html

This website described pretty much the same as the other two but gave some different information necessary for our project.

http://www.esf.edu/PUBPROG/BROCHURE/LEAVES/LEAVES.HTM

This website gave us a good description of the chemical processes that the trees go through. Leaves change color because the trees are taking the nutrients made by the leaves and this website taught us this.

http://www.madsci.org/posts/archives/sep2001/1000876977.Bt.r.html

This website taught us why leaves from deciduous trees lose their leaves regardless of climate. This website just adds some information not found in other websites.

Research Design:

The experimental design of this lab began by selecting six of the most common native deciduous trees. These trees are: White Oak, Red Oak, Ash, Gum, Tulip Popular and Sugar Maple. Five individual trees within each species were then selected from the surrounding region. Under each of the sample trees, five one meter by one-meter plots were marked by spray-paint in the corners of the plots. The plots were selected at random. Within each plot, the number of leaves that corresponded to the tree were counted and recorded and the date was noted. Data will be collected every other day until the leaves have completely fallen. By counting the leaves, a quantitative value can be placed to the rate at which various trees drop their leaves making it easier to determine the relationship between characteristics of various trees.

Materials and Methods:

This lab contains a very limited number of materials that must be used. Spray paint was used to mark plots on the ground surrounding the tree and mater sticks were used to create the dimensions of the plots. Microsoft Excel was used to organize the data collected. To involve the class in the study they will go into the field and collect that data needed for each of the selected trees simply by counting the number of leaves that fell in each plot. All of this data collected will then be combined to further aid the research.

Sample Data Table:

TREE: DATE:

Plot 1 Plot 2 Plot 3 Plot 4 Plot 5
Tree 1
Tree 2
Tree 3
Tree 4
Tree 5

Research Time Line of research execution:

9/23/04 Research idea proposed
9/30/04 Selected trees to be studied
10/4/04 Marked plots around tree
Began collecting data
Data will continue to be collected every other day until all the leaves have fallen.

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