THE FACELIFT OF A TREE

2. RELEVANCE OF OUR RESEARCH QUESTION:
We feel our research question pertaining to the peeling of American Sycamore trees is relevant because it would be similar to understand the aging process of human beings. It can be easily understood that bark on trees serves the purpose to protect from physical injury, water loss, diseases, and insect and animal pests. What is more difficult to understand is the idea that with each year of a trees life an additional layer is being formed, that will then be shed. Why would a tree grow, only to peel? This is because the trees do not peel at the rate of which they grow. Normally most trees retain several years of growth to the point where the bark becomes thick before the peeling process takes place, according to Joseph R. Thomasson. In connection to this Thomasson completed a study at the Fort Hays State University dealing with the unique and distinctive patterns as a result of the way different trees peeling processes occur. He found that the Honey Locust tree bark peels in rings. By this the bark peels in many different horizontal rings that cover the entire diameter of specific parts of the trunk. The Paper Mulberry tree peels in long vertical strips. He also found that this tree allows several more years of growth before peeling begins. The American sycamore tree, which has previously been discovered, tends to peel in pieces. Although the peeling begins at the top of the tree while working its way down to the trunk, this tree has no specific order to its peeling.

3. MATERIALS AND METHODS:
To complete this lab we will closely observe the peeling of six different sycamore trees within Miami's campus. All six trees were located in completely different areas, such as the presence of people, other trees, and the elevation level since half of the trees were on hills and the other were on level ground. After selecting the three trees we are going to observe, we came up with the way in which we will observe them. On each tree there have been four specific parts that will be watched, measured, and photographed. These four parts include two on either side of the trunk, and then two on different branches, which are on opposite sides of the tree. We came up with these four spots because we wanted to cover whether more bark peeled from the trunk or the branches, while also taking into consideration whether one side peeled faster than the other side. With a ruler we will actually measure the amount of bark that has peeled from each spot. Then we will take a picture of each of the four spots on the tree, followed by the recording of these numbers, which will actually make up our statistical data. This process will continue to occur 2-3 times each week until the beginning of December. It is then that all of this data will be combined, and that the pictures will be put on a board next to each other so that the numerical statistics and the visual sight of the pealing rate can be seen. Although this process will continue until the beginning of December, we will divide our data, and pictures into each week beginning with Monday and ending with Sunday, so that the weather patterns can be taken into consideration. This way, if it were to rain the day before measurements were taken, the rainfall would still be noted as effecting the rate of pealing. This division into weeks will also allow us to consider the temperature, and wind speeds into our data. Otherwise, we are afraid that if high wind speeds, and rainfall did not occur on the day measurements were taken, their effects would be overseen. To get these weather readings we used Miami's home web page.
We will be using disposable cameras to take pictures of the peeling, a tape measure to measure to amount of bark that has peeled for each observation, a chair so measurements can be taken on higher parts of the tree, a calculator to find the mean, median, mode, and standard deviation of the peeling rates, and film that will be processed so the physical changes can be seen.
We plan to involve the class by dividing them into three groups where each group will be taken to the different tree. There they will make our observations for the day including measurements, pictures, and the recording of the data. They will also be factoring in the weather for the day such as the temperature, and then the weather patterns for the week by using Miami's home web page. In order to make these measurements and recordings; each of us will be at the trees helping them with what they need to do. In addition, they will each be given a handout/data sheet with all requirements included. This is so we can monitor the measurements each group came up with, and to make sure no group left out any observation or important piece of information. This data sheet will include the measurements for all the four spots on each tree asking for the total length of the bark, and then the total length of the peeled bark. We hope that through these hands on experiences the class will become more interested in why the tree peels, what makes it peel, and why they should learn more about our research plan. We also feel that having the class take an active part in our lab will allow them to feel apart of our presentation, since they helped collect our data. This is important because without data we would only have background information, which gives us nothing pertaining to the peeling process. Experience is the key to knowledge.

4. RESULTS:
Throughout the course of our study on the American Sycamore tree, which lasted roughly twelve weeks we continued to measure the amount of peeled bark off the six trees studied. Although we originally thought the combination of the location of the trees and the weather would affect the rate at which the trees peeled, we were proven wrong through our data and figures. Our null hypothesis is that there is no difference between location, humidity, temperature, or wind speed as it relates to the rate at which these trees peel. Thus, through our results and conclusion we will prove that our study was unable to disprove the null hypothesis.
At figure 1-A the total length of bark peeled for all six trees is given. As noted, tree "e" which is located on the corner of Patterson and Chestnut had the highest levels of bark peeled. Tree "a" on the other hand peeled the least leaving the question why one would peel significantly more than another did? In answer to that we can say that the temperature is ruled out as a possible explanation for this difference. Although we didn't take the size into consideration the rate of peeling seemed to be individualistic for each tree. On data sheet 1-B the interactive bar graph shows that even though there is a difference between the amount peeled in hot temperatures versus cold temperatures, in order for this variable to affect the outcome there would not have been such high levels of peeling in moderate temperatures. We would have thought that peeling would have occurred at one extreme or the other. This conclusion can also be seen on figure 1-C, which shows that the p-value of the amount peeled versus the temperature is .5032, meaning something other than temperature is controlling this rate.
Next, are the comparison among wind speed and the amount of bark peeled. With a p-value of .2505 we again can't disprove the null hypothesis. As noted on figure 1-D a slight shift can be seen as the wind speed increases, but the increase is so minimal that the data is hardly conclusive. Although it appears there were more windy days during our study than not, the regression plot graph shows that the standard deviation varied relatively similar on windy days and calmer days. In correlation to this, figure 1-E supports that even humidity and wind together didn't affect the peeling very much.
Since we have already ruled out the possibility of the temperature, wind, and humidity affecting the rate at which our studied American Sycamore trees peeled we are left with two more variables that might help conclude our study. These include the location of the trees and the location of the peeling on the tree, for instance whether the peeling was done on the trunk, or on a limb. In Figure 1-G our data actually goes against our original thinking because the trunks peeled more than the limbs. This interactive bar graph proves that there is not much difference among the peeling on the trunks versus the limbs. I guess now that we have factored in that weather doesn't play a part this conclusion doesn't come as such a shock, but since we thought weather did play a part we figured that the trunk would peel lees than the limbs because it was better protected from the elements. In addition, figure 1-H tells us that the amount of peeling per tree varied only slightly, which means again we must accept the null hypothesis. Even though the Bar chart makes it look like there is a large difference between tree "A" and Tree "e", when we look at the amount peeled in numbers we can see that there really isn't much variation.

5. DUSCUSSION AND CONCLUSIONS:
By interpreting our results we have ultimately found that we could not reject the null hypothesis which is that there is not significant difference between the amount of bark peeled in relation to weather and location. All of our p-values for all of the tests done on the stat-view find were significantly higher than .05 meaning that there is something else affecting the peeling. Because of this we have come to the conclusion that since the American Sycamore tree peels in order to grow that the reason weather and outside influence doesn't hinder or activate anything is because the peeling must be completely dependant on the age of the tree and the amount of growth occurring. Although outside influences could cause the bark to fall off the tree, it is not able to make the tree begin the peeling process. This in tern is connected to why we think the trunk actually peeled slightly more than the limbs. After running the tests we began to think of the possibility that more growth occurs at the trunk than on the limbs, thus it is a quicker process.
Additional questions beyond the research we have completed include testing other variables in relation to the trees peeling. This would include the dew point, many more trees, trees of different sizes in relation to those of the same size, and a much longer observation period. Since this lab took place between September and November we were not able to get drastic differences in our temperature readings. By the time we had begun the study, the weather had significantly cooled down in comparison to summer heat, and on the flip side, our study ended just before the real winter bitterness entered the weather scheme. Although most of our testing concluded that most of the peeling happened in moderate temperatures, we think part of that has to do with the fact that we never experienced extremely different weather patterns. Even though we were unsuccessful in uncovering the material we had hoped to discover, we were still able to learn how to successfully run our own scientific study. Given more time we could have seen significantly different results. In addition, none of our trees were located directly near a water source, which could have also altered our results since the American Sycamore tree thrives in damp, moist areas.

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