Figure 1: Location of Tree “X”
1. The tree that I’ve chosen to observe from March to June is located between the playground and the Main Hall, to the right side of the building. From the exterior the tree shows characteristics belonging to coniferophyta, as its needle-like leaves distinctly imply. For ease of addressing the tree, I have named the tree as “X.” The following series of observations will mainly focus on:Determining exact taxonomical nomenclature of “X”
2. Observing the color of leaves weekly
3. Observing the bark of “X”
4. Observing reproductive actions (if any) of “X”
5. Determining human / environment influence on “X”
These objectives will be the center of my observations which will take place on a weekly basis. During the course of my observations, I will try to find out the exact species of “X” and this will provide guidelines for further observation points. My initial observation is Mar. 27, 2012.
Classifying Tree “X”
“X” most likely belongs to Kingdom Plantae and Phylum Coniferophyta, by its most basic traits. It is immobile, has a hard stem from which branches develop, have roots, and have needle-like leaves that are generally green in color. From research, I have found a web article illustrating on method of classifying pines, which belong to Class Pinus. I am not yet certain whether or not “X” belongs to Class Pinus, but this article may serve as blueprints for formulating my own dichotomous key.
My initial observations on Mar. 27th provided me with basic knowledge about Tree “X.” “X” has needle-like leaves whose color ranges from olive yellow to dark green. Yellowish leaves tend to be more located to the bottom of the tree whereas the top has mostly dark green leaves. The branches seem to be clustered—meaning that multiple branches project from the stem in same height location. This may be of help in classifying “X.” So far, no signs of reproductive action are visible.
Figure 2: Sketch of Tree “X”
Figure 3: Photograph of Tree “X” taken Mar. 27
I was able to implement biweekly observations since April 5, with the five pre-set objectives as the main focus of my observations. A common noticeable point during the observations was that there was little change in the outlook of the tree “X,” despite the abrupt changes in leaves and flowers of nearby plants and trees. This may be explained by the fact that “X” is coniferous, since conifers maintain green leaves throughout the year. However, some minor changes in “X” were also visible.
I attempted to photograph “X” from the angle and distance that was closest as possible to the original photograph taken in March (Figure 3). As the photograph on the left (Figure 4) shows, the tree does not display abrupt changes in its general appearance. However, some changes in color are visible, as the color of the leaves on the bottom left appear to have become greener than its original yellowish-olive color. Also, the overall leaves were greener than observed in March. Other than that, not much change is visible in “X’s” general appearance.
In the April observations, more in-depth examinations of tree “X” with particular interest to the shape and the structure of leaves were conducted. The reason for this is the fact that trees under Class Pinus are often distinguished from each other by the shape and the structure of leaves.
Figure 4: Photograph of “X” taken Apr. 26
With further research, I’ve also found and listed other factors that can be used to distinguish species within Class Pinus: leaf length, leaf pattern (how leaves are connected to the stems or branches), shape of the bark, appearance of tree bud, etc. Of these, I was able to identify some noticeable characteristic in the pattern the leaves projected from the stems. First of all, the individual needles were protruding in outward direction, slightly slanted towards the end point of the stem. While the leaves were not in pairs or groups of three, they were gathered altogether within a small distance; one sample branch had 18 leaves closely located. Figure 5 shows the pattern of the leaves attached to a branch. This can be a factor of distinction of “X” that rule out possibilities of species with paired needles.Figure 5: Leaves’ Pattern
Another discovery during April observations was the indication of “X’s” preparation for summer. At the end of each branch, there was a budding projection, which could either be a cluster of newly produced leaves or a new branch. Further research and observation is required in order to figure out what this is.The bark of “X” was also observed. The dark brown, rough surface of the bark showed no visible sign of change; this is normal assuming that trees do not grow out of their barks in a short period of time.
Figure 6: Budding from Tree “X”
Season Shift and Relevant Changes
Figure 7: Temperature Comparison: May 5th vs. June 2nd
Seasonal temperature and daylight change occurred during the course of my third observation period. According to Korea Meteorological Administration, the average temperature of the area (Suwon, which is the nearest local measurement) on May 5th was 17.8 degrees Celsius, whereas the highest and the lowest temperature for the day were 24.9 and 12.7 degrees Celsius respectively. For June 2nd, the average temperature was 22.1 degrees Celsius and the highest and lowest were 28.5 and 17.5 degrees Celsius. Processing this data into a form of a graph (see Figure 7), it could be drawn that the highest, lowest, and the average daily temperature all increased, with the average increase being 4.3 degrees Celsius. Another notable change was the daylight hours. I had expected that the daylight hours would increase from May to June, as it is a common knowledge that summer has the longest daytime hours. However, according to the KMA measurement, the amount of daylight received was actually lower in June 2nd (7.5 hours) compared to May 5th (12.2 hours). Possible cause for this is the increase in precipitation due to increased occasion of rainfalls during the course of the third observation. Along with temperature, these data would serve to help determine causes for changes in Tree “X.”
The size of Tree “X” did not show any significant changes, whereas the color of the leaves showed significant change. Compared with the photographs of Tree “X” on my last observation, the color of the leaves became greener, now with slight brownish shade (the conventional dark green pine color), although not dark enough to be a completely different color. The yellowish color on the leaves located at the lower part of the tree was now not visible, but the overall addition of brown was now in place. The limitation of this is the fact that colors of photographed images are highly dependent on the camera used, light conditions, humidity, et cetera. However, there is a chance that the increase in precipitation caused this (at an observation of this level proving this statement is not possible, but research showed that the shade of the needles have some to do with its access to water. On the other hand, it was now observable that the buddings discovered in the previous observation had turned into a newly sprout cluster of needles, a young new branch. Several of these were visible around Tree “X.” Also, there were some brown buddings along with some brown leaves at the end that seemed to have died out. Connection to weather, however, cannot be determined.
Quantitative Observation & Evaluation
Since there were no previous quantitative data collected from two prior observations, it was not possible to show a quantitative data comparison of Tree “X” in accordance to time progression. Thus, I decided to inquire about the length of Tree “X’s” branches from different levels of height. A long strip of string was used to measure the length of six branches of Tree “X,” from six different levels of height. One end of the string was pinned to the stem part of the tree and was stretched towards the farthest end of the branch to measure the length of each branch. Length did not include the length of pine needles at the end of the branches.
Table 1: Length of Branches according to Height
The data showed that the length of branches increased at lower height and started decreasing as heights of the branches increased. A question as to what is the reason for trees’ behavior to develop shorter branches at higher positions rose up; through research, two probable answers were achieved: the lower branches were the earlier ones, with more time for growth; the shape maximizes surface for receiving sunlight.
A graph could be drawn from the given data, with the length of branch on the x-axis and the height of the branch on the y-axis. I expected the shape of the graph to resemble the silhouette of Tree “X,” in a simplified form. The graph on the following page is the result of the plotting:
Figure 8: Silhouette of Tree “X”?
Ending the Observation of Tree “X”
The final conclusion to the three-month observation yet leaves many initial questions unanswered. Not enough research on discovering the exact nomenclature of “X” was conducted. As a result, I could not find out the exact taxonomical name of Tree “X.” However, many other traits such as the change in the color of needles (despite the term “evergreen”) and the mechanism for budding of new branches could be observed and recorded. More questions that could be answered with a more prolonged observation would be: changes in number of leaves during the course of the year, changes in color, changes in the thickness of the stem (growth speed), et cetera.