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| Site 5 is composed almost entirely of jack pine. All the jack pine appear to be the same height, which could indicate that this is an even-aged stand of trees. Jack pine have lots of bare branches all along their trunks, so although the understory looks dense in the bottom photo, this could be partially due to all the bare branches and the fact that the trees are closely spaced. | |
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Jack pine are evidence of a disturbance, and the disturbance they are most closely associated with is fire. The cones require fire to open and release the seeds. Thus, this stand of trees is a result of fire. Jack pine are an example of a "pioneer species," one of the first species to move in after a disturbance. A fire occurred in this area in 1966, so this stand is approximately 32 years old. Although there are plants growing in the understory, there are no jack pine in the understory; young jack pine cannot tolerate shade. These trees require high sunlight. After growing to their present height, these trees have created a shady environment that the young cannot survive. Over the next several hundred years, these jack pine will slowly be replaced by other trees such as red or white pine, birch, maples and oaks. For a summer view, click here. |
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| Although stop number 5 is our last site for taking notes, lets just go a little farther and check out the lake. The lake, like many of the other ecosystems in Schmeeckle Reserve is human-made. It was dug out between 1975-77. Jack pine were planted along the shore for soil stabilization, so the vegetation surrounding the lake is also not natural. | |
| The lake contains aquatic ecosystems quite different from those we've observed on land. Keep in mind that approximately 70% of the earth's surface is covered by water, and as we begin to explore global patterns to ecosystems in class, we will only examine terrestrial ecosystems; we will not examine any aquatic ecosystems. |  |
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After completing this field trip, you should have an appreciation of the variety of ecosystems located within the small space of Schmeeckle Reserve. Even if we can't identify all the species within each community, we can still observe some of the similarities and differences between these communities. |
| We should be able to attribute some of these differences to variations in environmental situation (sunlight, water, etc...), and thus, we should be able to explain some of the geographic patterns to ecosystems within the reserve. This ability to explain geographic patterns will help us as we start looking at global patterns to ecosystems in lecture. | |
The day we actually did this trip, the air temperature was approximately 8F when the first lab section walked the trail (8:30AM). By the time the the third lab section walked the trail, the temperature had risen to the middle to high twenties (1:00PM). Some of the pictures were taken in the morning, but most were taken around 2:30 PM.
Created by Karen A. Lemke (klemke@uwsp.edu). Last modified July 13, 2000.