In order to do this, we consulted the Society of American Forester’s Forest Cover Types of the United States and Canada. In essence, a cover type is a specific stand type. For example, the Sugar Maple cover type is comprised of a majority stocking of sugar maple. Although ultimately determined by the significance of the one tree (or multiple tree species for some cove rtypes), each cover type has certain expected constituents that help to form the stand.
We determined the different cover types throughout our stand, and conducted vegetative surveys based on fixed radius plots. By creating seven representative 5-meter radius plots, we were able to survey a small area so as to project the findings to a larger scale.
These plots were scattered throughout the three stands that we delineated. All had high abundances of wood fern, ostrich fern, and raspberry. There is a northern Sugar Maple-Basswood stand (NSMB), a southern constituent of the same cover type (SSMB), and an Eastern White Pine (EWP) stand occupying the center of our 1-hectare study area. Two of the sample plots were in the NSMB stand, four were in the EWP stand, and one in the SSMB stand. Each plot was placed so as be representative of both the stand itself and the hectare as a whole (i.e. more plots in the EWP stand because it is the largest stand).
Sugar Maple-Basswood Stand
(Photo courtesy of Kevin Osantowski)
We sampled all trees greater than 6 inches in diameter within each plot and recorded the tree species, diameter at breast height (dbh) in inches, and merchantable tree height (bole length from base to where it tapers to 6 inches) in feet.
Some of the calculations we determined with these findings are as follows:
-Basal Area per Hectare = 396.5 ft2
-Board Feet per Hectare = 11374
-Stems per Hectare = 454.7
Of particular interest is the particular composition and structure based on the stand type. The following table shows plot locations as well as the tree species and sizes found within:
| Plot Number | Location | Tree Species (dbh, merchantable height) |
| 1 | SSMB | Basswood (16, 45), northern red oak (14, 54), basswood (16.5, 59.5), sugar maple (17, 55.5) |
| 2 | EWP | Green ash (7, 28), eastern white pine (14, 52) |
| 3 | EWP | Eastern white pine (8.5, 72), eastern white pine (17.5, 75.5), eastern white pine (17, 66.5) |
| 4 | NSMB | Basswood (15, 52), basswood (13, 49), sugar maple (13, 45), ironwood (6, 20) |
| 5 | NSMB | Bitternut hickory (10, 50.5), sugar maple (6, 20), sugar maple (10, 56.5), sugar maple (13, 57.5), sugar maple (7, 45) |
| 6 | EWP | Eastern white pine (12, 55), northern white cedar (6, 20), northern white cedar (6, 20) |
| 7 | EWP | Eastern white pine (17, 85), eastern white pine (21, 65), American elm (6, 20) |
These findings can be taken to determine tree density, or stems per hectare. The following graph shows the distribution of various trees within the plot:
When only considering timber volume, the primary constituent of both of the SMB stands was basswood. However, based on number of stems, sugar maple was more common. In reality, both are likely equally important in these stands. As would be expected, the primary constituent of the EWP stand was eastern white pine. Timber volume, or board feet, is estimated based on dbh and bole height. These findings can be seen in the following graph:
The aforementioned material can all be complied to determine stocking of the stands based on species. Also, it can lend insight to the status, or successional age, of the study area.
Another way of looking at the ecosystem is less of an "in the present" approach, but rather a way of characterizing the landscape based on its probable mature community. This is called a natural community. Think of it as a description of the site based on its abiotic features like the soil as well as aspects like the topography. These pool together to make certain features that are best for certain forest types. However, forests are ever changing, so a snap shot, like cover typing, is only part of the picture. Natural communities are what will likely be present if a stand is left to its own natural accord for years.
In our case, we see the plot as all being a Rich-Northern Hardwoods community. It is characterized by sugar maple and rich sites species like basswood and bitternut hickory. The soils are intermediate in moisture, and generally have nutrient rich parent material, like the limestone that we see here. The vernal pool found in the center of our plot offers much of the moisture to the site, as it then drains through the southern part of the stand.
This Rich-Northern Hardwood community is likely what the woods looked like 400 years ago, prior to human intervention and agriculture. Disturbance was not a factor at that point. The forest had been left to its own accord until human intervention. However, at this point in time, we are seeing a successional stage in between what the woods once were and what they will very likely become.
Considering the presence of the Sugar Maple-Basswood cover type, it makes sense to call the stands Rich-Northern Hardwood, but what about the Eastern White Pine stand? In this case, we must think of a tree's place in succession. Eastern white pine is often not thought to be a climax species. It is instead characteristic of mid-successional disturbed areas, where it will one day yield to more hardy hardwoods that will characterize the climax community. The lack of eastern white pine regeneration supports the idea that this forest will be far different in composition in the years to come. For now, we're left to ponder the disturbance, potentially agricultural or natural, that led to the establishment of this eastern white pine cohort.
One intriguing part about these types of sites is the productivity. The site was abound with healthy, fast growing trees. Of particular interest was the largest tree that we found on the site. In the northeast corner of the study area, there is a large white ash. Its dbh is 27 inches, with a bole height of 70 feet. At around 7 feet up, the bole splits into two main stems, both very sizable on their own. The nutrient rich soils provide the medium for trees to grow quickly without succumbing to other environmental stressors as easily.
Much of the surrounding forest seems to show these same trends. However, once you travel up in elevation, you begin to see much more dry site constituents. Overall, the parent material and surficial geology of Niquette Bay allow for very rich soils, and thus, rich site competitors. It then becomes a question of soil moisture content to determine the cover type, or ultimately, natural community.
The soils are a basic feature that play heavily into the vegetative communities that will be present. The rungs of the ladder go one further, as much of the vegetative composition plays heavily into habitat suitability and quality for various animals.
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