Introduction

In conjunction with the University of Vermont, we conducted an ecosystem survey of various plots within Niquette Bay State Park. We are only 1 of 14 groups that studied a hectare within the park. Our analysis included land history information, soil and geology data and sampling, vegetative composition and structure, as well as habitat suitability. The goal: to compile this multidimensional study in a manner so as to be able to assess the ecosystem conditions of the site. This will provide information that can help in monitoring the impacts of present use, as well as help to understand what is really going on in the park. For anyone curious, we will be able to map and describe much of the environment within the park. This will include, at the base, soil and vegetative descriptions, which can be extrapolated so as to provide wildlife and natural community information. All of this data will be most useful when compiled, and researched, using all of the study plots together.

Our plot, Plot 10, just like the rest of the park, has not always been a place for the public to peruse and explore. Instead, certain clues led us to see a much different story. Barbed wire and old stone cobble fences littered the site. There was even an old sink hole from where a well once was. What we can assume, partially from this and partially from historical data, is that the area of the park was agricultural at one point. Rather than being state land for public use, the woods here were instead private, and were more than likely not wooded, but instead pasture land.

Plot 10 is mainly a rich northern hardwood stand. There were two cover types, or tree composition classifications, present; being Sugar Maple-Basswood and Eastern White Pine. However, the Eastern White Pine stand showed little regeneration, so we have reason to believe that the entire site will be a rich northern hardwood stand once it reaches a late successional stage. As of now, the most common trees are eastern white pine, sugar maple, and basswood. One of the most unique aspects of our site was a vernal pool. Small pockets in the earth held inches of water, and the rest of the ground in the area was heavily saturated mosses, that gave way easily to expose standing water. This area holds some of the greatest diversity, not only within our site, but likely the park as well. Many amphibians and wet site plant competitors could be found here. Many of these also likely rely on the year round presence of this saturated site.

These woods, although part of a well used trail system, offer some of the best habitat in the Burlington area. As much of the surrounding land is fragmented for development, agriculture, and other private uses, Niquette Bay offers a comparatively vast tract of land to serve the ecosystem. Any species from the red-backed salamander, to white-tailed deer, to wild turkey are offered refuge. With the completion of this study, we hope to describe what an important asset Niquette Bay State Park is for the surrounding area.

The following map shows the corner markers to Plot 10, and allows for a visual exploration of the surrounding area:


View NBSP in a larger map

Land Use History

One factor which may have influenced the nature of our site's substrate was made evident by the presence of low stone walls, old fence posts, barbed wire, and the remains of an old well. The well and fence posts were both located towards the north western end of our plot. The stone walls ran from north to south along our hectares eastern side and the barbed wire ran from north to south along the western side. The presence of these objects within our hectare suggests that at one point our site had been used for agricultural purposes. It remains unclear how long ago this might have been however, judging by the size of some of the trees on our site it must have been a very long time ago. Some of the larger eastern white pine, sugar maple and ash trees must be in the range of 100 years old. So if our site was used for agriculture at some point in the past it must have been no sooner than the early 1900s.

Soil Characteristics

The major driving force behind the formation and toposequence of the soils at our site can be traced to the Champlain Sea. During the end of the last Ice Age as the glaciers retreated huge volumes of water were released.  (Klyza, Trombulak)  The drastic effect this had on the landscape is still evident and can be seen through an examination of our hectare’s soil structure and surficial geology. Overall, the surficial geology of our hectare mainly consisted of very fine sand, Champlain sea clay, and nutrient rich parent material. Aboveground this is reflected by our site’s vegetative composition and the presence of rich site competitors such as basswood and bitternut hickory.

Within our hectare the 3 main soil types were determined to be Farmington Extremely Rocky Loam (FaC), Munson and Belgrade Silt loams (MuD), and Hermon Extremely Stony Fine Sandy Loam(HnE). Farmington Extremely Rocky Loam soils are typically found on slopes of 20% to 60% grades. This soil was found towards the western side of our hectare where the grade was steepest. The second soil type, Munson and Belgrade Silt Loams, are typically found on slopes of 12% to 25% grades. This soil ran through the center of our hectare where the grade slightly leveled out. The third soil type, Hermon Extremely Stony Fine Sandy Loam, ran along the eastern side of our hectare and is usually found in regions where the grade is between 15% and 60%. When we applied hydrochloric acid to one of the rocky outcrops on our site it slowly bubbled and so we determined it to be Dunham Dolostone. The rocky outcrop was a light gray-brown color with a very coarse composition.

Using an auger the soil pit we dug exposed the following horizons: The O horizon was only about 1 cm thick and consisted of decomposing organic matter, mainly leaf litter. The next horizon, the A horizon consisted of dark brown mineral soil with mixed organic matter. It also had a pH of 7.0, a loamy/sand texture, and was measured to be 15cm thick. The B horizon was comprised of a reddish-brown soil with a pH of 7.0 and was measured to be 23cm thick. Its texture was determined to be a sandy/loam. The C horizon mainly consisted of gray-brown clay, very fine particles, and had a pH of 7.0.                                                   

Works Cited
Klyza, Christopher McGrory., and Stephen C. Trombulak. The Story of Vermont: a Natural and Cultural History. Hanover, NH: University of New England, 1999. Print.

Vegetative Composition

Part of the study at Niquette Bay State Park was designed to determine the vegetative composition of the site. In order to do this, we had to delineate the different stands within our study area. A stand can be thought of as a forest patch with similar composition, structure, and ultimately, ecology throughout.

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.