Analyze Your Town’s Ecological Landscape

Black bear
Black bear
Ecology is the study of organisms, their environments, and the interrelationships between the two. While the focus of a cultural landscape analysis is on the relationship between humans and the land over time, your ecological landscape analysis will emphasize the non-human organisms with whom we share the local landscape. This distinction is not meant to promote humans as being separate from nature, but rather to draw attention to ways in which we influence (and are influenced by) the non-human components of our landscape. This concept is explored in greater detail in the Integrative Analysis section of this website.

The PLACE Program utilizes a “pieces, patterns, and processes” approach to ecological landscape analysis. The pieces can be thought of as the different plant and animal species that inhabit the town, while the patterns are the manner in which they are distributed across the landscape. Processes refer to the forces (such as

Aerial view of Richmond
Aerial view of Richmond
disturbance, climate, and soil chemistry) that drive these patterns. For example, when analyzing a town from an ornithological perspective, we might ask questions such as: What species of birds species nest in the town, and where? Which birds are common and which are rare? How have their populations changed through time, and why?

To truly understand the pieces, patterns and processes that shape your landscape, you will need to study how the plants and animals of your community respond to their environment though time. Historic maps and census data, combined with current information and field observations will be your best tools for getting to know your ecological landscape. We know that human impact has changed Vermont’s ecological landscape enormously over the last 400 years. Some changes are obvious, such as the extinction of certain plant and animal species, but other changes more subtle, like when wildlife (i.e., coyote and fisher) adapt to new habitat opportunities. So as you begin your ecological investigation, be sure to look for patterns in how species have been influenced by changes in the physical and cultural landscape.

On this website we have chosen to break up the ecological landscape into three broad categories based on scale, and a common set of patterns and processes. Plant communities develop and respond to certain elements of the physical environment such as soil structure and chemistry, topography and climate. Wildlife habitat is in part governed by these factors, but is also impacted by vegetative structure and human disturbance on a larger scale. Aquatic communities respond to soil and bedrock chemistry and climate, but are also very much shaped by the properties of water.

» Plant Communities

A plant community is an assemblage of plant species found within a specific area. The physical boundary between one community and the next is not always clear, but ecologists try to look for natural groupings. For example, a meadow is a plant community consisting of grasses and other flowering plants. A relatively dry meadow in Vermont would be home to species such as daisies, milkweed, goldenrod and fescue. The exact combination of plants you find in any plant community such as a meadow will depend on which species were able to colonize the area and their interaction with the rest of the community.

forest
Upland deciduous forest community

Landscape analysts are interested in the distribution of plant communities for many reasons. Classifying and mapping plant communities tells us how plants are responding to their physical and biological environment, allows us to estimate the biodiversity of an area, and guides land-use planning, forestry and natural resource management. There are several methods used to map plant communities. Some are based on intensive inventories and fieldwork, while others interpolate data based on aerial infrared photography. Some methods provide finer scale mapping than others. Large-scale “land use” maps usually break the landscape into 7 - 15 general categories that include some plant community categories such as crop fields, hard wood forest, and deciduous forest and may help you gain an overview of land use patterns and plant communities in your area.

The dynamics within plant communities are fascinating. However, the spatial distribution and species interactions within a plant community are usually strongly affected by the surrounding environment. Plants respond to soil structure and chemistry, hydrology, and climate. Plants create their own environment as well. Roots change the soil structure and chemistry, and contribute to the weathering process that creates more soil over time. Leaves and large branches create shade and retain moisture in an area and thus create cooler, damper and darker micro-climate that may or may not be favorable for the growth of other species.

Competition between plants and between plants and animals (mainly insects in Vermont) is a major factor that shapes how and where plants are able to thrive. Some plants, such as cinnamon fern have restricted growing conditions and grow under very specific environmental conditions, while others, such as red maple, can tolerate and compete under a wide range of conditions. Some plants compete so successfully

spleenwort
Spleenwort and lichens
that they are known as invasive species. Many of these species are not native to the area but were brought here over the last four hundred years. Most came in the form of seeds attached to livestock, mixed into hay or carried in manure. Some, such as common yard grass species are so well established that the original plant community no longer exists. But others like bittersweet, honeysuckle and purple loosestrife continue to expand their territories and threaten to out compete native forest and field plant species. There are several statewide programs that aim to control the growth of exotic invasive plant species.

As you learn about the plant communities in your area, you will begin to see patterns. Try to identify all of the factors of the physical landscape that shape the patterns you observe. As you learn each new plant in your community, look for signs of how it might interact with other plants or animals. Look for patterns in the distribution of native and non-native species; this might help you further identify the relationship between the cultural history and natural history of your area. Finally, learn to identify the invasive plant species in your area and note their distribution over time.

Shelburne’s Plant Communities

The rich diversity of plant species and communities currently found on the Shelburne landscape is a reflection of many factors, most notably the relatively long growing season, the diversity of soil types, the history of intensive agriculture, and the calcium-rich bedrock. The forests that make up about one-third of the landscape are relatively young, generally having only been released from agriculture within the last century.

forest
White Trillium in bloom near Shelburne Pond

The upland forests in town tend to be composed of tree species that take advantage of the relatively warm climate (i.e., oaks and hickories), along with those that that compete well when the soils are rich in nutrients (i.e., basswood, ash, butternut, and sugar maple). Floodplain forests dominated by silver maple and green ash are well-represented along the mouth of the LaPlatte River, while the examples of the once extensive clayplain forest are quite rare, with Church Woods at Shelburne Farms being perhaps the only viable remnant.

Springtime in the upland forests of Shelburne is a beautiful and much-anticipated event, when carpets of trillium, wild leeks, bloodroot, along with other spring ephemerals are found blooming in great numbers before the deciduous trees leaf out. The upland forests around Shelburne Pond are particularly renowned in this respect.

Resources

» Wildlife Habitat

Vermont’s wildlife populations have fluctuated through time, but they are still a notable presence in our communities. Today Vermont is home to 62 species of mammals, 237 species of birds, over 80 species of fish and countless invertebrates. It is common to assume that wildlife habitat is restricted to the forest or other wild place, and while

snow geese
Snow geese in Addison County

it is true that most animals have adapted to specific natural environments, this does not mean that there is not good potential wildlife habitat all around us. In fact many animals, large and small, live and move seamlessly through our villages, towns and cities. An over grown back yard can be home to dozens of voles, and your porch eve may be a phoebe’s favorite nesting spot. As we learn to identify the resources that are important to wildlife, we see more clearly the relationship between the cultural and natural environment.

As you explore your landscape, think like an animal. How are food, shelter and water connected in your habitat? How do cultural features break up or enhance the habitat? It’s important to think of your landscape at the appropriate scales as well. For example, by the time a

phoebe
Phoebe
juvenile tree swallow reaches the end of its first summer it has explored all of the power line perches, shallow pools of water and wheat fields in its territory. It glides effortlessly over highways and rivers, and by early fall it is ready to leave its parent’s home territory and head south for the winter. A red-backed vole born in the same pasture as the swallow is not so lucky. As it grows to maturity and wanders further away from its natal territory, it will encounter many of the same landscape features as the swallow, but with more dire consequences. At worst it will not survive the dangerous four-lane highway, irrigation ditch, and mowed power line, at best it will be forced to share limited habitat and resources with its parents and siblings.

We could study the effects of development and fragmentation on every single organism on our community, but most wildlife biologists work with just a few focal species within an area. There are a few ways that information about just one species can tell you about many of the other animals in your community. Top predators such as wolf and bobcat are known as keystone species because they control the entire food chain

moose
Moose
below them, from deer and rabbits, to trees and herbs. Other species such as bear or wolverine require large areas of high quality habitat. A decline in these populations often signals the early effects of fragmentation, while an increase could indicate a broad scale regeneration of habitat.

As you learn about the wildlife species in your community, remember that with few exceptions, their welfare is intimately connected to your town’s development and conservation strategies. Find out how certain populations have changed over time, and see if you can discover what they are responding to. Some animals such as white tailed deer do very well in agricultural areas where there is abundant edge habitat and palatable vegetation. Others such as river otters, will only survive in a forested riparian habitat. Land use strategies dramatically impact animal populations, but look for other forms of human impact as well such as pollution or over (and under) harvesting of game species.

Shelburne’s Wildlife Habitat

The diversity plant communities and landforms, along with an abundance of water, make the landscape of Shelburne suitable habitat for a diversity of wildlife species. An experienced team of birders, for example, can expect to detect over 100 bird species during the peak of migration in late May. The upland forests provide breeding habitat for a colorful suite of wood warblers migrating north from Central and South America, while the wetlands around Shelburne Pond and the mouth of the

Shelburne Pond
Shelburne Pond
LaPlatte River attract a range of waterfowl and marsh birds, including the elusive Virginia rail and American bittern.

The areas in close proximity to Shelburne Pond also tend to provide excellent habitat for reptiles and amphibians that are otherwise rare in the state, such as the northern water snake and four-toed salamander. The LaPlatte River also functions an important travel corridor for many species, including black bear and moose - both of which have been encountered there in the recent past.

While fragmenting the habitat of certain wildlife species, the extensive grasslands and forest edges associated with the cultural landscape of the town actually improve the habitat suitability for species such as bobolink, savannah sparrow, indigo bunting, and white-tailed deer.

» Aquatic Communities

Today, all of the aquatic communities in Vermont are fresh water. These include rivers, streams, lakes and ponds. Bogs, fens, marshes and swamps are wetland communities that are shaped by both aquatic and terrestrial processes.

beaver swimming
Beavers: the architects of aquatic and wetland communities
One or more of the following processes will affect all aquatic and wetland communities to some degree: nutrient availability, water currents, freeze-thaw cycles, average water depth, water table fluctuations and flooding. Depending on how each of these processes shapes the community, different plants and animals will thrive in different aquatic environments. For example, emergent plants grow in calm, shallow water where there is adequate access to sunlight and protection from strong uprooting currents.

Many of Vermont’s water bodies are remnant features of the last glaciation. Lakes and ponds were left behind in depressions carved out by the glacier and some were formed by melted ice water. River valleys are widened or shaped first by glacial ice and later by glacial melt water.

One important aspect of all water bodies in Vermont is that they are continually changing their shape and depth. Sedimentation and shifting hydrologic patterns result in lakes shrinking, rivers shifting, and marshes drying up. Because aquatic communities are so dynamic, they require large, specially protected areas to

turtle swimming
Painted turtle
thrive over long periods of time. Many nutrients and pollutants are soluble in water, and are easily transported throughout the community. Aquatic communities are especially sensitive to changes in pH, and contamination by limiting plant nutrients such as nitrogen. The result is that the many plant and animal species that depend on Vermont’s aquatic and wetland communities for part or all of their lives are continually threatened by the loss and contamination and aquatic habitats. For example, the Restrictive Arm (the northeastern portion) of Lake Champlain regularly receives large quantities of agricultural run off. The fertilizers and pesticides that work to make Vermont’s farms productive on land, act as deadly pollutants in the water. The result is an overgrowth of algae and bacteria, and the death of many aquatic plants and animals. In general, aquatic communities are more sensitive to, and take longer to recover from pollution than do terrestrial environments.

A good way to explore the aquatic communities in your area is to first look for surface water features on a topographic map. If you have a body of water near by, look for vegetation around the edges and

floodplain
Riverine-floodplain community

in the water. Technically, a pond is shallow enough to support plant growth, and a lake is too deep to support plant growth (generally over six or seven feet deep). Check the banks for muskrat holes, and muddy shores for the footprints of any other wildlife. Look at the larger landscape context of the area. Are there large fields, forests, roads, farms, or developments near by? Is the water body man-made (as in surface water treatment ponds) or can you a distinct inlet and outlet. Be sure to look at a watershed map of your area to see where your body of water fits in. If you live on a major river it will be helpful to know about any dams or sources of pollution up stream. And finally, there are dozens of non-profit groups in Vermont that are based solely on the protection of specific water bodies or watersheds. These groups will be a great source of information to you as you put together the story of your landscape, and contemplate the protection of your community’s aquatic resources.

Resources