Mad River Valley Natural Heritage Inventories
In 2007 and 2008, Arrowwood Environmental was hired by the towns of Fayston, Waitsfield, and Warren to create inventories of the Natural Communities of the three valley towns. The work was made possible by a Vermont Agency of Commerce and Community Development Grant. Project goals included identifying, inventorying, assessing, and ranking the following types of natural resource elements:
- Wildlife Habitat
- Upland Natural Communities
- Vernal Pools
- Connecting Lands and Rare Elements
The first step involved remote landscape analysis. This was followed by a public input process as well as field work. Finally, maps were generated to highlight key resource areas.
In the same way that we depend on farms and gardens to provide us with plentiful food, animals also depend on adequate food sources and access to them. Often, these food supplies are found in forests and other natural areas that connect across a broad area. CHUs represent a combination of wildlife habitat types, critical for the maintenance of animal populations.
The deepest, largest, and most protected part of the forest is termed the "core" area. Wetlands, upland natural communities, vernal pools, and areas containing rare plants may be a part of these core areas. They may also exist along the edges and serve as linkage areas that allow animals to move freely from one feeding area to another.
It is in the core forest that most wild animals are able to reproduce and contribute to the restocking of their populations. The larger an area of undisturbed core forest, the more likely it is to remain stable over a long period of time and to provide adequate habitat. Additionally, the greater the vegetative diversity in the CHU (including the core area), the greater the diversity of animal species the area will support (assuming the area is appropriately filled with native species that support native wildlife.) Animals of varying types require different materials for shelter and food, so it makes sense that a diversity of habitat types increases the range of animals. In temperate forests, CHUs are generally comprised of some combination of the following habitat types and/or features:
- Ledge, Talus, and Cliff Habitat
- Bear Wetlands
- Early Successional Habitat (ESH) (young forests with shrub and/or saplings present)
- Forested Riparian Habitat (streamside forests)
- Mast Stands (offer trees such as oak and beech that are valuable for wildlife)
- Grassland Habitat
- Deer Wintering Habitat (evergreen forests that provide food)
- Travel Corridors
Natural Communities and Special Habitats
The Arrowwood documents, which highlight many types of forest habitat, are deeply detailed with numerous tables and descriptions. Charts that list acreages for specific forest types will allow community members and planners to better understand which species are available abundantly and which are limited. Natural communities that support rare elements, such as endangered species, can also be understood in a broader context. A greater understanding of the connectedness of all of the valley's land areas may be gained from a study of these inventories.
Timely subjects covered by the research include wetland natural communities. Study of the distribution patterns of vegetation in lower lying areas may help our community better understand what is needed in order to create stable floodplains over time. For instance, the species that comprise a Floodplain Forest can be identified and related to surrounding habitats.
Floodplain Forests are among many forest types described in Thompson and Sorenson's book entitled "Wetland, Woodland, Wildland: A guide to the Natural Communities of Vermont." Along with detailed information about numerous forest types, a description of pre-settlement Floodplain Forests is offered:
"The floodplain forests that occurred adjacent to the rivers in this region prior to European Settlement must have been spectacular...they were likely continuous bands of forest extending unbroken for miles along all of our major rivers. Forests of towering silver maple and American elm likely covered many of the active floodplains, with more diverse forests of sugar maple, red oak, and other species on higher terraces." (Thompson and Sorenson, 248)
Although modern day floodplain forests may not exist in exactly the same state as pre-settlement forests, understanding the dynamics of such environments may help inform decision-making today. Expanding our base of ecological knowledge and developing in-depth understanding of forest topics may help the community develop responsible land use guidelines.
The USDA maintains an excellent plant identification site available for citizens for non-profit/educational purposes at http://plants.usda.gov/java/ (Users of the site must use it in accordance with USDA policies). Forests are often a complex blend of habitat types, and the ability to recognize species mix and patterns across the landscape may allow for more thoughtful planning. An understanding of the unique attributes of various natural community types will also help viewers accurately interpret the Critical Habitat Unit maps.