Southern Vermont Arts Center
Ecological Analysis of Forest Lands
Elizabeth Thompson
Consulting Conservation Biologist
July 5, 2004
For
The Nature Conservancy
Southern Vermont Arts Center Ecological Analysis, E. Thompson. Page 1
Introduction and Methods
In May of 2004, together with Joan Allen of The Nature Conservancy, I visited the
forested portions of the property of the Southern Vermont Arts Center. The purpose of
the visit was to assess the ecological significance of the property from a local, statewide,
and ecoregional point of view.
We used the 1990 Use Value Appraisal Management Plan as the basis for our
investigations. That plan divides the forested portion of the property into nine areas
totaling 373.57 acres. We visited and evaluated each of the areas with respect to natural
communities, rare species, and forest condition. The results are summarized below.
Features of Ecological Significance
The property of the Southern Vermont Arts Center has considerable elevational diversity
(elevations range from 1100 feet to 3100 feet), geological diversity (including marbles
and phyllites), and topographical diversity (including streams, spring seeps, dry knolls,
gentle slopes, steep slopes, cliffs and summits). Hence, its biological diversity is high.
We found the following features of ecological significance, listed in order of importance:
1. Rich Northern Hardwood Forest, and part of a large, intact forested area
2. Five rare and Uncommon plants:
Loose sedge (Carex laxiculmis)
Yellow lady’s slipper (Cypripedium pubescens)
Purple clematis (Clematis occidentalis)
Poke milkweed (Asclepias exaltata)
Minnesota sedge (Carex albursina)
Rich Northern Hardwood Forest
The most important ecological feature of the Southern
Vermont Arts Center property is the extensive and welldeveloped Rich Northern Hardwood Forest Community
(photo right). Together with similar forested areas on
adjacent lands on the east slopes of Mount Equinox and
Mother Myrick Mountain, this natural community covers
approximately 2,000 acres. Region-wide analyses by The
Nature Conservancy show that this that this is probably the
largest and best-developed example of this natural
community in the northeastern United States. Following is a
general description of the Rich Northern Hardwood Forest,
adapted from Wetland, Woodland, Wildland: A Guide to the
Natural Communities of Vermont.
Rich Northern Hardwood Forests are quintessentially Vermont. Sugar maple is abundant in
these forests, making them vital to three of Vermont’s economic staples: maple sugar
production, forestry, and tourism. Rich Northern Hardwood Forests are places where colluvial
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processes (downslope movement) or mineral rich bedrock, or some combination of the two,
provide plants with a steady supply of nutrients.
Here organic matter and plant nutrients accumulate over time, forming a compost-like soil. If
the bedrock or till on such a slope is at all enriched with calcium and other key plant nutrients,
these will be washed from upper to lower slopes, giving the plants below the greatest
advantage. Productivity is high in these places, as is the overall diversity of plant species.
The upper slopes or the convex knobs on such a hill, where nutrients are leached from the
soils and moved away from plant roots, will probably have communities such as Northern
Hardwood Forest, Hemlock Forest, Mesic Red Oak-Hardwood Forest, or Dry Oak-HickoryHophornbeam Forest, with lower species diversity and lower productivity.
Overall, the soils in Rich Northern Hardwood Forests range from well drained to somewhat
poorly drained. Sometimes, there is a pan or restricting layer in the soil, generally about 1824” from the surface. This restricting layer can be a factor in keeping moisture and nutrients
near the surface, where they are more available to plants. Where soils are more moist,
productivity is higher, trees produce higher quality wood, and herbaceous plants are more
abundant.
Vegetation
Rich Northern Hardwood Forests are high productivity
forests: trees grow quickly, and they grow tall and
straight. Sugar maple is dominant in the canopy, but
basswood and white ash are common as well. The
shrub layer varies from almost absent in dense shade
to quite to well-developed in sunny openings. Herbs
are often abundant on the forest floor, forming a
continuous carpet of lush vegetation in mid summer.
Most of the herbs in these forests are long-lived
perennials, and many of them are “spring
ephemerals”; they flower and fruit early in spring,
before trees leaf out and when sunlight is plentiful. By
mid-summer, some of these plants, like Dutchman’s
breeches, have lost all their foliage and are completely
invisible at the surface. Other plants, like wood nettle
and maidenhair fern, persist throughout the summer,
displaying large canopies of leaves to gather the
filtered light on the forest floor.
The overall diversity of species is high, as is the sheer abundance of biomass on the forest
floor. Along with the trees mentioned above, some of the characteristic plants include wood
nettle, maidenhair fern (photos above and on cover), blue cohosh, wild leeks, Dutchman’s
breeches, Canada violet, wild ginger, bulblet fern, and Christmas fern.
Distribution and Abundance
This community occurs throughout Vermont at low to moderate elevations (to about 2500 ft).
It is most common where the bedrock is calcareous, but is also present in areas of
calcareous till or topographically induced enrichment.
This community occurs throughout the northeastern United States and adjacent Canada, but
is less common in our neighboring states. It usually occurs in small patches of 10-50 acres in
size.
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The Rich Northern Hardwood Forest on the Southern Vermont Arts Center is clearly of
region-wide significance and is therefore worthy of the highest level of conservation
available. Although this forest has been carefully managed and is therefore in excellent
condition, I believe its significance now warrants a no-harvest conservation approach,
which will ultimately lead to the presence of old growth forest on the property.
I justify this recommendation as follows:
Unmanaged forests function ecologically at the highest level. In unmanaged forests,
which ultimately achieve old growth characteristics, natural ecological process can
function unhindered by human activity. In the case of Rich Northern Hardwood Forests,
this means that downslope movement can proceed without the interruptions of forest
roads and other impediments; nutrients are cycled and remain completely within the
system rather than being removed, natural openings created by windfall create a diversity
of microhabitats, and soils are healthy and rich with a natural fauna of invertebrates and
microorganisms.
Unmanaged forests
contain biological
legacies not found in
managed forests.
Biological legacies
include down dead wood
(photo, right, on SVA
property), standing snags,
and other plant and
animal remains that
remain in the forest to
provide habitat for other
species.
Some species prefer old
growth forests.
Researchers in northeastern forests have identified certain mosses and liverworts that
seem to prefer old growth forest conditions. There may well be other species, particularly
insects and soil microbes, that can only survive in the undisturbed soils of old growth
forests. Although we know of no specific examples of species that require old growth
Rich Northern Hardwood Forests, it seems prudent to provide some of that specialized
habitat.
Old growth forests provide reference sites for ecological research. We have no way of
knowing what species need old growth or how Rich Northern Hardwood Forests function
without having a few sites where we can observe natural ecological process and study the
biota over long periods of time. Old growth forests provide a crucial scientific resource.
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In order to function fully, this natural community needs to be protected as part of a
larger conserved landscape where natural ecological processes can fully function. This is
the region’s best opportunity for large-scale conservation of this natural community. The
Rich Northern Hardwood Forest on the Southern Vermont Arts Center property is a part
of what may be the region’s largest and best-developed example of this natural
community. Because of this, and because the forests of Mount Equinox are generally in
excellent condition because of good forest management over many years, the area has
been identified by ecologists and by The Nature Conservancy as an ideal place to
conserve this natural community in a fully functional forested landscape. The work has
already begun: the property of Equinox Resort Associates is protected by a forever-wild
easement (held by the Vermont Land Trust) and The Nature Conservancy has purchased
parcels on Mount Equinox and Mother Myrick Mountain for the purposes of restoring old
growth forest. The SVA property, if conserved in similar fashion, would add a key
missing puzzle piece to this important natural area. If all the pieces come into place, the
mountain over time will achieve the characteristics of a wild landscape that has not been
seen in the northeast since the first settlers arrived here in the eighteenth century.
Rare and uncommon plants
We observed five rare and uncommon plants in our inventory. There may be others that
we did not see. The five are described briefly below:
1. Loose sedge (Carex laxiculmis) – This plant
(photo right) is rare in Vermont, found in the
rich forests of the Taconics and also in the
clay soils of the Champlain Valley. It is found
at the lower elevations (below 2000 feet) on
the property, in areas 3, 4, 5, and 6.
2. Yellow lady’s slipper (Cypripedium
pubescens) – This orchid, uncommon in
Vermont, is found occasionally in the rich
forests on Mount Equinox. We found it in the
open oak forest above the ledges in Area 5.
3. Purple clematis (Clematis occidentalis) – This plant is uncommon in Vermont. It
prefers dry, open, limy soils. We found it in the open oak forest above the ledges
in Area 5.
4. Poke milkweed (Asclepias exaltata) – This plant is uncommon in Vermont. We
found it in the open oak forest above the ledges in Area 5.
5. Minnesota sedge (Carex albursina) – This plant is uncommon in Vermont, found
only in very rich, loamy soils. We found it in several locations below 2000 feet
elevation.
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Description by Forestry Plan Area
Areas 1 and 2 (photo left) are the high-elevation areas,
characterized by Montane Yellow Birch-Red Spruce
Forest and Northern Hardwood Forest. These areas
give way to hardwood forest further downslope. Most
of this area does not contain Rich Northern Hardwood
Forest, but its conservation is important in protecting
the forest below, since downslope movement is one of
the key ecological processes in Rich Northern
Hardwood Forests.
Areas 3, 4, 5, and 6 (photo right)
are predominantly Rich Northern
Hardwood Forest, with some
areas of Red Oak-Northern
Hardwood Forest above the
ledges in Area 5. These areas are
the highest priority for long-term
conservation of this natural
community.
Summary of Recommendations
Areas 1, 2, 3, 4, 5, and 6: Provide long-term protection of these forests, allowing
maintenance of trails and removal of hazardous trees only, but no commercial timber
harvest.
Areas 7, 8, and 9: Maintain in forested condition, managing as needed to enhance
Boswell Botany Trail and to generate income from the removal of timber. To prevent the
spread of non-native exotic species, use single tree or small group selection silvicultural
methods.
About the Author Elizabeth Thompson is a private consulting conservation biologist whose training is primarily in
vegetation ecology and botany. She worked for The Nature Conservancy and led that organization in its conservation
planning for the Equinox Highlands. In this capacity she organized a group of foresters and ecologists to work together
in planning for the conservation of this important landscape. She also participated in The Nature Conservancy’s
ecoregional planning efforts, which identified the Equinox area as a high conservation priority regionally. As a private
consultant, she inventoried the properties of the Equinox Resort Associates. She advised the resort as they conserved
their property and developed a management plan. With Eric Sorenson, Thompson is co-author of Wetland, Woodland,
Wildland: A Guide to the Natural Communities of Vermont. Presently Thompson’s clients include the Vermont Land
Trust and The Nature Conservancy.
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