rapid assessment of dry oak woodland natural communities at
TRANSCRIPT
Rapid Assessment of Dry Oak Woodland Natural Communities at Merck Forest, Rupert Vermont
A Master’s Project Presented to the Environmental Studies Department
Antioch University Keene, New Hampshire
In Partial Fulfillment of the Requirements for the degree Master of Science
By: Heather O’Wril March 2012
© 2012
All rights reserved
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Acknowledgements
I would like to extend a heartfelt thank you to all the people who have helped to make
this project possible. Thanks to my supervisor, Peter Palmiotto for his guidance and
expertise from brainstorming project ideas to seeing it through to completion; thanks to
Tom Ward for his input and the Merck staff for their enthusiasm; thanks to Liz
Thompson, Eric Sorenson, and Melissa Coppola for their advice; thanks to my dog Ole
who was always by my side in the field, and a special thanks to Jack O’Wril whose
endless amounts of support kept me moving forward.
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Project Summary
Dry oak woodlands are ranked as a rare (S2) natural community in the State of Vermont,
but can be found at Merck Forest. The objectives of this project were to locate and assess
the ecological integrity of the dry oak woodlands at Merck so that the information can be
incorporated into the forest management plan and used for future educational and
research opportunities. Potential dry oak woodlands sites were located using overlapping
spatial data in a Geographic Information System. The vegetation assemblages of these sites
were then inventoried in the field. Out of the eleven sites, three contain dry oak woodland
communities, which range in size from 0.9 to 1.4 acres.
The dry oak woodlands’ ecological integrity was assessed using several metrics to
compare with an exemplary community type. Only one of the three sites was found to have
its ecological integrity intact. Management recommendations for each of the dry oak
woodland communities were made based on the site characteristics and species
composition with priority given to the community with the best ecological integrity. The
prescription with the greatest potential for successfully restoring and maintaining this
natural community type is a fire regime. A fire will assist in regenerating oak, recruiting
oak into the canopy, removing undesirable species, and opening up the canopy so that
sunlight can penetrate the forest floor to promote a grassy understory. Two important
questions left to be determined are: 1) whether fire is required to maintain dry oak
woodlands in New England? and 2) what fire regime will best maintain this community
type in New England?
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Table of Contents
PROJECT SUMMARY .............................................................................................................................. ii
INTRODUCTION ...................................................................................................................................... 1 Project Objectives ................................................................................................................................................................ 1 Merck Forest ......................................................................................................................................................................... 3
Land Use History ...................................................................................................................................................................... 3 Mission Statement ................................................................................................................................................................... 3
Natural Communities ......................................................................................................................................................... 4 Description .................................................................................................................................................................................. 4 Assessing Ecological Integrity ........................................................................................................................................... 6
Dry Oak Woodlands ............................................................................................................................................................ 6 Characterization ...................................................................................................................................................................... 7 Role of Fire .................................................................................................................................................................................. 8 Wildlife Potential ..................................................................................................................................................................... 9 Recreation Potential............................................................................................................................................................ 10 Research and Education Potential ............................................................................................................................... 11
Management Prescriptions for Dry Oak Woodlands ......................................................................................... 11 Prescribed Fire ....................................................................................................................................................................... 12 Mechanical Cutting .............................................................................................................................................................. 14 Herbicide Application ......................................................................................................................................................... 15 Planting ..................................................................................................................................................................................... 15 Controlling or Eliminating Deer Browse ................................................................................................................... 16
METHODS ............................................................................................................................................... 17 Site Description ................................................................................................................................................................. 17 Remote Mapping of Potential Dry Oak Woodland Sites ................................................................................... 17 Field Data Collection ....................................................................................................................................................... 18
Rapid Assessment .................................................................................................................................................................. 19 Detailed Site Inventory ....................................................................................................................................................... 19
Data Analysis ...................................................................................................................................................................... 20
SITE ANALYSIS ...................................................................................................................................... 22 Vegetation ........................................................................................................................................................................... 23
Red Spruce Northern Hardwood Forest (site 1&2) ............................................................................................... 23 Northern Hardwood Forest (Sites 3-8) ....................................................................................................................... 25 Mesic Red Oak Northern Hardwood Forest and Dry Oak Woodland (sites 9-11) .................................. 25
Soils ........................................................................................................................................................................................ 26 Landscape ............................................................................................................................................................................ 27
DRY OAK WOODLAND ANALYSIS ................................................................................................... 29 Vegetation ........................................................................................................................................................................... 29
Site 9 ........................................................................................................................................................................................... 29 Site 10 ......................................................................................................................................................................................... 34 Site 11 ......................................................................................................................................................................................... 37
Soils (MRONHF vs DOW) ............................................................................................................................................... 41 Landscape (DOW 9-11) ................................................................................................................................................ 43 Ecological Integrity .......................................................................................................................................................... 43
Dry Oak Woodland 9 ........................................................................................................................................................... 43
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Dry Oak Woodland 10 ........................................................................................................................................................ 44 Dry Oak Woodland 11 ........................................................................................................................................................ 45
Specific Management Recommendations ................................................................................... 46 Dry Oak Woodland 9 ....................................................................................................................................................... 47 Dry Oak Woodland 10 .................................................................................................................................................... 48 Dry Oak Woodland 11 .................................................................................................................................................... 49
Conclusion ............................................................................................................................................. 51
Maps ......................................................................................................................................................... 52
References ............................................................................................................................................. 58
Appendix ................................................................................................................................................ 62
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List of Figures Figure 1. Picture of Vermont with the dry oak woodland community range highlighted in green
picture taken from Thompson and Sorenson’s Guide to the Natural Communities of Vermont, 2005……………………………………………...…………………………..6
Figure 2. Photograph depicting exemplary characteristics of a dry oak woodland at Merck,
Rupert, VT……………………………………………...………………………………8 Figure 3. Average density of seedlings per acre (± 1 Standard Error) for each species in the
mesic red oak-northern hardwood forest and dry oak woodland community of Site 9……….………………………………………………………………………….30 Figure 4. Average density of saplings per acre (± 1 Standard Error) for each species in the mesic
red oak-northern hardwood forest and dry oak woodland community of Site 9……………….………………………………………………………………….30
Figure 5. Mean percent cover of the substrate and vegetation of the forest communities at Site 9. ……………………………………………………………………………..…..33 Figure 6. Average density of seedlings per acre (± 1 Standard Error) for each species in the
mesic red oak-northern hardwood forest and dry oak woodland communities of Site 10. ………………………………………………………………………………..34
Figure 7. Average density of saplings per acre (± 1 Standard Error) for each species in the mesic
red oak-northern hardwood forest and dry oak woodland community of Site 10……………….………………………………………………………………...34
Figure 8. Mean percent cover of the substrate and vegetation of the forest communities at
Site 10..…………………………………………………….………………….………37
Figure 9. Average density of seedlings per acre (± 1 Standard Error) for each species in the mesic red oak-northern hardwood forest and dry oak woodland community of Site 10………………………………………………………………………………....38
Figure 10. Average density of saplings per acre (± 1 Standard Error) for each species in the
mesic red oak-northern hardwood forest and dry oak woodland community of Site 11.……………………………………………………………………………..….38
Figure 11. Mean percent cover of the substrate and vegetation of the forest communities at Site 11……….…………………………………………………………………….…..41
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List of Tables Table 1. The natural community type, its size and the total basal area at each Site……………24
Table 2. Importance Value percentage for each species at each site with dominant species highlighted in yellow………………………………………………………………….25
Table 3. Mean percent cover (± 1 Standard Error) of the substrate and vegetation of the forest communities at Site 9………………………………………………………………….32
Table 4. Mean percent cover (± 1 Standard Error) of the substrate and vegetation of the forest communities at Site 10………………………………………………………………...36
Table 5. Mean percent cover (± 1 Standard Error) of the substrate and vegetation of the forest communities at Site 11………………………………………………………………...40
Table 6. Average depth in centimeter (± 1 Standard Error) of soil the DOW and MRONHF communities of Sites 9-11…………………………….……………………………….42
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List of Maps Map 1. Location of Merck Forest in context of the state of Vermont and the town of
Rupert………………………………………………………………………………….…52
Map 2. Trail map for Merck Forest and Farmland Center in Rupert Vermont…………...……..53
Map 3. Dry oak woodland potential sites based on topography and southern aspect...…......…..54
Map 4. Sampling method depicting points and transects at each of the eleven sites and three oak woodland communities…………………...……………………………………………..55
Map 5. Soil types at each of the 11 potential sites at Merck Forest. Data taken from Natural Resource Conservation Service (NRCS) soil survey…………..……..………………...56
Map 6. Location of future controlled burn.……………………………………………….…......57
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Introduction
Dry oak woodland communities are rare (S2) in the state Vermont but can be found at
Merck Forest and Farmland Center (MFFC). Dry oak woodlands provide valuable habitat
as well as a nutritious food source for wildlife. They are also popular hiking destinations
due to the inviting conditions of an open canopy, grassy understory, and great views. The
occurrence of these significant natural resources can be seen as an asset to Merck.
The rare status of dry oak woodlands in Vermont makes them an important
community type to preserve, especially for those species that may rely on them for food
or shelter. Protecting rare habitat acts as a coarse filter for conserving species diversity.
Species are declining at a rapid rate. In the United States alone the number of species
listed as threatened or endangered under the Endangered Species Act (ESA) has
increased six fold from 174 in 1976 to 1244 as of November 2001 and the list gets longer
worldwide (U.S Fish and Wildlife Service). Habitat loss and degradation are the leading
culprits in the loss of diversity and many decisions resulting in such losses occur at a
local level (Dale et al. 2000). Therefore the rare communities at MFFC are of great
ecological significance and should be treated and recognized accordingly.
Project Objectives
The primary objective of this project is to provide pertinent information on the locations
and ecological integrity of the rare natural communities of Merck as well as providing
management recommendations aimed at conserving these resources. While the main
objectives are conservation-focused there are several ways in which Merck Forest can
benefit from this project. It is an exciting time at Merck Forest because the organization
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has been reviewing its assets so that they can be included in a new strategic plan as well
as a forest management plan that will be used to guide management decisions.
Documentation on the dry oak woodland communities will provide Merck with the
information to make informed management decisions, educate the public, and provide
baseline data for future research. A summary of the benefits to Merck is as follows:
1) Management Decisions: Information gathered in the rapid assessment can be used
to make informed management decisions. Although a full forest inventory will
be performed prior to writing the management plan, a timber cruise is unlikely to
provide detailed information about rare plant communities. Also, since Merck is
a demonstration forest these management decisions are a model for others to
emulate and therefore a complete site assessment is prudent.
2) Education: The strong educational programs at Merck are a wonderful resource to
teach people about the natural world. Rare natural communities have the
potential to be a one of a kind outdoor classroom, which in turn could be used to
draw a greater number of visitors to Merck. However, precautions to minimize
visitor impacts to the rare and sensitive plant communities should be taken into
consideration.
3) Future Research: The numerous unique features and expanse of land make Merck
an ideal place to conduct research. The data collected from this project will
provide a baseline for future research on dry oak woodland communities.
Merck Forest
Merck Forest and Farmland Center is a non-profit environmental education organization
located in Rupert, Vermont in the Taconic mountain range. It is 3160 acres of forest and
farmland and has 30 miles of trails that are open to the public for recreational activities.
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Land Use History
Merck forest has a strong land use history that can be seen by the numerous stonewalls,
barbed wire fences, cellar holes, and abandoned farming equipment on the property.
Although the landscape today is 93% forested, at the height of the sheep farming era, in
the 1930’s, two thirds of the land was cleared for hay and pasture with hundreds of sheep
roaming the hillsides (Cogbill, Merck Brochure). In 1950 George Merck bought these
abandoned farms to create what is now Merck Forest and Farmland Center.
Mission Statement
George Merck founded the Merck Forest and Farmland Center with the intention of
educating the public on land use practices that incorporated both a reverence for the
historical relationship to the land while fostering room for growth and experimentation
with new methods and technologies. The mission is to teach and demonstrate the benefits
of innovative, sustainable management of forest and farmland. My project focuses on the
forests at Merck where management practices include timber harvests, wildlife habitat
management and preservation, and sap production.
While Merck is a working forest landscape with active management operations to
improve timber quality, wildlife habitat, and sap production, there is also concern for
protecting the rare natural resources for the sake of preserving or even enhancing
biodiversity. Jack O’Wril, the forester on staff at Merck, is in the process of updating the
forest management plan and seeks additional data on rare plants or communities. I found
documented occurrences of the rare dry oak woodland natural community at Merck
(Thompson and Sorenson 2005, Olsen 2002), but could not find detailed records of their
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locations, sizes, or ecological integrity. It became clear that a project that incorporates
these details would compliment Merck’s mission and provide the opportunity to
understand this community type better. Including this information in the forest
management plan will help to ensure the protection of these community types in the
future.
Natural Communities
Description
A natural community is “an interacting assemblage of organisms, their physical
environment, and the natural processes which affect them” (Thompson and Sorenson,
2005). Natural communities develop in the absence of major disturbances on “ecological
sites”. Definitions for ecological site types have varied over time and across disciplines
(Leonard et al. 1992). Leak (1982) characterizes an ecological site type by its primary
physical attributes (geographic location, climate, soils and hydrology) and its biological
attributes (such as forest cover type and age class). He goes on to state that, “ecological
site types provide a basis and framework for understanding that while a species is capable
of growing on a variety of sites, the chances of it growing is related to its ability to
compete with other species on each particular site, and its development varies from site to
site.” Olson (2002) gives an example of a site type as a convex landscape with southwest
facing slope where the soils are warm and drought prone, and short, poorly formed oak
(Quercus L.), hickory (Carya Nutt.), red maple (Acer rubrum L.) and hop-hornbeam
(Ostrya virginiana Kosh.) are likely to be found. These tree species have evolved to
compete better than other species in warm, dry conditions.
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Natural communities are a logical unit for classifying and mapping land that is an
essential part of developing management or conservation plans. Categorizing natural
communities is also a tool for understanding the complexity and diversity of the
landscape. Natural communities occur in a wide range of sizes categorized as matrix
(1,000-100,000 acres), large patch (50-1,000 acres), and small patch (less than 50 acres).
Sometimes it is possible to easily distinguish the edge of one natural community and the
start of another; in other places they will grade into one another. There is also variation in
community structure and species composition within the concept of a natural community.
Northern hardwood forests are a good example because they are widespread and
extremely variable. Four variants of a northern hardwood forest are recognized within
this community type.
Natural communities usually describe landscapes that have developed over time
and have not experienced significant natural or anthropogenic disturbances. Therefore,
the focus is on mid- to late-successional forests and may exclude sections of the
landscape. It is important to note that these natural communities are not static because
species distributions shift across the landscape in response to climate change and
disturbance regimes (Thompson and Sorenson 2005).
Assessing Ecological Integrity
Assessing the ecological integrity of the target natural community was an essential
component of this project because it not only informs resource managers of the
condition but also reveals potential threats. “Integrity” is defined as the condition of
being unimpaired, sound, or complete. Ecological integrity has been used as a
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measure of the composition, structure, and function of an ecosystem in relation to
the system’s natural or historical range of variation, as well as perturbations caused
by natural or anthropogenic agents of change (Parrish et al. 2003). Tierney et al
(2009) illustrates that the first step in determining ecological integrity is identifying
a limited number of metrics that best distinguish a highly impacted or degraded
state from a relatively unimpaired, complete, and functioning state. He also
mentions that the metrics should be comprehensive enough to incorporate
composition, structure, and function of an ecosystem.
Dry Oak Woodlands
Dry oak woodlands are a rare community type in the state of Vermont because their
range is small and so is the size of the individual communities. They are locally common
in the Taconic Mountains, and there are scattered occurrences on the Cheshire Quartzite
in the Champlain valley (Figure 1). These woodlands tend to be smaller than 20 acres in
extent.
Figure 1. Picture of Vermont with green areas highlighting the dry oak woodland community range within the state. Taken from Thompson and Sorenson’s Guide to the Natural Communities of Vermont 2005.
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In addition to being rare, dry oak woodlands are a poorly understood natural
community. A literature search resulted in a few studies found on oak woodlands in the
western US, and very little information relevant to the New England region. It is difficult
to make comparison or inferences on the dry oak woodlands of the western US to those
of New England because the forest ecosystems and species composition are different.
Characterization
The best source of information on dry oak woodlands in New England is from Thompson
and Sorenson (2005). They describe this community type as having excessively drained
acidic soils, an open canopy dominated by short, poorly formed oak species spaced at a
distance with a scattering of shrubs and understory trees, and a ground layer dominated
by sedges, grasses, heaths, oak seedlings, forbs, mosses, exposed bedrock, and bare
ground (Figure 2). These sites are often located on the southern slopes of mountains or
hilltops and ridges and tend to be smaller than 20 acres in extent. The Wisconsin
Department of Natural Resources Website it mentions that dry oak woodlands occupy a
position on the vegetation continuum that is intermediate between oak savannas and oak
forests. Therefore, related community types in New England include dry oak forests
which tend to have similar species composition but with a closed canopy and taller trees.
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Figure 2. Photograph depicting exemplary characteristics of a dry oak woodland at Merck Forest in Rupert, VT.
The Role of Fire
Fire appears to have a significant impact on dry oak woodlands. Abrams (1992) states
that the distribution of oak reflects a variety of ecological paths and disturbance
conditions such as climate change, logging, animal and insect grazing, and disease, but
considers the historical changes influenced by fire to be the most significant contributor.
High-frequency fire regimes have been credited with creating and maintaining savannas
and woodlands in temperate North America prior to and during Euro-American
settlement (Paterson and Reich 2001, Anderson et al. 1999, McPherson 1997). The fire
prevention and suppression activities in recent years have lead to significant structural
changes including increase in tree density, basal area, and canopy cover (Fabor-
Langendoen and Tester 1993, Abrams 1992) and succession toward fire sensitive and
shade tolerant species such as sugar maple (Abrams, 1992).
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Oaks are highly adapted to the nutrient-poor, droughty conditions characteristic of
oak woodland communities and are prone to fire exposure. They are well suited for
droughty conditions due to deep roots, xeromorphic leaves, low water-potential threshold
for stomatal closure, and the ability to adapt osmotically and maintain high rates of
photosynthesis during a drought (Abrams 1990). Fire adaptations of oaks include thick
bark, ability to sprout, resistance to rotting after scaring, and the prime seed germination
conditions created after a fire (Lorimer 1985). Fire tends to favor oaks especially since
many of the later successional species such as red maple and sugar maple (Acer
saccharum Marsh.) have a much lower resistance (Abrams, 1992). Oaks have an
intermediate tolerance for shade, and therefore their seedlings do not exhibit long-term
survival or growth in a closed understory (Crow 1988). The understory species in oak
woodlands such as lowbush blueberry (Vaccinium angustifolium Aiton.), grasses, and
black huckleberry (Gaylussacia bacata Kosh.) are also well adapted to frequent fires.
Wildlife Potential
Dry oak woodlands provide unique habitat for a variety of animals that take advantage of
the open canopy and grassy herbaceous understory, the excellent food source from both
hardmast and softmast species, and the abundance of coarse woody debris (CWD) and
snags. Due to the rare occurrences of this community type protecting these areas can act
as a coarse filter for protecting species diversity. However, additional wildlife studies in
these community types would provide better insight into the best management practices
for these areas.
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Several studies done on oak woodlands stress the importance of an open canopy and
grassy understory to a variety of bird species (Hagar and Stern, 2001, Hunter et al. 2001).
Noss et al (1995) considers oak dominated woodlands in eastern North America to be a
critically endangered habitat. Hunter et al (2001) found that about 70% of 21 featured
species associated with open woodlands and savannas are undergoing long-term declines
or are declining recently in eastern North America. Many of the bird species that occur in
shrub-scrub and grassy dominated habitats can also be found in open woodlands. The
uncommon birds encountered in the dry oak woodlands of Vermont include tufted
titmouse and yellow-billed cuckoo (Thompson and Sorenson, 2005).
Despite the poor soils and rocky steep terrain that characterize dry oak woodlands
they provide a good source of food to a variety of wildlife. The dominant oak canopy
provide hardmast in the form of acorns which are consumed by squirrels, bear, turkey,
and deer. White oak (Quercus alba L.) is a common component of oak woodlands and
provides an easily digestible and nutritious acorn crop because they mature in one year
unlike red oak (Quercus rubra L.), which takes two years, and they contain fewer
tannins. While white oak was not present in the sample survey at Merck, there is the
possibility to introduce or reintroduce it at these sites. Small mammals and birds can feast
on the soft mast of the blueberries, black huckleberries, and shadbush (Amelanchier
Medik.) berries.
Snags and coarse woody debris (CWD) provide important structure to a forest for
wildlife. Dry oak woodlands tend to have a higher concentration of snags and CWD due
to the shallow soils, steep slopes and harsh conditions. Snags and CWD have a variety of
functions as food or shelter depending on the amount of decay and size class. For
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instance, birds of prey will sit on the high branches of a dead tree to search for prey;
woodpeckers will excavate a hole into a tree to nest when the central column of the trunk
begins to decay: Ants, grubs and several reptiles and amphibians will eat or find refuge in
wood only after it has become punky and soft. Ringed-necked snakes are known to spend
days under the decaying debris in dry oak woodlands (Thompson and Sorenson 2005).
Recreation Potential
Dry oak woodlands are a great place to have a trail destination because the open canopy
provides good views from the top of hills, ridges and mountains. At the top of Mount
Antone, the highest peak and the most popular hike at Merck, there is a small dry oak
woodland. It is a grassy picnic spot with short, widely branching oaks and a panoramic
view of the landscape. Visitors like to take naps under the shade of the oaks in the
summer time and warm their faces in the sun in the winter. I did not include this spot as
part of my project survey because humans seeded the grass and it was less than 100 feet
in size. However, the other dry oak woodland communities at Merck are also near
walking trails and frequented by visitors for its inviting qualities and scenic vistas.
Research and Educational Potential
The accessibility of the dry oak woodland communities and their unique qualities make
them a great spot to educate the public about the rare natural resources at Merck and to
conduct research to understand them better. Educational opportunities could come in the
form of information sessions, interpretive signs, or land stewardship activities to protect
and enhance these areas such as treating weeds or recruiting snags and CWD for wildlife.
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Since dry oak woodlands are not well understood additional research will be
important to increase our understanding of their structure and function so that the best
management practices can be implemented. One of the great unknowns about this
community type is whether fire is required to maintain them (Thompson and Sorenson
2005) and if so what type of fire regime is needed. The baseline information provided
from this project can be used for future research.
Management Prescriptions for Dry Oak Woodlands
A common theme in dry oak woodland degradation is the problem of regenerating oak
species. The eventual senescence of the overstory trees coupled with the lack of oak
regeneration leads to the loss of these ecosystems (Brudvig and Asbjornsen 2005).
Therefore, restoration efforts in oak woodlands and savannas, especially in the Mid-West,
have been of particular interest to many forest research efforts (Brudvig and Asbjornsen
2005, Peterson and Reich 2001, Abrams 1992, Tester 1989).
Brudvig and Asbjornsen (2005) found that a bottleneck can exist between the oak
seedling and sapling stage of development. They consider a canopy thinning to be a
necessary step toward restoring oak savanna because without additional sunlight the
seedlings cannot grow. Buckley et al (1998) raises the concern of interspecific
competitors that have become more prominent with the suppression of fire not only in the
canopy but the understory and shrub layers too. Their study shows that while removing
potential competitors has a positive effect on the growth of oak seedlings, it also leads to
increased deer browse and frost damage, which can compromise the integrity of the site.
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Enhancing oak regeneration and restoring the species composition to a grass and
blueberry dominated understory is the main concern in restoring and maintaining dry oak
woodlands. Brose et al. (2008) provides treatments options to regenerate oak in the Mid-
Atlantic region that can be used to guide oak regeneration efforts in New England as
well. Due to the harsh conditions and steep slopes it is not advisable to use heavy
equipment. The active treatments that are suggested include: 1) Prescribed fire, 2)
mechanical cutting, 3) the application of herbicide, 4) planting 5) and controlling or
eliminating deer browse.
Prescribed Fire
A prescribed burn is the best restorative method for a dry oak woodland site because it
not only removes competition, but also creates favorable conditions for acorn catching
and seed germination, reduces the population of predatory insects, and creates xeric
conditions in which oak is a top competitor. Fire creates favorable seedbeds for oak to
germinate by burning the accumulation of leaves and twigs on the forest floor and
exposing mineral soil. It is well documented that oak tends to regenerate well on xeric
sites (Sanders 1988) The increased in oak germination success rate in scarified mineral
soils because freshly germinated seedlings are unable to emerge through a heavy litter
cover (Van Lear and Watt 1992) and because squirrels and blue jays prefer exposed soil
to bury their acorns (Galford et al. 1988). Oak seedlings can survive a fire even if their
tops are killed as long as they have developed an extensive root system (Van Lear and
Watt 1992). The ability of oak to germinate and to resprout following a fire gives the
species an advantage over others in these conditions.
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Fire patterns and frequency are important factors to consider. “Long-term
persistence of savanna or open oak woodland sites requires that a dynamic balance be
maintained between mortality and ingrowth, such that neither trees nor grasses become
locally extinct” (Peterson and Reich 2001). While experimentation is still needed to
determine the best fire regime for oak woodland restoration (McPherson 1997) annual to
biennial fires are thought to produce the most rapid reduction in tree canopy density
(Peterson and Reich 2001, Faber-Langendoen and Davis 1995). Peterson and Reich
(2001) suggest setting up a frequent fire regime to decrease overstory tree density and
basal area, eliminate or suppress understory trees and shrubs, and facilitate the
development of a continuous herbaceous layer dominated by grasses. Once these
objectives are met the fire regime can be adjusted to be less rigorous in order to maintain
the structure and composition.
Prescribed fires are less common in New England than other regions of the United
States due to the wet conditions and high density of development. Thompson and
Sorenson (2005) recommend leaving areas where dry oak woodlands occur free from
structures so that there is the option of using fire as a restoration or management tool
without threatening human property. The window for burning is short due to the many
factors that must be met in order for the treatment to be successful as well as safe. Fast et
al. (2008) came up with a compilation of parameters taken from the results of several
burns done across New England. They consider weather, fuel type, fuel characteristics,
fire application, soil, vegetation, time, and a fire danger rating system to be the important
factors in determining when a prescribed fire is recommended. The weather is especially
important and may be limited by factors such as air temperature, relative humidity, wind
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speed, wind patterns, and time since the last rain. Therefore, it may be difficult to carry
out the desired number of burns within a certain time period and mechanical cutting
would be a possible substitute.
Mechanical Cutting
Mechanical cutting is a good technique for restoring a site that can’t be burned or used in
conjunction with a burn to assist in the removal of competition from undesirable tree and
shrub species. Since dry oak woodlands tend to be small in size (Thompson and Sorenson
2005) it is possible to use hand tools such as chainsaws, pruning saws, axes, or clippers to
do the work. The sites should be managed for red oak and a ground layer dominated by
grasses and blueberry. Removing trees and shrubs competing with the dry oak woodland
vegetation will help to maintain the site. The removal of weeds and invasive plants (if
they appear) will alleviate the competition in the understory. Mechanical cutting may
speed up the restoration process if used in conjunction with a burn because species that
have become resistant to fire can be taken out.
Herbicide Application
The application of herbicide is another method for removing or controlling both canopy
or ground vegetation. It is a useful method for controlling species that sprout back or tend
to spread quickly. Possible methods include Cut and Spray for undesirable woody species
that are mixed in with the regeneration; Stem Injections used to treat trees with a diameter
at breast height (DBH) greater than 2’’; Basal Application for trees with a DBH less than
2’’; and Cut Stump for species that are resilient sprouters (Brose et al. 2008).
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The disadvantage to using herbicide is the risk of damaging non-target species.
Using an herbicide with glyphosate will help to minimize this risk. Herbicide application
should not be used on sites that are near a potential sugarbush because this practice is
against organic certification rules for producing maple syrup. It is advisable to avoid
recreational trails so that pets and visitors are not in contact with the herbicide.
Planting
In order to get the desired species composition it may be helpful to plant or scatter seeds
of some of the dry oak woodland species especially after a disturbance such as a burn or
mechanical cutting. The sites with low levels of blueberry or grass coverage may benefit
most from an additional seed source. It is important to provide optimum conditions for
the seeds to thrive, which in the case of oak means exposed mineral soil.
Controlling or Eliminating Deer Browse
While signs of deer browse were present in the dry oak woodlands at Merck, it did not
appear to be the most important factor limiting the regeneration of oak or the loss of dry
oak woodland vegetation. However, controlling or eliminating deer from a dry oak
woodland site may help to alleviate stress and boost the ecological integrity of the site.
This can be done by instituting aggressive hunting measures, putting up a fence, or
leaving logging slash behind to protect the vegetation.
Fences are a better way of ensuring that deer stay off the site, but require more
time and resources. Brose et al. (2008) recommends using a woven wire fence because it
will last for several decades. The fence should be put up around the perimeter of the dry
17
oak woodland and would require routine inspection and occasional maintenance. The
decision to put in a fence should take into consideration the wildlife that may become
restricted.
Another solution to keeping deer from eating the dry oak woodland vegetation is
to leave slash at the site after a timber harvest. The debris restricts the access and helps to
protect oak regeneration as well as other species that are preferred (Perkins and Mautz
1987). This may take away from the open savanna feeling for visitors and restrict human
movement, but in the long run it would help to protect the site. It may also be difficult to
establish enough slash to be effective since the basal area tends to be lower in dry oak
woodland forests. Additional research on the intensity of deer browsing or other potential
predator in the dry oak woodlands at Merck can help managers make more informed
decisions.
18
METHODS
Site Description
Merck Forest and Farmland Center is located in Rupert, Vermont in the Taconic
Mountain Range (Map 1). It is 3160 acres in size. Rupert is in southwestern Vermont in
the northern limits of Bennington County. Rupert shares a boundary with Pawlet to its
North, Danby touches the northeastern corner, Dorset to the east, Manchester in the
southeastern corner, Sandgate to the South, and upstate New York to the west.
The main entrance to Merck is off of route 315, but there is also a south gate
entrance off Hidden Valley Road (Map 2). Old Town Road is the main road through the
middle of the property, but there is a total of 30 miles of roads and trails. The elevation
ranges from ~1000’ at the southern end of the property to 2600’ at the top of Mount
Antone. The bedrock is made up of metamorphosed mudstones that originated in the
Cabrian and Ordovician time and were later thrust westward during the Taconic Orogeny
to land far from its place of origin on top of Ordovician limestones (Thompson and
Sorenson 2005). The landscape at Merck is composed of a diversity of rolling hills,
bubbling creeks, fields and pasture, and second growth forest.
Remote Mapping of Potential Dry Oak Woodland Sites
The first part of my project involved identifying the target natural community and then
creating maps of potential sites where the target was likely to be found. I chose to focus
on the Dry Oak Woodland natural community because they are the only natural
community ranked as rare (S2) by the state of Vermont that is known to be present at
Merck. Thompsons and Sorenson’s natural community guide to Vermont—Wetland,
19
Woodland, Wildlands— was the main resource used to define the natural communities
and their characteristics.
The potential oak woodland site map was created in ArcMap10.0. Spatial data
taken from the Vermont Center for Geographic Information (VCGI) website was used to
create a base map using the following overlapping layers: Merck property boundary,
aerial photograph, roads, streams, and digital elevation model (DEM) data to produce
contour lines and hillshade to highlight the southern exposed aspects. Identification of the
important oak woodland land features were taken from Thomposon and Sorenson’s
natural community guide mentioned above and included the areas where hilltops,
mountaintops, or ridges overlapped with a dry south-facing slope. Polygons were made in
ArcMap to highlight with green the eleven sites that contained the promising dry oak
woodland features mentioned above (Map 3).
Field Data Collection
The second portion of the project was broken into two parts: a rapid assessment and a
detailed site inventory. The rapid assessment was done to locate the actual oak woodland
sites from the eleven potential sites mapped remotely. The rapid assessment data
collection was done during the months of July through September 2011 and the site
inventory was done in October and November 2011.
20
Rapid Assessment
The rapid assessment was done by creating a systematic grid of sample points in each
potential dry oak woodland site using Hawth’s tools in ArcMap (Map 4). The points were
located using a handheld garmin (Dakota 20) GPS. At each point an angle gauge with a
basal area factor of 10 was used to select the trees to tally. The data recorded included the
basal areas of tree species greater than 4” diameter at breast height (DBH). Data was not
collected at points where a recent timber harvest had been conducted. A qualitative site
analysis was also done to record soil characteristics, slope, presence of invasive species,
rare plants, or other notable landmarks. From the basal area data and qualitative site
analysis I was able to identify three dry oak woodland natural communities and delineate
their boundaries using a handheld GPS and flagging tape.
Detailed Site Inventory
Once the three dry oak woodland communities were delineated additional data was taken
to compare the dry oak woodland communities to the adjacent mesic red oak-northern
hardwood forest communities at Sites 9, 10, and 11 (Map 4). Line transects in addition to
more points were generated in ArcMap and used to sample the vegetation in both natural
communities. The transects and points in the mesic red oak-northern hardwood forest
were set up 100 feet from the edge of the dry oak woodland at each site. Points and
transects were located using a handheld GPS.
There were five points in each community used to collect tree sapling data.
Saplings were defined as being taller than one meter and less than 4” DBH. Sapling
species were counted within an 11.7 ft radius plot delineated with a string the length of
21
the radius attached to a tent stake. The five points in the dry oak woodland communities
were also used to collect data on the basal areas using the same variable radius plot
method used in the rapid assessment.
There were three to four transects in the dry oak woodlands and two to three
transects in the mesic red oak-northern hardwood forest set up to collect data on the
vegetation and substrate cover, seedling density, and soil depth (Map 4). The transects
locations were selected in ArcMap by making two points 50ft apart, and then in the field
a measuring tape was placed on the ground between the points. A 3.7ft quadrate was
placed every five feet along the measuring tape starting on the right side and alternating
sides. R.F. Daubenmire’s plot sampling protocol was used to select the items to sample
and cover classes for measuring the percent of vegetation and substrate. Soil depths were
taken in the middle of each plot using a 45cm stake and a plastic flexible ruler. Tree
seedlings were defined as being everything smaller than 1 meter. Tree seedlings species
were counted per stem as well as given Daubenmire’s percent cover class.
Data Analysis
The quantitative data was compiled into Microsoft Excel and then displayed as
graphs and tables. Outputs include species composition of each stand based on the
Importance Value, number of saplings per acre, number of seedlings per acre, percent
cover of vegetation and substrate, and soil depth. A non-parametric Wilcoxen rank-sum
statistical test was preformed on the percent cover of vegetation and grass, as well as the
soil depth between the dry oak woodland and the mesic red oak northern hardwood forest
community. The graphs, tables, and statistical analysis as well as the qualitative data was
22
used to characterize the communities, assess the ecological integrity of the dry oak
woodlands, and provide management recommendations for the dry oak woodlands.
The Importance Value (IV) is used to determine the relative dominance of living
tree species present within a given area. The importance value is the sum of the species
relative cover, relative density, and relative frequency (Brower et al. 1998). To be able to
calculate the relative density, the diameter at breast height is required. The sampling
method used for this project did not include taking DBH measurements in order to
increase the speed of data collection. Thus, the relative density was not included in the
calculation and the IV was equal to the sum of the relative cover and relative frequency.
A summary of the calculations is as follows:
• Cover = number of each tree species X 10 (Basal Area Factor)/ total number of sampling points at the site.
• Frequency = Species points of occurrence/ total number of sampling points at the site
• Relative Cover = Species Basal Area/ Total Basal Area
• Relative Frequency = Species frequency/Total Frequency
• IV= Relative Frequency + Relative Cover
• IV as Percentage = IV/2
The dry oak woodland’s ecological integrity was assessed based on three criteria: 1)
the size and shape of the community, 2) whether the community met the site
characteristics described in the definition of a dry oak woodland, 3) and the severity of
potential threats or human disturbances. Comparisons were made between the dry oak
woodlands at Merck and the definitions of an exemplary community.
23
Site Analysis Out of the eleven potential sites only three of them were actual dry oak woodland
(DOW) natural communities (Table 1). Sites 9, 10, and 11 contained DOW
communities ranging in size from 0.9-1.4 acres. The forest surrounding the DOW is
mesic-red oak northern hardwood forest (MRONHF). Sites 1 and 2 are the red
spruce northern hardwood forests and Sites 3-8 are northern hardwood forest. It
should be noted that the DOW was the only community type to be delineated
according to forest type where as the others were analyzed by Site and may actually
contain a few community types.
Vegetation
Red Spruce Northern Hardwood Forest Community (Sites 1 & 2) The red spruce northern hardwood forest community was present at Site 1 and 2 located
in the northern portion of the property. Sites 1 and 2 totaled 26.3 acres ranging in size
from 9.2 to 17.1 acres. The dominant tree species at Site 1 and 2 was red spruce (Picea
rubens Sarg.) (Table 2). There was a significant presence of grey birch (Betula
populifolia Marsh.) and red maple at both sites, and hop-hornbeam and sugar maple at
Site 2. There were no signs of a dry oak woodland at Site 1 or 2.
24
Table 1. The natural community type, its size (acres), the total basal area (ft 2/acre), the landform type, and elevation (feet) at each site. Merck Forest: Rupert, VT. Site Natural Community Type Abbreviation Size Basal Area Landform Elevation
1 Red Spruce Northern Hardwood Forest RSNHF 9.2 148.0 Mountaintop 2200
2 Red Spruce Northern Hardwood Forest RSNHF 17.1 120.0 Slope of Hill 1900
3 Northern Hardwood Forest NHF 85.2 125.4 Ridge 2500
4 Northern Hardwood Forest NHF 24.0 110.0 Ridge 2300
5 Northern Hardwood Forest NHF 48.5 109.6 Ridge 2400
6 Northern Hardwood Forest NHF 17 128.3 Mountaintop 2600
7 Northern Hardwood Forest NHF 54.6 97.0 Ridge 2100
8 Northern Hardwood Forest NHF 20.3 80.0 Spur Ridge 2000
9 Mesic Red Oak-Northern Hardwood Forest MRONHF 14.5 141.4 Spur Ridge 1700
9 Dry Oak Woodland DOW 1.4 120.0 Spur Ridge 1700
10 Mesic Red Oak-Northern Hardwood Forest MRONHF 16.1 125.0 Spur Ridge 1900
10 Dry Oak Woodland DOW 1.4 115.0 Spur Ridge 1900
11 Mesic Red Oak Northern Hardwood Forest MRONHF 32.4 123.1 Spur Ridge 2400
11 Dry Oak Woodland DOW 0.9 134.0 Spur Ridge 2400
25
Table 2. Importance Value percentage for each species at each site with dominant species highlighted in yellow. Merck Forest: Rupert, VT.
Red Spruce-Northern Mesic Red Oak-Northern Hardwood Forest Northern Hardwood Forest Hardwood Forest Dry Oak Woodland Species site 1 site 2 site 3 site 4 site 5 site 6 site 7 site 8 site 9 site 10 site 11 site 9 site 10 site 11 Am. Basswood - - 0.01 - 0.03 - 0.01 - 0.02 0.03 - - - -
Am. Beech 0.06 0.04 0.32 0.35 0.19 0.18 0.19 0.24 0.11 0.07 0.22 - 0.04 -
black birch - - 0.01 0.02 - - - 0.02 0.03 - - - - -
black cherry - 0.04 0.05 0.06 0.02 0.07 0.01 - - - - - - 0.10
grey birch 0.14 0.13 0.01 0.03 0.03 - - 0.04 0.02 - - - 0.04 -
hop-hornbeam - 0.12 0.02 0.03 0.07 0.03 0.11 0.02 0.17 0.07 - 0.24 0.23 0.05
paper birch - - 0.01 - 0.02 - 0.01 0.02 0.02 - - - - -
pin cherry - - - - - 0.03 - 0.02 - - - - - -
quaking aspen - - - - - 0.03 - - - - - - - -
red maple 0.15 0.12 - - - - - 0.09 - - - - - -
red oak 0.04 0.04 - - 0.09 0.03 0.07 0.04 0.30 0.24 0.31 0.47 0.53 0.51
red spruce 0.44 0.24 0.04 - - 0.03 0.05 0.07 - - - - - -
shadbush - - - - - - - - - - - 0.04 - -
striped maple 0.04 0.04 0.03 0.02 0.01 0.08 0.01 - - - - - - -
sugar maple 0.06 0.17 0.33 0.35 0.48 0.42 0.51 0.22 0.19 0.47 0.45 0.15 0.12 0.34
tamrack - - - 0.01 - - - - - - - - - -
white ash - 0.06 0.02 0.02 0.05 0.03 0.02 0.06 0.14 0.12 - 0.10 0.04 -
yellow birch 0.07 - 0.15 0.11 0.01 0.07 0.01 0.16 - - 0.02 - - -
total 1 1 1 1 1 1 1 1 1 1 1 1 1 1
26
Northern Hardwood Forest Community (Sites 3-8) According to the forest management plan, the vast majority of Merck is a northern
hardwood forest (NHF) with patches of rich NHF. This held true in this project, as six out
of eleven sites were NHF (Sites 3-8). These sites were spread from east to west in the
middle portion of the property. Sites 3-8 totaled 252.7 acres ranging from 17 to 85.2acres.
The dominant tree species at Sites 3-8 were sugar maple and American beech (Fagus
grandifolia Ehrh.) (Table 2). Yellow birch (Betula alleghaniensis Britton.) had a
substantial presence in the canopy at Sites 3, 4, and 8 and hop-hornbeam at Site 7. No
signs of dry oak woodland were found at these sites.
Mesic Red Oak-Northern Hardwood Forest and Dry Oak Woodland (Sites 9-11)
Small communities of dry oak woodlands (DOW) were found at Sites 9, 10 and 11 with
mesic red oak-northern hardwood forest (MRONHF) inhabiting the rest of each site. The
boundaries of the DOW community were delineated based on the species composition
and site characteristics. These sites were located at the southern portion of the property.
The dry oak woodland at sites 9 and 10 were 1.4 acres and 0.9 acres at site 11. The
MRONHF community (excluding DOW communities) total acreage was 63 acres ranging
from 14.5 to 32.4.
The dominant tree species in the mesic red oak-northern hardwood forest was
sugar maple and red oak (Table 2). Species that were also prominent include, American
beech in Sites 9 and 11; white ash in Sites 9 and 10; and hop-hornbeam (Fraxinus
Americana L.) at Site 9. The dominant Species in the dry oak woodland community was
red oak (Table 2). Sugar maple was prominent in at all three Sites, and hop-hornbeam in
Sites 9 and 10.
27
Soils
The soil types at all the sites tend to be similar with the exception of the Pitstown loam
(48C&D and 49C&D) and Brayton loam (50B) which both have a seasonally high water
table (Map 5, Appendix A). The Brayton loam is found in depressions and drainages as
well as toe slopes of hills and ridges. It is poorly drained, moderately deep to dense basal
till, and very deep to bedrock. The slopes are gently sloping or nearly level (0-5% slope).
These soils are poorly suited for cultivated crops due to the stony surface. Most areas of
this map unit are in woodland, but some are used for unimproved pasture. The
productivity of growing sugar maple is low. Management concerns include equipment
limitations, seedling mortality, and windthrow due to the high water table. There is only
one occurrence of this soil type in the southeastern portion of Site 7.
The Pittstown loam has a slope of 8-25% and can be stony (49C&D) or have
relatively few stones (48C&D). It is moderately well drained, moderately deep to dense
basal till and very deep to bedrock. It is found on summits, shoulders, and backslopes of
knolls, hills, and ridges. These are productive sites for sugar maple and tend to be cleared
for cultivation unless they are stony. The management concerns include equipment
limitations, hazards of erosion, and windthrow due to the steep slopes and seasonally
high water table. The Pittstown loam series is found in Sites 2, 3, 5, 7, and 8 which are
all in the northern half of the property.
All the other soil types are found on the backslopes or summits of hills and
mountains or on narrow ridges. The slopes vary in steepness from 8% to 70% with the
majority in the higher range. These soil types are well-drained, acidic, stony or rocky, and
have a moderate to rapid permeability. They have a low or very low site productivity
index for sugar maple. The management concerns, especially on the steeper slopes, are
28
erosion, equipment limitations, seedling mortality, and windthrow. These soil types tend
to be in woodland with some small areas as unimproved pasture. The difference in the
soil types is the depth; the Taconic, Hogback, and Lyman series are shallow while the
Macomber, Dutchess, Rawsonville, Tunbridge, Birkshire, and Houghtonville series are
deep.
Landscape
The land formations in which the sites were located include mountaintop, ridge, spur
ridge, and one hillside slope (Table 1). The majority of the sites were on mountain ridges
including, Sites 3,4,5,7, and 11. Site 1 and 6 were mountaintops; Sites 8, 9, and 10 were
on spur ridges; and Site 2 was on the southeastern slopes of a hill. The dry oak woodlands
were found on one ridge and at two spur ridges.
The elevation of the sites ranges from 1700’ at Site 9 in the southern portion of
the property to 2600’ at the top of Mount Antone. With the exception of Site 11 the DOW
were found at a lower elevation than most of the other sites. Site 9 was at 1700’; Site 10
was at 1900’; and site 11 was at 2400’. All of the dry oak woodlands were located in the
southern portion of the property where the majority of the red oaks forests can be found.
29
Dry Oak Woodland Analysis
Vegetation
Site 9
As mentioned earlier, red oak is the dominant species in the dry oak woodland and red
oak and sugar maple are dominant in the mesic red oak-northern hardwood forest (Table
2). While the species composition is somewhat different between the two communities, it
is the tree height and spacing that makes them easy to differentiate. The dominant canopy
trees in the DOW are estimated to be 20-60 feet with the shortest trees tending to be
found in the middle of the site and on the steepest slopes. The estimated tree height in the
MRONHF is 75 feet. The greater spacing between trees in the DOW allowed more
sunlight to penetrate to the ground. While this was a qualitative observation, the lower
basal area of 120 ft2/acre in the DOW as compared to 141ft2/acre in the MRONHF
supports this notion (Table 1).
The abundance of seedling and sapling species provides a good indication of what
the canopy composition will look like in the future. The dominant seedling species in the
MRONHF of Site 9 was sugar maple; red oak and shadbush were the dominant seedling
species in the DOW (Figure 3). For saplings, American beech and striped maple (Acer
pensylvanicum L.) made up the dominant species in the MRONHF and shadbush was
dominant in the DOW (Figure 4).
30
Figure 3. Average density of seedlings per acre (± 1 Standard Error) for each species in the mesic red oak-northern hardwood forest and dry oak woodland community of Site 9. Merck Forest: Rupert, VT.
Figure 4. Average density of saplings per acre (±1 Standard Error) for each species in the mesic red oak-northern hardwood forest and dry oak woodland community of Site 9. Merck Forest: Rupert, VT.
1330 67
300
1633
1100
567
333
600
300100 133
0
1833
0
500
1000
1500
2000
2500
Den
sity
(st
ems/
acre
)
Seedling Species
dry oak woodland
mesic red oak-northern hardwood forest
0
260
920
0
700
830
533
0
400
800
1200
1600
Den
sity
(st
ems/
acre
)
Sapling Species
dry oak woodland
mesic red oak-northern hardwood forest
31
The lower synusium, which is composed of substrate and ground vegetation,
provides the detailed information to fully analyze a site. There are several important
comparisons that can be made between the vegetation and substrate in the mesic red oak-
northern hardwood forest and dry oak woodland. At Site 9, the average percent cover of
vegetation was significantly higher in the DOW (n=30) than the MRONHF (n=30) (Z= -
4.19, P=0.0001) (Figure 5). The percent cover of coarse woody debris (CWD) and bare
ground was higher in the MRONHF and there was slightly more exposed rock coverage
in the DOW. The average percent cover of grass was significantly higher in the DOW
(n=30) than the MRONHR (n=30) (Z=1.93, P=0.053).
Comparisons between the indicator and common species of a dry oak woodland
further help to characterize the difference between the communities. Lowbush blueberry
(Vaccinium angustifolium Aiton.) and shadbush were present in the DOW and not in the
MRONHF (Table 3). Goldenrod (Solidago spp. L.) and wood aster (Eurybia divaricata
Nesom.) were present in the MRONHF and not in the DOW. Red oak and sugar maple
are the only seedlings present in the DOW with red oak having a greater IV value.
32
Table 3. Mean percent cover (± 1 Standard Error) of the substrate and vegetation of the forest communities at Site 9. Merck Forest: Rupert, VT.
Site 9
Mesic Red Oak- Northern Hardwood Forest Dry Oak Woodland Type/Species Percent Cover Range Percent Cover Range Substrate forest litter 59.4 ± 5.1 2.5-97.5 59.4 ± 4.5 15-97.5 bare ground 12.7 ± 3.3 2.5-37.5 3.2 ± 1.8 2.5-37.5 CWD 14.7 ± 3.1 2.5-62.5 5.4 ± 1.2 2.5-15 rock 0.3 ± 0.1 2.5-2.5 1.8 ± 3.2 2.5-37.5 moss/lichen 0.9 ± 0.5 2.5-2.5 11.6 ± 4.3 2.5-62.5 Herbaceous Plants goldenrod 5.4 ± 0.7 2.5-15 0 wood aster 3 ± 0.2 2.5-2.5 0 Grass 19.9 ± 5.4 2.5-97.5 28.3 ± 4 2.5-62.5 Shrub lowbush blueberry 0 21.2 ± 6.2 2.5-85 shadbush 0 3 ± 1.6 2.5-37.5 Tree seedlings ash 0.5 ± 0.2 2.5-2.5 0 birch 1 ± 0.2 2.5-2.5 0 cherry 0.8 ± 0.2 2.5-2.5 0 maple 0.3 ± 0.5 2.5-2.5 1.3 ± 0.7 2.5-15 oak 0.3 ± 0.2 2.5-2.5 6.7 ± 2.7 2.5-37.5
33
Site 9
Figure 4. Mean percent cover of the substrate and vegetation of the forest communities at Site 9. Merck Forest: Rupert VT. March 2012
Site 10
The canopy composition in Site 10 was similar to that of Site 9 with red oak dominant in
the DOW and red oak and sugar maple dominant in the MRONHF (Table 2).
The estimated tree height in the DOW was 50 feet compared to 70 feet in the MRONHF.
It is less noticeable than Site 9, but there was still a slight difference in the tree spacing
and light availability between the communities. The basal area was 125ft2/acre in the
MRONHF and 115ft2/acre in the DOW (Table 1).
The dominant seedling species in Site 10 was red oak and hop-hornbeam in both the
DOW and MRONHF with red oak density greater in the DOW (Figure 6). For the
saplings, American beech and birch were dominant in the MRONHF and low densities of
shadbush, hop-hornbeam, and a few American beech in the DOW (Figure 7).
34
Figure 6. Average density of seedlings per acre (± 1 Standard Error) for each species in the mesic red oak-northern hardwood forest and dry oak woodland communities of Site 10. Merck Forest: Rupert, VT.
Figure 7. Average density of saplings per acre (± 1 Standard Error) for each species in the mesic red oak-northern hardwood forest and dry oak woodland community of Site 10. Merck Forest: Rupert, VT.
75
200225
1025
3175
125
425
300 2000
13001100
0
950
0
1000
2000
3000
4000
5000
Des
nit
y (s
tem
s/ac
re
Seedling Species
dry oak woodland
mesic red oak-northern hardwood forest
330
167 217
1467
717
17 00
400
800
1200
1600
2000
2400
Den
sity
(st
ems/
acre
Sapling Species
dry oak woodland
mesic red oak-northern hardwood forest
35
The substrate and vegetation coverage for the MRONHF and DOW at Site 10 was
close to what we would expect to see at these sites. The average vegetation cover was
higher in the DOW (n=40) than the MRONHF (n=20) (Figure 8), but was not
significantly different by a small margin (Z=1.86, P= 0.063). The average percent cover
of grass was significantly higher in the DOW (n=40) than the MRONHF (n=20)
(Z=3.666, P=0.0002). There was more forest litter in the MRONHF and more coarse
woody debris and bare ground in the DOW. There was slightly more exposed rock
present in the MRONHF.
Shadbush and lowbush blueberry are present in small amounts in the DOW and
not the MRONHF (Table 4). A few false Solomon’s Seal (Smilacina racemosa Link.)
and wood aster are present in both natural communities. The tree seedling species
diversity was greater at Site 10 than Site 9 with red oak having the greatest IV value.
36
Table 4. Mean percent cover (± 1 Standard Error) of the substrate and vegetation of the forest communities at Site 10. Merck Forest: Rupert, VT.
Site 10
Mesic Red Oak- Northern Hardwood Forest Dry Oak Woodland Type/Species Percent Cover Range Percent Cover Range Substrate forest litter 78.5 ± 4.6 62.5-97.5 42.4 ± 4.4 2.5-97.5 bare ground 8.7 ± 2.6 2.5-37.5 12.7 ± 2.7 2.5-62.5 CWD 6.1 ± 2.2 2.5-15 13.2 ± 2.4 2.5-62.5 rock 6.2 ± 3.2 2.5-62.5 4.8 ± 1.5 2.5-37.5 moss/lichen 5.1 ± 2.1 2.5-37.5 7.3 ± 2.3 2.5-62.5 Herbaceous Plants Soloman’s seal 0.2 ± 0.2 2.5-2.5 0.4 ± .2 2.5-2.5 wood aster 1.6 ± .7 2.5-15 0.2 ± .1 2.5-2.5 Grass 10 ± 2.5 2.5-37.5 35.4 ± 4.2 2.5-97.5 Shrub lowbush blueberry 0 0.4 ± .4 15-15 shadbush 0 0.1 ± 0.1 2.5-2.5 Tree seedlings Am. beech 0.4 ± 0.2 2.5-2.5 0.5 ± 0.2 2.5-2.5 ash 0.5 ± 0.2 2.5-2.5 0.2 ± .1 2.5-2.5 cherry 0 0.5 ± 0.2 2.5-2.5 hop-hornbeam 3.1 ± 1.2 2.5-15 2.6 ± 0.7 2.5-15 maple 3.6 ± 1.3 2.5-15 0.7 ± 0.2 2.5-2.5 oak 9.9 ± 3.5 2.5-62.5 8.1 ±m1.8 2.5-37.5
37
Site 10
Figure 8. Mean percent cover of the substrate and vegetation of the forest communities at Site 10. Merck Forest: Rupert VT.
Site 11 Site 11 had a similar canopy composition to the previous Sites with red oak dominant in
the DOW and red oak and sugar maple dominant in the MRONHF (Table 2). The
estimated tree height was 50 feet in the DOW and 65 feet in the MRONHF. The overall
basal area was lower in the MRONHF at 123.1ft2/acre compared to 134ft2/acre in the
DOW (Table 1). However, the DOW still felt more open and sunny due to the fact that
the MRONHF had numerous American beech saplings.
American beech was the dominant seedling species in the MRONHF of Site 11
where as, sugar maple, red oak, and cherry, were the dominant species in the DOW
(Figure 9). In the MRONHF, American beech was the dominant sapling species
compared to hop-hornbeam in the DOW (Figure 10).
38
Figure 9. Average density of seedlings per acre (± 1 Standard Error) for each species in the mesic red oak-northern hardwood forest and dry oak woodland community of Site 11. Merck Forest: Rupert, VT.
Figure 10. Average density of saplings per acre (± 1 Standard Error) for each species in the mesic red oak-northern hardwood forest and dry oak woodland community of Site 11. Merck Forest: Rupert, VT.
0
100
800 950
200
1300
467
0 0 0 33
133
0
500
1000
1500D
esn
ity
(ste
ms/
acre
)
Seedling Species
dry oak woodland
mesic red oak-northern hardwood forest
40 80
2660
00
500
1000
1500
2000
2500
3000
3500
Den
sity
(st
ems/
acre
)
Sapling Species
dry oak woodland
mesic red oak-northern hardwood forest
39
The substrate and vegetation coverage for the DOW at Site 11 was close to what
we would expect at this site. The average percent cover of vegetation was significantly
higher in the dry oak woodland (n=40) than the mesic red oak-northern hardwood forest
(n=30) (Figure 11) (Z=6.673, P=0.0001). The average percent cover of grass was
significantly higher in the DOW than the MRONHF (Z=3.666, P=0.0002). There is a
higher average percent of forest litter in the MRONHF and more coarse woody debris,
and rock in the DOW. The average percent of bare ground is slightly higher in the
MRONHF.
There is blueberry present in the DOW and none in the MRONHF (Table 5).
There are more herbaceous species in the DOW with the highest amount of wood fern
(Dryopteris spp. Adans.) followed by goldenrod. Blackberry (Rubis allegheniensis
Porter.) and bindweed (Polygonum convolvulus Court.) are present in the DOW. There is
a diversity of seedling species in the DOW.
40
Table 5. Mean percent cover (± 1 Standard Error) of the substrate and vegetation of the forest communities at Site 11. Merck Forest: Rupert, VT.
Site 11
Mesic Red Oak- Northern Hardwood Forest Dry Oak Woodland Type/Species Percent Cover Range Percent Cover Range Substrate forest litter 91.7 ± 2.1 37.5-97.5 47.6 ± 5.7 2.5-97.5 bare ground 2.7 ± 2.1 2.5-15 1.2 ± 0.6 2.5-15 CWD 5.7 ± 1.5 2.5-15 11.4 ± 2.5 2.5-62.5 rock 2.7 ± 2.1 2.5-62.5 8.5 ± 3.4 2.5-97.5 moss/lichen 2.7 ± 2.1 2.5-62.5 5.5 ± 2.4 2.5-62.5 Herbaceous Plants Canada mayflower 0 0.2 ± 0.1 2.5-15 goldenrod 0 2.9 ± 1 2.5-15 wild mint 0 1.2 ± 0.5 2.5-15 wood fern 2.3 ± 0.9 2.5-15 4.4 ± 1.7 2.5-37.5 Grass 5.7 ± 2.1 2.5-37.5 34.1 ± 5.6 2.5-97.5 Shrub lowbush blueberry 0 3.9 ± 2.1 2.5-62.5 blackberry 0.1 ± 0.2 2.5-2.5 5.1 ± 1.7 2.5-37.5 Tree seedlings Am. beech 0.5 ± 0.2 2.5 0 cherry 0 1.7 ±1.1 2.5-37.5 hop-hornbeam 0 7 ± 0.4 2.5-15 maple 0.25 ± 0.1 2.5-2.5 2.7 ± 0.7 2.5-15 oak 0 2 ± 0.6 2.5-15 Vine bindweed 0 3.9 ± 1.4 2.5-37.5
41
Site 11
Figure 11. Mean percent cover of the substrate and vegetation of the forest communities at Site 11. Merck Forest: Rupert VT.
Soils (MRONHF vs. DOW) As mentioned earlier, the soils in Sites 9-11 were similar to those found at the other sites
with the exception that none of the soils with a higher water table such as the Pittstown
loam (48C&D and 49C&D) or Brayton (50B) loam were present at these sites (Map 4).
The differences between the soils found in the DOW and MRONHF communities were
very slight and several of the soil types overlap (43E, 42C, 109E, and 112D).
In general, the soils supporting the DOW tended to be strongly sloping, very
rocky, excessively drained, extremely acid, and have moderate to severe management
concerns in regards to erosion hazards, equipment limitations, seedling mortality, and
windthrow (Appendix A). The soil types in the DOW included: Taconic-Macomber
Complex with 25-60% slopes (43E) in Sites 9 and 10; a small amount of Macomber-
Taconic Complex 8-15% slopes (42C) in Site 10; Turnbridge Birkshire Complex with 15-
42
25% slopes (109E) and Rawsonville-Hogback Complex with 15-25% in Site 11. The
soils of the MRONHF tended to be somewhat less harsh with moderately steep slopes,
deep well drained soils, and overall less severe management concerns. The soils in the
MRONHF that were not in the DOW include Dutchess Channery loam with 15-60%
slopes at all three sites, and Turnbridge Lyman with 15-25% slopes at Site 11.
On average the soil in the MRONHF was 6.6cm deeper than the soil in the DOW
(Table 6). The soil depth in the dry oak woodland (n=30) was significantly deeper than
that of the mesic red oak-northern hardwood forest (n=30) in Sites 9 (Z=2.869, P= 0.004)
and 11 (Z=3.986, P= 0.0001). There was no significant difference in soil depth at Site 10
(Z=1.739, P= 0.082). The range starts at zero in the DOW in all three sites indicating that
at some of the sample points there was rock and no soil. The range was much larger in
the MRONHF with the higher end of the range being much greater than that of the DOW.
Table 6. Average soil depth in centimeter (± 1 Standard Error) in the DOW and MRONHF communities of Sites 9-11. Mesic Red Oak- Site Northern Hardwood Forest Range Dry Oak Woodland Range 9 18.9 ± 1.9 5.5-45.0 11.4 ± 1.4 0-19.0 10 11.4 ± 1.4 2.0-38.0 7.1 ± 0.9 0-18.5 11 15.1 ± 1.5 3.0-25.5 7.1 ± 1.1 0-21.5 9-11 15.1 ± 1.7 2.0-45.0 8.5 ± 1.2 0-21.5
43
Landscape (DOW 9-11) The dry oak woodland communities were all found on sites in the southern portion of
Merck’s boundary. The DOW in Sites 9 and 10 was located on spur slopes facing directly
south with southeasterly and southwesterly exposure on either side. DOW 9 and 10 are in
close proximity and separated by a patch of forest where a seed tree harvest took place in
2007 in hopes of regenerating oak. DOW 11 is different from 9 and 10 in that it is
located on a narrow ridge with a southeastern aspect. At the top edge of the ridge and the
northwestern boundary of DOW 11 are Masters Mountain Trail and the edge of the
property. Plant species uncharacteristic to dry oak woodland such as bindweed,
goldenrod, and blackberry were growing rampantly along the trail and appeared to be
spreading into the DOW. There is also a trail going through DOW 9, but the impacts
appear to be less severe.
Ecological Integrity
Dry Oak Woodland 9
Based on appearance DOW 9 is by far the most ecologically intact out of the three sites.
Grass species and blueberry are abundant in the understory, shadbush is present in the
midstory, and oaks make up the canopy. The dry oak woodland community description of
the short, gnarled, trees spaced at a distance is exactly what it looks like in Site 9. There
is a healthy population of oak seedlings, but they are not being recruited into the sapling
stage. Many of the seedling are what is known as “flat top oaks” meaning that they are
small like a normal oak seedling, but have larger leaves, more extensive root system, and
are several years old. They are waiting until the required resources, such as light and
44
sometimes water, are available so that they can grow quickly up into the canopy (Van
Lear and Watt 1992).
While the appearance of the dry oak woodland at site 9 looked like an exemplary
community type, the sugar maples encroaching upon the canopy and the surprisingly high
level of forest litter in the understory are concerning. The increase in sugar maples and
forest littler may lead to a change in species composition and degradation of the dry oak
woodland community. Another factor that could harm the ecological integrity of the site
is the trail that runs through the middle of the community. The trail can be a vector for
unwanted species, and trampling of sensitive vegetation or coarse woody debris can alter
the site.
Dry Oak Woodland 10
Despite many similarities in the landscape, DOW 10 does not have the same ecological
integrity as DOW 9. It is not as easily recognizable as a dry oak woodland because the
trees are much taller and straighter and less light penetrates the forest floor. There was
only a very small patch of lowbush bluberry. The dense populations of beech and birch
saplings that are starting to come into the DOW community is of great concern. Similar
to site 9, sugar maple is becoming a large component of the canopy and will start to
dominate if new oaks are not recruited.
While DOW 10 did not have the same canopy characteristics as site 9 there were
some aspect of the site that contributes to its ecological integrity. The oak seedling
population is greater at site 10 than at 9. There is also more coarse woody debris, exposed
rock, and bare ground typical of dry oak woodlands. While there is a trail and cabin for
45
visitor use nearby, there is probably less human disturbance to the community than the
other DOW’s.
Dry Oak Woodland 11
Dry oak woodland 11 is also not as ecologically intact as DOW 9. The trees are
somewhat short and gnarled, but the small, narrow size of the community is a concern.
Dow 10 is surrounded by a thick beech scrub forest in addition to the hiking trail. Sugar
maple seedlings are more abundant than oak seedlings and cherry saplings can be seen
growing in the middle of the community. Other species appear to be coming in from the
hiking trail such as bindweed, blackberry, and goldenrod. There is more lowbush
blueberry than at DOW 10, but much less than DOW 9. Without restoration it appears
that this dry oak woodland community will not persist.
46
Specific Management Recommendations
There are a number of possible restoration treatments that can be applied to the dry oak
woodlands at Merck, which have been discussed in the introduction of this report. While
it may be feasible to conduct most of these treatments to each site, priority should be
given to those sites with the greatest ecological integrity. It is important to prioritize the
sites in order to have a greater success rate. Treatments may also be restricted or not
feasible due to site conditions or limited time and resources.
Fire is likely the best management technique for accomplishing the desired results
at each of the dry oak woodlands communities at Merck. Most resource professionals
find prescribed burns to be the best way to regenerate oak and recruit it into the canopy
(Brose et al. 2008, Loftis and McGee 1993, Abrams 1992, Lorimor 1992, Smith 1992).
Fire would also remove some of the sugar maples to open up the canopy and promote an
understory dominated by grasses and blueberry. Slash and other fuel accumulation should
be removed from the base of the residual oak trees to prevent fire damage.
A fire regime with a high frequency should be set in place until the sites
composition is restored. Due to the difficulties in doing a prescribed burn in New
England a burn every 5 years would be a reasonable goal. The dry oak woodland should
be monitored after the fire treatment in order to track accomplishments and make
informed decisions for future management strategies. Mechanical cutting can be used in
conjunction with a burn to eliminate the undesirable species that may be too large to be
killed in a fire or to help maintain the site until it is possible to burn. The application of
herbicide can be used on species that sprout back or spread quickly. Planting can be done
to build up a seed bank to promote the dry oak woodland vegetation in places where grass
or blueberry maybe lacking.
47
Deer browse does not appear to be a significant issue in Merck’s dry oak
woodlands but may be a stressor thereby decreasing the ecological integrity of these sites.
Hunting is popular on the Merck property and should be maintained to help keep large
deer populations from harming the dry oak woodland vegetation. Leaving slash behind
after a harvest would also help prevent the deer from entering the dry oak woodlands.
Fencing is not advisable due to the cost and energy it would require to maintain. It is
important that when monitoring the dry oak woodlands in the future the deer browse
intensity is incorporated so that more extreme measures of controlling deer can be taken
if need be.
There is the potential to involve researchers, educators, and the general public to
follow the restoration of Merck’s DOW’s from start to finish. While some of these
management options may require substantial funds, eliciting public interest should be
easy and may help to offset the cost. In the very least, before and after photos should be
taken of restoration efforts.
Dry Oak Woodland 9
The dry oak woodland at Site 9 is 1.4 acres in size and with less restoration effort
than the other sites, it has the potential be a conservation success story and a major asset
to Merck. The ecological integrity is relatively intact in DOW 9, and therefore it should
be given preference over the other sites. Plans to do a prescribed burn in the spring in the
near future (within the next 5 years) depending on weather (Map 5). After the burn it may
be advisable to mechanically remove some of the undesirable tree species that may have
grown too large to be killed by fire. Planting is probably not necessary since there is
already a high enough coverage of dry oak woodland vegetation present; however there is
48
the opportunity to introduce white oak or chestnut oak. The introduction of additional oak
species would improve the wildlife potential and the overall diversity and integrity of the
site.
In the case that this site is not burned this year or in the next few years dry oak
woodland 9 can probably be left alone for several years and there would be no major
changes to the composition. However, it may be beneficial to cut down some of the
undesirable trees and saplings to bring additional sunlight to the understory vegetation. A
small crew could accomplish this in few hours since the site is small and only a few trees
would need to be felled. Herbicide would not be necessary at this site since there does not
appear to be a significant presence of weeds or re-sprouting trees. The trail that runs
through the DOW community does not appear to be a major disturbance but efforts to
monitor visitor impacts to the site should be taken into consideration.
Dry Oak Woodland 10
Dry oak woodland 10 is 1.4 acres in size and less ecologically intact than Site 9
and therefore it should be less of a priority and will require more effort. A prescribed
burn may be feasible at this site, but extra caution will need to be taken to keep the fire
away from Nenorod Cabin, which is in close proximity. Restricting additional structures
from being built near this site will help insure the opportunity of restoring this site with a
prescribed burn.
While fire is probably the best technique to restore this dry oak woodland and
may even be required for the continuation of its existence, in the short-term, mechanical
removal of the non-oak canopy and sapling species will help to maintain the site. The
beech whips can be controlled with herbicide or repetitive cutting. The DOW vegetation
49
may also benefit from a 50-foot buffer of saplings cut in the adjacent mesic red oak-
northern hardwood forest. Removing the saplings will be more successful if done in a
five-year interval. Monitoring the site after each treatment will be important so that
management strategies can be adjusted as needed. Planting lowbush blueberry after the
canopy and midstory has been opened up could speed up the process of increasing its
coverage in the understory and thereby improving the integrity of the site.
Dry Oak Woodland 11 Dry oak woodland at site 11 is the smallest in size at 0.9 acres and will take a
substantially greater effort to reach the same level of ecological integrity as Site 9. The
shape of the community is also long and narrow, which further decreases its integrity by
having so much edge habitat and little to no core habitat. Therefore treating a large buffer
zone of 100 ft in the mesic red oak northern hardwood forest would create the potential to
expand the size of the dry oak woodland. In addition to treating the undesirable species it
is advisable to re-route Master’s Mountain Trail, as it appears to be a vector for weeds
and potential invasive plants to become established.
The low seedling density for red oak and higher density for sugar maple indicates
that DOW 11 would benefit from a burn or regeneration cut. A prescribed burn would be
the best way to prepare the site for oak seeds to germinate and grow. If fire is a possible
treatment either now or in the future it is important that no structures are built in the
vicinity. The northwestern edge of DOW 11 is right on the property line, but with
communication with the adjacent landowner and a substantial fire line it would be
feasible to burn.
50
If fire is not a possible prescription for site 11 than a regeneration cut with
scarification of the soil will improve the chances of red oak becoming established on this
site. However scarification of the soil is difficult without the use of heavy equipment,
which may be limited by the steep slopes there. It will take a fair amount of effort to
restore DOW 11 and the question of whether fire is required to maintain this community
type is important to the course of actions taken.
51
Conclusion Out of the three dry oak woodlands communities found at Merck Forest only one of them
had its ecological integrity relatively intact. To make the best use of resources and time,
efforts should be targeted to the healthiest dry oak woodland to maintain and enhance its
structure and composition. Fire appears to be the most suitable restoration method but
may be supplemented with mechanical cutting or herbicide. Additional research on
whether fire is vital to the persistence of dry oak woodland communities in New England
and what fire regime would be the best are important topics that will increase our
understanding of these communities. Management decisions and sustainable practices
should be implemented with care to protect these important natural resources in order to
add to the biodiversity of the region and the future health of the forest ecosystem.
52
Map 1. Location of Merck Forest in context of the state of Vermont and the town of Rupert.
53
Map 2. Trail map for Merck Forest and Farmland Center in Rupert Vermont.
54
Map 3. Dry oak woodland potential sites based on topography and southern aspect.
55
Map 4. Sampling method depicting points and transects at each of the eleven sites and three oak woodland communities.
56
Map 5. Soil types at each of the eleven potential sites at Merck Forest. Data taken from Natural Resource Conservation Service (NRCS) soil survey.
57
Map 6. Location of future controlled burn.
58
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62
Appendix A. Soils associated with the oak woodland potential sites at Merck Forest.
Soil Code
Soil Name Slope Management Concerns Productivity Erosion Hazard1
Wind Throw2
Species Site Index3
42C Macomber-Taconic Complex
8-15% rocky
Slight Slight/Sev Paper birch Sugar maple Red oak
53-60 50-65 50-70
42D Macomber-Taconic Complex
15-25% rocky
Moderate Slight/Sev Sugar maple Paper birch Red oak
50-65 53-60 50-70
42E Macomber-Taconic Complex
15-25% rocky
Moderate Slight/Sev Sugar maple Paper birch Red oak
50-65 53-60 50-70
43E Taconic Macomber Complex
25-60% very rocky
Severe Mod/Sev Red oak Paper birch Sugar maple
50-70 53-60 50-65
47D Duchess channery loam
15-25% very stony
Moderate Slight White pine Red oak Sugar maple
66 62 60
47E Duchess Channery loam
25-60% very stony
Severe Slight White pine Red oak Sugar maple
66 62 60
48C Pittstown loam 8-15% Slight Moderate White pine Sugar maple Red oak
80 66 72
48D Pittstown loam 15-25% Moderate Moderate White pine Sugar maple Red oak
80 66 72
49C Pittstown loam 8-15% very stony
Slight Moderate White pine Sugar maple Red oak
80 66 72
49D Pittstown loam 15-25% very stony
Moderate Moderate White pine Sugar maple Red oak
80 66 72
50B Brayton loam 0-5%
Slight Severe Paper birch White pine Red maple
60 67 65
96F
Hogback-Rawsonville-rock outcrop complex
25-70% very stony
Severe Severe Sugar maple Red oak White pine
50 63 55
109C
Tunbridge-Birkshire Complex
8-15% rocky
Slight Slight/Mod White pine White ash Sugar maple
50-72 62-65 52-60
109D Tunbridge-Birkshire Complex
15-25% rocky
Moderate Slight/Mod White pine White ash Sugar maple
50-72 62-65 52-60
63
Continuation of Appendix A.
1Erosion Hazard – the probability that erosion can occur as a result of site preparation or cutting. Slight – no particular measures need to be taken to prevent erosion under normal conditions Moderate – erosion control measures are needed for silviculture activities Severe – special precautions are necessary to control erosion in most silviculture activities
2Wind Throw – the likelihood that trees will be uprooted by the wind Slight – no trees are normally uprooted by the wind Moderate – moderate or strong winds occasionally uproot trees when soil is wet Severe – moderate or strong winds may blow down many trees when soil is wet
3Site Index – average height in feet that a dominant or codominant tree can reach in a specified number of years. Source: United States Department of Agriculture. 1998. Soil Survey of Rutland County Vermont.
National Cooperative Soil Survey (United States Department of Agriculture Soil Conservation Service and Vermont Agricultural Experiment Station).
109E
Tunbridge-Birkshire Complex
25-50% rocky
Severe Slight/Mod White pine White ash Sugar maple
50-72 62-65 52-60
111E
Rawsonville-Houghtonville Complex
25-60% rocky
Severe Slight/Mod White ash Am. beech Sugar maple
65-67 64-65 60
112D
Rawsonville-Hogback Complex
15-25% very rocky
Severe Mod/Sev Am. Beech Red spruce Sugar Maple
64 42-45 50-60
112E
Rawsonville-Hogback Complex
25-60% Very rocky
Severe Mod/Sev Am. Beech Red spruce Sugar Maple
64 42-45 50-60
116F
Lyman-Tunbridge-Rock outcrop Complex
25-70 very stony
Severe Mod/Sev Red spruce White spruce Sugar maple
40-50 55 50-60
118D
Tunbridge-Lyman Complex
15-25% very rocky
Moderate Mod/Sev Red spruce White spruce Sugar maple
40-50 55 50-60
118E
Tunbridge-Lyman Complex
25-60% very rocky
Severe Mod/Sev Red spruce White spruce Sugar maple
40-50 55 50-60
64
Appendix B. Species list of all plants found at the potential sites at Merck Forest, East Rupert VT. March 2012 Common name Scientific name Family Habitat preference Angiosperm Trees red maple Acer rubrum Aceraceae generalist sugar maple Acer saccharum Aceraceae ecoindicator: mesic uplands black birch Betula lenta Betulaceae generalist paper birch Betula papyrifera Betulaceae generalist grey birch Betula populifolia Betulaceae generalist yellow birch Betula alleghaniensis Betulaceae moist well drained sites hop-hornbeam Ostrya virginiana Betulaceae ecoindicator: rich, dry woods American beech Fagus grandifolia Fagaceae generalist red oak Quercus rubra Fagaceae dry warm sites white ash Fraxinus Americana Oleacea ecoindicator: moist uplands pin cherry Prunus pensylvanica Rosaceae areas with fire history black cherry Prunus serotina Rosaceae areas with fire history bigtooth aspen Populua grandidentata Salicaceae dry or moist soils quaking aspen Populus tremiloides Salicaceae generalist Am. basswood Tilia Americana Tiliaceae ecoindicator: rich moist forests Gymnosperm trees red spruce Picea rubens Pinaceae ecoindicator: acidic, cool, moist sites Tamarack Larix laricina Pinaceae planted Shrubs and Vines striped maple Acer pensylvanicum Aceraceae generalis lowbush blueberry Vaccinium angustifolium Ericaceae ecoindicator: dry acidic sites black bindweed Polygonum convolvulus Polygonaceae disturbed areas shadbush Amelanchier Rosaceae generalist blackberry Rubis alleghenniensis Rosaceae disturbed areas Herbaceous goldenrod Solidago spp. Asteraceae generalist wood aster Eurybia divaricatus Asteraceae woods wood fern Dryopteris spp. Dryopteridaceae woods false Sol. Seal Smilacina racemosa Liliaceae woods Canada mayflower Maianthemum canadensis Liliaceae woods wild mint Mentha arvensis Lamiaceae moist sites
Department of Environmental Studies
MASTERS PROJECT COMMITTEE PAGE
The undersigned have examined the project entitled: Rapid Assessment of Dry Oak Woodland Natural Communities at Merck Forest in Rupert, VT presented by Heather O’Wril candidate for the degree of Master of Science and hereby certify that it is accepted*. Committee chair name Peter Palmiotto, DF Core Faculty and Director of Conservation Biology, Department of Environment Studies Date Approved by all committee members: Date Submitted to the Registrar’s Office: *Signatures are on file with the Registrar’s Office at Antioch University New England.