beaver dam sanctuary master plan

55
A Master Plan for the Beaver Dam Sanctuary Katonah, New York Elizabeth Hammen / Pamela Hurtado CONWAY SCHOOL OF LANDSCAPE DESIGN / SPRING 2008 Stewardship Across Boundaries

Upload: raul-munoz

Post on 16-Mar-2016

258 views

Category:

Documents


3 download

DESCRIPTION

Beaver Dam Sanctuary Master Plan

TRANSCRIPT

Page 1: Beaver Dam Sanctuary Master Plan

Beaver Dam Sanctuary - Master Plan

A Master Plan for the Beaver Dam SanctuaryKatonah, New York

Elizabeth Hammen / Pamela Hurtado

CONWAY SCHOOL OF LANDSCAPE DESIGN / SPRING 2008

Stewardship Across Boundaries

Page 2: Beaver Dam Sanctuary Master Plan

Acknowledgments

We wish to express our gratitude to those who assisted in the creation of this master plan including the Beaver Dam Sanctuary Steering Committee; faculty and guest instructors at the Conway School of Landscape Design; and our classmates, whose feedback and creative ideas have been invaluable. We are also grateful for the editing by Kate Kerivan and Janet Hammen.

Some data for the plan was collected from two reports: The Beaver Dam Sanctuary Natural Resource Management Plan by Beth Herr (2003) and the Forest Stewardship Plan prepared by David Berrs of Connwood Foresters, Inc. (2005).

The Conway School of Landscape Design is the only accredited institution of its kind in North America with a focus on sustainable landscape planning and design. Each year, through the ten-month masters program, eighteen to nineteen graduate students from diverse backgrounds are immersed in a range of applied landscape studies, varying in scale from residences to regions. Graduates go on to play significant professional roles in various aspects of landscape planning and design with an eye to sustainability.

The class of 2008: Kevin Adams, Sarah Bray, Jesse Froehlich, Douglas Guey-Lee, Elizabeth Hammen, Pamela Hurtado, Liz Kushner, Adrian Laine, Michael Lance, Amy Livingston, Kathleen McCormick, Katja Patchowsky, Seth Pearsoll, Catherine Pedemonti, Theresa Sprague, Thomas Sullivan, Dillon Sussman, Joseph Weidle, and Andrew Weir.

Page 3: Beaver Dam Sanctuary Master Plan

Beaver Dam Sanctuary - Master Plan

INTRODUCTIONExecutive Summary...................................................................1BDS History and Mission Statement..........................................2Master Plan Goals and Program................................................3 Existing Conditions.....................................................................4

SECTION I CONTEXTRegional ....................................................................................9Watershed................................................................................10Natural Areas and Connectivity.................................................11

SECTION II ANALYSESHabitat......................................................................................14Hydrology.................................................................................15Forest Communities................................................................ 16Soils.........................................................................................18Slopes & Drainage...................................................................19Trails.........................................................................................21

SECTION III MANAGEMENT PLANProposed Plan...........................................................................25Trails..........................................................................................26Stormwater................................................................................34Meadows...................................................................................37Forest........................................................................................38Wildlife.......................................................................................40

APPENDIXReferences................................................................................45

Page 4: Beaver Dam Sanctuary Master Plan

Section I Context

Page 5: Beaver Dam Sanctuary Master Plan

1Beaver Dam Sanctuary - Master Plan

The Beaver Dam Sanctuary Board of Directors hired the Conway School of Landscape Design team to

develop a master plan that will promote preservation of the Sanctuary while minimizing the ecological impacts of recreation. The plan proposes a trail management plan, gives recommendations for controlling stormwater, erosion and invasive species, and presents a plan for the reestablishment of the understory vegetation. Deer overgrazing and invasive vegetation are problems affecting the region, therefore bioregional planning and collaboration are recommended in order to manage the meadows and forest ecosystems of the Sanctuary.

Beaver Dam Sanctuary is located near the village of Katonah, New York, in the town of Bedford, which is located 50 miles north of New York City in north-centralWestchester County. The property abuts Interstate 684 and is surrounded by suburban houses with minimum lot sizes of five acres and properties owned by the New York City Department of Environmental Protection and the Town of Bedford. The 171-acre site is open year-round to hikers, equestrians, fly fishers and cross-country skiers. The trails within the Sanctuary make up a small part of an extensive equestrian trail network that crosses public and private lands throughout Bedford. The entire trail system, including the trails in the BDS, is maintained by a private local organization called the Bedford Riding Lanes Association.

The Beaver Dam Road divides the Sanctuary into northern and southern halves with the western edge of the southern half defined by the Beaver Dam River. As the river flows north, it meets Broad Brook in the northern half of the Sanctuary before exiting to the west and joining the Muscoot Reservoir in Katonah. The Muscoot Reservoir feeds into the Croton Reservoir, which provides ten percent of the total municipal water supply for New York City.

Several large open fields contain horse jumps and are maintained by annual mowing. Most of the BDS has 80-90 percent canopy cover, with trees including beech, maple, oak, elm, ash, sycamore, hickory, and hemlock. Deer have browsed the native shrubs extensively, so there is a noticeable absence of forest understory.

The goals of the master plan and the vision of the Sanctuary are much larger than the 171 acres. There are regional concerns that cannot be solved by the Sanctuary alone. However, with the implementation of the master plan, the Beaver Dam Sanctuary can become a model for the integration of ecological health and recreation. Because of the diversity of users of the site, this model of environmental stewardship can greatly affect the larger community and allow for collaboration with surrounding open space and conservation areas, and thus contribute to the health of the Sanctuary.

Trails

Meadows

Forests

Invasive vegetation

Beaver Dam Road

Water quality

Executive Summary

0 500 1,000250Feet¯

inspect annually and maintain

dead end = remove

entrenched = repair and maintain

harden and close in spring

harden trail in wet areas

hydric = repair and maintain

redundant = remove

BRLA trails

Highways

Major Roads

Residental Streets

BDS boundry

water

private property in BDS

surrounding parcels

TRAIL RECOMMENDATIONS (DRAFT)

Page 6: Beaver Dam Sanctuary Master Plan

Section 2 Introduction

BDS History & Mission Statement

Stone walls that marked the boundaries of former fields and pastures are a common feature in the Beaver Dam Sanctuary. Most of these were constructed in the early 1800s

to contain sheep. According to local legend, the sheep were herded through the confluence of Broad Brook and the Beaver Dam River to clean the wool before shearing. Like the stone walls, the name of this confluence, the Sheep Dip, also represents the area’s past. In 1969, several Bedford residents purchased 14 acres surrounding the Sheep Dip and formed the non-profit Beaver Dam Sanctuary. The founding members wished to preserve the cultural and natural history of the area and make it available to Bedford residents for horseback riding, walking, and fishing the streams. This area eventually grew to become became the Sanctuary that exists today.

Mission Statement of the Beaver Dam Sanctuary

The Sanctuary is managed by the Board of Trustees for the conservation of its diverse native wildlife and their habitats, and protection of the Sanctuary’s natural beauty and peaceful surroundings in perpetuity for the quiet contemplation and appreciation of nature, allowing for activities such as hiking, horseback riding, birdwatching, cross-country skiing and fishing, and for scientific and educational purposes, including ecological research and environmental studies.

Recreation in the Sanctuary is primarily for passive activities, such as jogging, hiking, horseback riding, nature appreciation, and wildlife watching.

Page 7: Beaver Dam Sanctuary Master Plan

3Beaver Dam Sanctuary - Master Plan

Master Plan Program

Assess:The existing conditions of the trail system, including river crossings• Erosion issues throughout the Sanctuary and along the Beaver Dam Road• Damage caused by the deer population and invasive vegetation•

Propose:A trail maintenance plan, with phase suggestions• A stormwater management plan to enhance the natural hydrological system• An understory restoration plan to control invasive plants and deer overbrowsing.•

Master Plan Goals & Program

This Beaver Dam Sanctuary master plan provides management guidelines and recommendations that will help integrate the two main

goals: to preserve the ecological integrity of the Sanctuary and to provide for passive recreational opportunities. Deer overgrazing and invasive vegetation are aspects of a larger problem affecting the broader area, therefore bioregional (naturally-defined regional areas) planning and collaboration are recommended in order to effectively improve the diversity and habitats of the Sanctuary.

• Preserve the ecological integrity of the Sanctuary

• Provide recreational opportunities

Beaver Dam SanctuaryMaster Plan Goals

Healthy ForestEcosystem

Human Use

Environmental Stewardship

Page 8: Beaver Dam Sanctuary Master Plan

Section 4 Introduction

Existing Conditions

While walking along the trails on the Beaver Dam Sanctuary, it is hard to imagine the hustle and bustle of New York City,

just an hour away. The densely forested hillsides screen the surrounding houses from view and make noises from the interstate barely audible. Once on the trails along the Beaver Dam River, the interstate becomes an afterthought, as the sights and sounds of the forest engulf you.

The 171-acre Sanctuary is bisected east to west by the Beaver Dam Road. The Beaver Dam Road is a gravel road that connects Katonah to Route 22 and the surrounding houses and farms. The main trail access points to the Sanctuary are from Jay Street (Route 22) to the Simpson Meadow in the north and four entrances along Beaver Dam Road, the most westerly of which provides a small amount of parking. Cross-country jumps ranging from small logs to stone walls are found along the trails of the forest and in the meadows. The trails are open to equestrians and hikers; recreational motorized vehicles and bicycles are not permitted.

The combination of overbrowsing by deer and invasive exotic plants has led to impenetrable thickets of Japanese barberry. Invasive species affect the integrity of the native forests by inhibiting forest regeneration and understory development. Oriental bittersweet is another common invasive plant in the Sanctuary. This vine can choke young saplings or overwhelm regenerating areas before tree seedlings have a chance to mature. Japanese honeysuckle, multiflora rose, garlic mustard, winged euonymus, and autumn olive are other examples of invasive exotics found in the forests and fields of the Sanctuary.

The western side of the property that abuts Interstate 684 is lined with eight-foot-high deer fencing to keep the deer from entering the highway. Deer fencing is also used along the property lines of many of the houses surrounding the Sanctuary. From the air, the Beaver Dam Road is just visible slicing through the forest and

passing two fields before going under I-684. This photo is facing north.

The forest canopy is 80-90%, allowing dappled light to reach the understory and trail users below.

Page 9: Beaver Dam Sanctuary Master Plan

5Beaver Dam Sanctuary - Master Plan

Existing Conditions

Simpson Meadow

Sheep Dip

Doc’s Pond

Access from Beaver Dam Road

NYC DEP

Page 10: Beaver Dam Sanctuary Master Plan
Page 11: Beaver Dam Sanctuary Master Plan

Beaver Dam Sanctuary - Master Plan

SECTION I CONTEXT

Page 12: Beaver Dam Sanctuary Master Plan

Section 8 I Context

Page 13: Beaver Dam Sanctuary Master Plan

9Beaver Dam Sanctuary - Master PlanI Context

The Beaver Dam Sanctuary is located in northern Westchester County, in the village of Katonah, which is in the central part of the Town of Bedford. Katonah is about an hour north of New York City.

The western side of the property abuts Interstate 684, New York City Department of Environmental Protection property and Town of Bedford lands. The north, east, and south sides of the Sanctuary are surrounded by wooded residential properties with a minimum lot size of five acres. One residence exists within the boundary of the Sanctuary, which has an easement on the driveway that is one-third mile long.

To the east of the sanctuary along Jay Road (Route 22) are the John Jay Homestead and the Harvey Boarding School. To the west, just across the interstate, is the Taconic Correctional Facility and the Bedford Hills Correctional Facility for women. A 17-acre dog park, Beaver Dam Road Park is located to the south of Beaver Dam Road, and to the west of the Beaver Dam River.

Context: Regional

Town of Bedford in Westchester County

Beaver Dam River

Page 14: Beaver Dam Sanctuary Master Plan

Section 10

I Context

Beaver Dam Sanctuary is located in the Croton Watershed, a supplier to the New York City municipal water system. The Croton Watershed covers half of Putnam and Westchester Counties and includes the entire Town of Bedford.

About ten percent of the New York City public water comes from the Croton Watershed. The remainder comes from the Delaware and Catskill Watersheds further to the north. The New York DEP protects the lands surrounding the reservoirs within these watersheds and provides funding to initiatives that protect water quality, including stormwater management, stream corridor protection, and environmental education.

Context: Watershed

Beaver Dam Sanctuary

Page 15: Beaver Dam Sanctuary Master Plan

11Beaver Dam Sanctuary - Master Plan

Context: Natural Areas and Connectivity

Westchester County has a long history of providing a quiet refuge from New York City.

Today, this history is evident by the quantity of open space that protects water quality, provides recreation, and conserves habitat in an area speckled with estates and horse farms.

The New York City Department of Environmental Protection began protecting land in 1834, with the damming of the Croton River in Bedford, which created the City’s first upstate municipal supply reservoir. All the New York City DEP reservoirs are now surrounded by protected lands, about a quarter of which are open for recreation.

Further contributing to land protection in Bedford, the first property ever donated to The Nature Conservancy was the 225-acre Butler property, while the first preserve ever purchased by TNC was the 60-acre Mianus River Gorge Wildlife Refuge and Preserve acquired in 1954 and 1955, respectively. Today, the Butler Sanctuary is 363 acres and the Mianus River Gorge is 719 acres. The private Westmoreland Sanctuary was created in 1957 as a 625-acre nature preserve that provides environmental education programs to the community.

The Bedford Riding Lanes Association is a non-profit organization that began in 1920 to preserve, protect and maintain a system of country lanes and equestrian trails on public and private lands throughout Bedford. Originally, 50 miles of trails were open for use by the Association's 500 members. Today, there are more than 150 miles of trails, which continue to expand within Bedford and in adjacent towns, including the 1,600-acre Ward Pound Ridge Reservation in Pound Ridge. New additions include a large section of trails west of the Beaver Dam Sanctuary that recently reopened after years of neglect following the construction of the Saw Mill Parkway in the 1950s. The latest additions to the trail system include newly built trails at the John Jay Homestead, and in Mt. Kisco at the Butler Preserve, and the Merestead County Park, a 130-acre estate recently opened to the public. A working partnership with the Westchester Land Trust further enhances the successes of the BRLA through a conservation protection program. Besides easements on private properties, the land trust owns six preserves in Bedford that total 125 acres.

The BRLA maintains the entire trail system year-around by keeping the trails free of debris and fallen trees.

BRLA trails

Beaver Dam Sanctuary

Butler Preserve

John Jay Homestead State Park

Merestead

Ward Pound Ridge Reservation

Westmoreland Sanctuary

surronding protected open Mianus River Gorge

County Park surrounding protected natural areas

Page 16: Beaver Dam Sanctuary Master Plan

Section 12

Page 17: Beaver Dam Sanctuary Master Plan

13Beaver Dam Sanctuary - Master Plan

SECTION II ANALYSES

Page 18: Beaver Dam Sanctuary Master Plan

Section 14 II Analyses

Analysis: Habitat

Deciduous forest in wetland area Simpson Meadow Pair of mallards on the river

The Sanctuary contains many different habitat types that support a range of

vegetation and wildlife throughout the year.

Meadows are an ecosystem in decline in the northeast, where human development or farming often claims that space. Meadows are important to the life cycle of many small mammals, invertebrates, and grassland birds. Several grassland bird species, including the eastern meadowlark, field sparrow, and the bobolink, are becoming rare in the northeast due to lack of habitat. The meadows of the Beaver Dam Sanctuary provide diverse habitats. Simpson Meadow is the largest meadow of the Sanctuary. It contains groves of red cedars that provide valuable wildlife cover and food. The meadow just north of the Beaver Dam Road, along the Beaver Dam River, is the second largest meadow of the site and is valuable for its proximity to moving water and several mature white pines. The field to the east of the driveway of the private residence contains specimen sycamores, while the west side is a seasonal wet meadow. The remaining meadows are isolated by forest and provide important edge habitat.

Marshes along the perennial stream and within the floodplain of the BeaverDam River provide an important niche for many wildlife species in the area while protecting water quality. A variety of animals rely on marshes and wetlands during one or more stages of their lives to breed, mate, metamorphose, winter, and feed. Many plant species also rely on marshes for their survival. Open water provides habitat for mallards, wood ducks, great blue herons, Canada geese, and snapping turtles, as well as numerous invertebrates, amphibians, and mammals. The Beaver Dam River is stocked annually with brown and rainbow trout.

Mixed deciduous hardwood forests with 80-90 percent canopy cover most of the Sanctuary. The forests offer habitat for many small and large mammals as well as raptors and song birds. Lush tree and shrub growth offers shelter and breeding habitat for migrating birds; abundant and varied nuts (oaks, hickories, and beeches) and berries (blueberry, huckleberry, common juniper, serviceberry, spicebush, winterberry, dogwood, sumac, and viburnum) provide nourishment from summer through winter; and deep forest duff and dead wood on the ground provides cover for smaller animals throughout the winter. Standing dead trees are used by many wildlife species for food, shelter, and nests. Once these trees fall to the ground, they are used by other species, while decomposing and returning nutrients to the soil.

Simpson Meadow

Beaver DamRoad

Driveway

I-684

BeaverDam River

Page 19: Beaver Dam Sanctuary Master Plan

15Beaver Dam Sanctuary - Master Plan

Analysis: Hydrology

An abundance of water contributes to the biodiversity of the Sanctuary, while providing recreational opportunities.

Maintaining water quality is critical to the health of the Sanctuary and the watershed as a whole.

trails

BDS boundry

seasonal streams

marsh

rivers and Doc's Pond

flood plain

surrounding propertiesDoc’s Pond

The Beaver Dam River defines the southwest edge of the Sanctuary and flows north to join Broad Brook at a confluence in the Sanctuary

known as the Sheep Dip. Before entering the Sanctuary, Beaver Dam River flows through Ward Pound Ridge Reservation (see Natural Areas Context, page 11), flows through the lowlands of the Sanctuary, exits onto New York Department of Environmental Protection land and then goes on to the Muscoot Reservoir near Katonah. Broad Brook has its headwaters in The Nature Conservancy’s Butler Preserve in Mt. Kisco and passes a water sanitation facility at the Taconic Correctional Facility before entering the Sanctuary.

Seasonal streams in the Sanctuary drain toward the river from the east and one perennial stream flows north from Doc’s Pond and the surrounding marshes. Spring seeps occur throughout the Sanctuary, but are especially prominent on the slopes of the east side. These discharge wetlands can become seasonal streams or percolate water back into the soil. Seeps are valuable feeding sites for wildlife because they often remain free of snow in the winter and are among the first areas to become green in the spring. Plants associated with spring seeps in the Sanctuary include skunk cabbage, sedges, ferns, equisetum, marsh marigold, and wintergreen.

Beaver Dam River

BroadBrook

floodplain

Sheep Dip

I-684

Doc’s Pond

BeaverDam River

boundary

Page 20: Beaver Dam Sanctuary Master Plan

Section 16 II Analyses

Dominant tree species within the Sanctuary create six distinct forest types, each of which has unique characteristics that enhance biodiversity. These forest

types were identified by David Beers of Connwood Foresters, Inc. in 2003, while drafting a Forest Stewardship Plan for the Sanctuary. Below is a discussion of each type, including remarks about the fields. In all the forest types, most of the trees are 16 inches in diameter or greater, except for the lowland hardwoods, where the trees are mostly 12-16 inches in diameter. The mature oak/ash forest trees are typically larger than 20 inches in diameter.

Fertile hardwoods

Covering most of the northern half of the Sanctuary and the southern tip of the south half (60 acres total), this forest type prefers the lower slopes and floodplain of the Beaver Dam River. This stand has a diversity of deciduous trees, with the dominant species being sugar maple, hickory, white ash, beech, and red maple. Many large, old trees, including many awe-inspiring sycamores, are scattered throughout these two areas. The understory is dominated by Japanese barberry, which is especially obvious in the early spring when it is the only green shrub surrounded by pockets of spring ephemeral wildflowers, ferns, phlox, aster, and raspberry. Skunk cabbage occurs in isolated areas throughout the floodplain, denoting wetland areas. Besides barberry, prominent invasive vegetation in this forest type includes garlic mustard, multiflora rose, and Asiatic bittersweet.

Lowland hardwoods

Essentially a red maple swamp, this forest type covers about 9 acres that are divided by Beaver Dam Road. The soil in this area is saturated 5 to 7 months of the year, creating a valuable area for many wildlife species, while filtering and cleansing stormwater. Skunk cabbage, multiflora rose, barberry, phlox, and euonymus are found in the understory. Other tree species include white ash, elm, and locust.

Analysis: Forest Communities

Upland Oaks

LowlandHardwoods

Fertile Hardwoods

Fertile Hardwoods

MatureOak/Ash

Fields

YoungForest

NorthernHardwoods

Upland Oaks

LowlandHardwoods

Fields

Fields

Fieldsboundary

BeaverDam River

Simpson Meadow

BroadBrook

I-684

Beaver Dam Road

Page 21: Beaver Dam Sanctuary Master Plan

17Beaver Dam Sanctuary - Master Plan

Analysis: Forest Communities

Fields

Fields of the Sanctuary are varied in size and degree of isolation. The largest field, Simpson Meadow, is more than 15 acres, is easily accessible to trail users and maintenance crews, and allows for a variety of wildlife uses because of the large amount of forest edge and openness. The field to the north of Beaver Dam Road at the confluence of Beaver Dam River and Broad Brook is the second largest field. Both this smaller field and Simpson Meadow contain cross-country horse jumps and mowed paths. The other fields in the Sanctuary vary in size, and several are isolated by surrounding forest and lack of trails. This variety of sizes and seclusion should be valued and maintained because it helps support a range of biodiversity. For example, the larger fields provide breeding habitat and hunting grounds for many grassland birds and mammals, while the smaller, isolated forest openings cater to more sensitive species.

The meadows contain a diverse number of grass and forb species, yet lack many common meadow plants such as Canada lilies, asters, and ironweed. Healthy swaths of goldenrod, a plant disliked by deer, grow throughout the fields, especially Simpson’s Meadow, which also contains groves of red cedars. This is an early- succession species of great value to wildlife for its berries and as cover. Deer have browsed the cedars up to 7 feet high by deer and barberry grows around the base in the disturbed soil, which cannot easily be reached by the equipment used to mow the fields.

Mature oak/ash

This transitional forest covers the entire east side of the southern portion of the Sanctuary on a slope of 15 percent or greater. The majority of this area is covered by mature black oaks and white ash, while the understory is thick with invasive vegetation. As the dominant trees die of age and disease (including ash decline), the understory vegetation competes for the resulting forest opening to either mature into another canopy tree or naturalize the new sunny area. In this area, the invasive vegetation overwhelms and outcompetes the native understory (which is already stressed from the steady browsing by the deer) to fill the new opening.

Northern hardwoods

Most of the southern half of the Sanctuary is a northern hardwood forest that comprises about 25 acres. Dominated by red maples, beech, black birch, and sugar maple, this area also boasts several stands of hemlocks. Several dense pockets of barberry exist in this area, becoming more prominent in proximity to the Beaver Dam Road.

Upland oaks

The drier, thinner soils in the Chatfield-Charlton series (see Soils map and description, page 18) define this steeply sloping 22-acre forest of red maple, black and white oaks, hickory, black birch, and sugar maple. The understory here is more open than the fertile hardwood forest to the south, yet thick patches of bittersweet and honeysuckle exist, especially where the forest opens to Simpson Meadow.

Young forest

The forest surrounding the two fields just north of Beaver Dam Road are in transition from use as pasture within the last 100 years, to the young forest/shrub land that exists today. Fast-growing, large white pines border the existing maintained fields in this area, while the small deciduous tree species include hop hornbeam, maples, oaks, elms, birches, hickory, ash, beech, and sycamore. Stands of invasive species such as autumn olive, honeysuckle, and multiflora rose create impenetrable barriers for walkers and reduce biodiversity by limiting the regeneration of native species.

Page 22: Beaver Dam Sanctuary Master Plan

Section 18 II Analyses

Analysis: Soil

Rock outcrop

Hydric soils A hoof print in stable soils provide for a safe ride

The primarily soils in the Beaver Dam Sanctuary are loamy soils, which is ideal for trails because

they are stable, durable, and well draining. The well- to excessively well-draining soils in the most northern tip of the Sanctuary and south of the Beaver Dam Road, are shallower, do not hold nutrients and moisture as well, and contain areas of exposed bedrock. Trails through these stable soil types should tolerate heavy use well.

The most southern portion of the Sanctuary, along Beaver Dam River and including the Ford, contains moderately well drained to somewhat poorly drained soil with a moderate-to-rapid permeability rate and low runoff rate. The water table in this series is within 12 inches of the surface during the winter and spring, and after precipitation. Muddy areas form easily on trails of this soil type when wet and bank stabilizing is crucial to avoid trenching and erosion.

Hydric soils are found along the perennial stream and in the floodplain of Beaver Dam River where it leaves the Sanctuary on the west. These silty soils are saturated seven to nine months of the year and are typical of wetlands and red maple swamps. The timing and amount of trail use through these sensitive areas should be controlled, as these soils are susceptible to erosion and care must be taken to maintain properly constructed trails.

BeaverDam River

Beaver Dam Road

The Ford

boundary

Page 23: Beaver Dam Sanctuary Master Plan

19Beaver Dam Sanctuary - Master Plan

¯ 0 500 1,000250Feet

Analysis: Slopes and Drainage

I-684 Property Beaver Dam Property Private Rte 22

Line River Line Residence

water flow direction

river flow direction

Broad Brook

The Sanctuary drains toward Broad Brook and Beaver Dam River, where the elevation at its lowest is 220’ above sea level. In the

southern half of the Sanctuary below Beaver Dam Road (which contains the highest elevation of 340’), drainage is consistently from east to west. The northern half also slopes from east to west, yet as the River moves toward the center of the Sanctuary, the slope increases toward the west. Simpson Meadow in the north mostly drains to the west.

Stormwater runoff through the Sanctuary may lead to nonpoint-source pollution from erosion and sedimentation. For the health of the ecosystem, and because the Beaver Dam River flows into the Muscoot Reservoir, one of the contributing water bodies to the New York City drinking water supply, protective measures are essential.

BeaverDam River

BroadBrook

I-684

Beaver Dam Road

10’ contour lines

Page 24: Beaver Dam Sanctuary Master Plan

Section 20 II Analyses

Analysis: Trails

A trail along a stone wallSimpson Meadow with red cedarsTrail along the Beaver Dam River

Page 25: Beaver Dam Sanctuary Master Plan

21Beaver Dam Sanctuary - Master Plan

Analysis: Trails (cont.)

Carriage road Cross country jump Opening into Simpson

Trails extend throughout the Beaver Dam Sanctuary. This includes the floodplain, the slope to the east, the meadows, both sides of Broad

Brook and Beaver Dam River, and past the wetlands to Doc’s Pond. Many of the trails extend beyond the boundaries of the Sanctuary to join the network of trails protected by the Bedford Riding Lanes Association, which travel over public and private lands.

Trails within the Sanctuary range from narrow paths through the forest to old carriage roads along Beaver Dam River. In the Simpson Meadow and the field along the Beaver Dam Road, mown paths direct equestrians through seas of tall grasses to cross-country jumps. The trails cross the Beaver Dam River in four places and Broad Brook twice. Along the river, the crossing furthest to the south is known as the Ford and ties the Sanctuary to adjacent residential properties and the BRLA trail network. All the other crossings link the two sides of the Sanctuary bisected by Broad Brook and the Beaver Dam River.

Cross-country jumps are found along the trails. Where jumps are located in the forest, short trails provide detours for hikers, skiers, and equestrians not wishing to jump. Additional side trails (known as volunteer or outlaw trails) exist as short- cuts or routes to avoid wet areas or downed trees. Poorly marked trails through open areas encourage even more redundant trails when users create their own paths. Redundant trails create additional impact by increasing erosion, compacting the soil, and disturbing the surrounding vegetation. These outlaw trails encourage the creation of additional paths and the resulting disturbed areas provide desirable conditions for the invasion of exotic plants.

BroadBrook

BeaverDam River

Doc’s Pond

I-684

Page 26: Beaver Dam Sanctuary Master Plan

Section 22

Page 27: Beaver Dam Sanctuary Master Plan

23Beaver Dam Sanctuary - Master Plan

SECTION III MANAGEMENT PLAN

Page 28: Beaver Dam Sanctuary Master Plan

Section 24 III Management Plan

Peering through white pines at the isolated meadow by the young forest.A series of cross-country jumps in a field on the southern side of the Sanctuary. Canada geese on Doc’s Pond.

Page 29: Beaver Dam Sanctuary Master Plan

25Beaver Dam Sanctuary - Master Plan

Proposed Plan

The proposed plan for the Beaver Dam Sanctuary recommends management

practices to achieve the goals of the master plan. Specific practices are proposed for managing:• The trail system • Stormwater• Meadows• Forests

Wildlife•

This final trail map is based on the identified sensitive areas and degraded trails in the analyses section and the priority trail management areas. Year-round trails, (in red) should be monitored regularly to safeguard against overuse. Some trails (in green) directly affect water quality and should be closed every spring. One to three deer exclosures (approximately 30’ by 30’) should be located in the mature oak/ash forest (in yellow) and the young forest/shrubland (in purple) to assist forest regeneration and invasive species control.

0 500 1,000250Feet¯

year-round trails

spring closures

BRLA trails

Mature Oak/Ash

Young Forest

water

BroadBrook

BeaverDam River

Doc’s Pond

I-684

Page 30: Beaver Dam Sanctuary Master Plan

Section 26 III Management Plan

Trails Management for the trail system

Recommended Trail Standards

TRAILUSER

AVERAGESPEED(mph)

LONGITUDINALSLOPE(max)

CROSSSLOPE(max)

CURVERADIUS

(feet)

VERTICALCLEARANCE

(feet)

MINIMUMWIDTH(feet)

Pedestrian 3 - 7 No restriction 5% 50 7 3 - 5Equestrian 5-15 10% 5% 100 10 5

Skier 2 - 8 5% 5% 50 7 5

Overview

Most of the soils in the Beaver Dam Sanctuary are suitable for trails. However, there are sensitive areas where the

watertable is close to the surface and where water flows across or along the trail. Other problem areas exist where redundant or unauthorized volunteer trails adjacent to existing paths create sections of trampled vegetation and compacted ground; other trails run straight down slopes over 10 degrees. These areas require restoration and maintenance to reduce impact and prevent disturbance to the surrounding habitat. Some of the trail sections may require seasonal or long-term closures to rehabilitate the forest and the entire system should be regularly monitored.

Trail Monitoring and Maintenance

The maintenance objectives must adhere to the principles that serve the goals of user safety, environmental soundness, and economic sustainability. Adequate corridor and tread dimensions, tread condition, and appropriate design of bridging and crossings are primary issues in user safety. Environmental soundness issues focus on erosion prevention and protection of water quality protection, and habitat conservation. Regular maintenance of trails can extend the life and preclude the need for major repairs and permanent closures in the long term.

There are a number of variables that can add to trail maintenance requirements, including location (e.g., on a steep slope or in a floodplain), soil type, and current problems. Inadequate drainage is a factor that often causes and can exacerbate trail issues and, therefore, should be one of the first problems to be remedied.

General trail management recommendations:

Inspect the entire trail system at least twice a year for damage. • Maintain adequate cross-slope for proper drainage (page 29) and install water bars and culverts (page 30) where needed.

Every spring, close the crossings and trails on the west side to • all users. During that time, maintenance should be performed to rehabilitate crossings and trails should not be reopened until conditions are stable. (See final map on page 24 and water crossings on page 31.)

Every spring, trails through sensitive wet areas should be • closed to all users every spring. (See final trail map, page 24.)

Action plan: Priority 1: Maintain the southern crossing, known as the Ford and surrounding trails to protect water quality and prevent trenching. See water crossings, page 31 and trenching, page 28.

Priority 2: Trails in wet areas should be raised and runoff should be diverted appropriately. See turnpikes, page 29 and water diversion techniques, page 30.

Priority 3: Trenched trails (especially the bottom 100-foot section that leads from the river to the southeast side of Simpson Meadow) should be filled to prevent erosion and to avoid the possibility of permanent closure. See page 28.

Priority 4: River crossings should be stabilized to protect water quality. See page 31.

Maintain proper corridor widths.

Page 31: Beaver Dam Sanctuary Master Plan

27Beaver Dam Sanctuary - Master PlanIII Management Areas

This trails management map shows trails in various conditions, including those that are stable and require regular monitoring and maintenance

(see page 27-28). The entrenched trails are found in three areas and should be filled, compacted, and stabilized (see page 27) to reduce erosion and preserve water quality. Trails in wet areas are to be raised, hardened and seasonally closed. Recommendations for repairing these trail types are found on pages 27 and 28. Redundant trails require proper closures, as described on page 30. Trails along or up steep slopes are shown in gray.

Monitoring for erosion is crucial and techniques found on page 28 should be used to divert runoff and stabilize trails. Three stream crossings are used to access the west side of the Sanctuary above the confluence of Broad Brook and Beaver Dam River, making this area especially susceptible to impact during the spring. Therefore, this area should be closed to all users during wet months to prevent damage to the crossings and protect water quality; and should not open until they have been properly stabilized. The crossing on the north side of Beaver Dam Road should be closed in the spring as well; however, the crossing in the south should remain open, as it links the property to BRLA trails. Therefore maintenance to this area, known as the Ford, should be a priority.

Trails Management for the trail system

Entrenched trails, such as the areas shown in purple, should be filled and outsloped to mitigate erosion (priority 3). Trails through poorly drained soils should be stabilized (priority 2) to protect water quality and those in sensitive area should be closed seasonally, including all the trails and crossings on the west side (priority 4).

The Ford and surrounding trails should be filled, stabilized, compacted, and annually evaluated (priority 1).

A

A

B

B

BroadBrook

BeaverDam River

I-684

Beaver Dam Road

The Ford

Simpson Meadow

Page 32: Beaver Dam Sanctuary Master Plan

Section 28 III Management Areas

Trails

A: Deep trenching

A trenched trail causes users to feel as though they are walking in the bottom of a half-pipe. Most of the river crossings in the Sanctuary are trenched, with the worst section located at the bottom 100 feet of the trail that connects Beaver Dam River to the southeast side of Simpson Meadow. Without proper maintenance, trenched trails worsen with every storm event, as runoff cuts deeper and increases the flow of water. A major threat to water quality, trenched trails require immediate attention.

B: Short cuts

Frequently, trail users travel the shortest distance between two points, disregarding the designated paths of travel. This creates a web of trails, which sometimes travel through open wet areas (such as the north end of Doc’s Pond) or between steep trail sections, which can lead to major erosion problems. To prevent this, trails should be clearly marked and properly maintained so it is easier to remain on them than to go around. Short cut trails should be closed and rehabilitated in order to prevent future use.

D: Excessive widening

Trails can become widened from a single or double track to a “freeway” of several parallel tracks. This especially occurs in the Sanctuary within the floodplain of the Beaver Dam River where trail users enlarge the trail or make new trails while trying to avoid wet and muddy areas.

C: Saturated trails

Even small areas with wet soils can deteriorate rapidly into muddy areas, degrading natural resources, such as water quality and positive user experiences. These impacts can be avoided by raising and compacting the tread.

AB

C

D

Example locations of trailmaintenance areas

Trails

General characteristics that designate a poorly maintained or constructed trail:

0 500 1,000250Feet¯

inspect annually and maintain

dead end = remove

entrenched = repair and maintain

harden and close in spring

harden trail in wet areas

hydric = repair and maintain

redundant = remove

BRLA trails

Highways

Major Roads

Residental Streets

BDS boundry

water

private property in BDS

surrounding parcels

TRAIL RECOMMENDATIONS (DRAFT)

A

D

B

C

Management for the trail system (cont.)

Page 33: Beaver Dam Sanctuary Master Plan

29Beaver Dam Sanctuary - Master Plan

Steep slope with tread at 90° from contour line. A switchback would drain water away from tread.

Drainage

water

CROSS SLOPE

A 5% cross slope allows water toflow downwards.

Switchback

At a minimum, biannual inspections looking for damaged sections should be performed along the entire network of trails in the Sanctuary. When erosion problems are evident, water may be the

cause and determining where to divert it is critical. Trail building practices that should be used for repair and maintenance of the entire trail system follow.

Trails Management for the trail system (cont.)

TREAD

DRAINAGE

Maintain the cross-slope

The cross-slope is defined as a slight tilt of the trail. This is the first order of business in trail maintenance. It is the simplest, but most labor intensive trail maintenance procedure. The cross-slope is maintained by simply pulling the berm back into the trail tread. This must be done consistently and maintained to allow proper drainage and prevent water from flowing down the trail.

Switchbacks are utilized where it is necessary to change the direction of the trail on a hill. For trails steeper than 15%, switchbacks can provide an easier walk and also help divert water.

Turnpikes

Turnpikes are used to prevent trenching and the common scenario of trail users creating braided trails to avoid rutted and wet areas, while still allowing water movement beneath. In generally flat areas, turnpikes raise the crowned tread slightly above the existing ground level with gravel and curbing timbers. Treads can also be created with timbers surrounding a gravel-geotextile combination, which stands up well to heavy equestrian use. Curbing is not needed if only gravel is used, yet the curbing helps define the trail, reduce maintenance, and is necessary if geotextile is used. The trail surface between the curbing should be 5-6 feet wide to allow easy movement and access by maintenance equipment. Ditches on either side of the new turnpike provide material to raise the trail while draining water away.

Elevated tread with curbing Elevated tread

Center crowning Corduroy Trail

STONE RETAININGWALL

Trail Drain

Steep slope with tread at 90° from contour line. A switchback would drain water away from tread.

A turnpike here would allow water to flow across the trail and provide a more stable tread, allowing the trail to remain dry and stable.

Page 34: Beaver Dam Sanctuary Master Plan

Section 30 III Management Areas

Install and maintain water bars

Water bars divert water off a trail at controlled points. Done well, a series of water bars can effectively eliminate most erosion along a trail and stabilize it for years. Done poorly, water bars can accentuate trail erosion and become dangerous tripping hazards. Effective water bars can be made from native rock obtained on-site. When rock of a suitable size is not available, water bars can be made from 4x6-foot, 6- to 8-inch diameter non-pressure treated timber, or rot-resistant native logs such as white oak, hemlock, and black locust. Placing water bars at a 60 degree angle encourages water to move away and not pool. The downslope end of the water bar needs to be periodically graded out to assure that water flows off the trail. Without regular maintenance, a water bar is useless and can be counterproductive.

TREADWater isdiverted away from treadTread

As water flows down into upslope ditch, the remaining water infiltrates into downslope ditch.

Install diversion ditches/swales

Ditches allow drainage parallel to the trail, while still slowing and infiltrating water and swales are constructed to convey water into a vegetated area. A good ditch is shaped and lined using the appropriate vegetative or structural material and does not cause flooding, erosion, or sedimentation.

Maintain drainage dips A drainage dip is literally a dip in the trail that sheds and diverts water. Like a water bar, it only remains an effective means of erosion prevention if regular maintenance is performed.

TREAD

Retaining walls

A retaining wall or stone cribbing is a structure of stone or wood designed to stabilize the trail base on steeper side slopes.

Trails Management for the trail system (cont.)

Maintenance techniques to divert water from trail tread should occur along all trails in the Sanctuary

Culverts

In wet areas and at the bottom of slopes, culverts (either open-top or closed) can be used to move water across the trail from one side to the other without washing out the surface. They are low cost and not labor-intensive alternatives to small bridges. They can be used to accommodate water flow from either spring runoff or small streams. It is important to keep culverts free of debris or they may plug up and become ineffective. In areas of moving surface water (from seasonal streams or storm events), culverts may be placed to allow water to flow past the trail. The spacing and size of the culverts depends on the site requirements, though 6- to 10-inch diameter culverts are typically adequate. Attention must be given to the design and installation of culverts, as they can negatively affect migrating wetland wildlife species.

DRAINAGE

WATER BAR

Drainage

-

10% grade

-

10% grade

+10% grade

DRAINAGE DIP

Wall

III Management Areas

Waterflow

TREAD

Page 35: Beaver Dam Sanctuary Master Plan

31Beaver Dam Sanctuary - Master Plan

Bridges

Descending steep embankments can be dangerous to riders and hikers. A steeply descending trail is also a source of erosion that can degrade stream quality. The clearance of the bridge must provide for passage of flood water, ice, and debris above the high water mark. Stream crossings should be at a 90-degree angle with a straight, level approach. The master plan is not recommending a bridge for the fords, as the water level permits crossings; however, buffers should be stabilized to provide for a safe crossing.

Water Crossings

For water quality protection, the Sanctuary should keep water crossings to a minimum, as bank disturbance increases sediment loading in streams. Fords can be used to traverse slow-moving streams less than 24-inches deep. Crossings should have a gentle slope, stable banks, and gravel or sand bottoms. Before initiating any project, contact the New York Department of Environmental Protection to attain any required permits. State jurisdiction over the use of protected waters and wetlands generally begins at the high water mark.

Crossing along Beaver Dam River

Trails Management for the trail system (cont.)

Crossings should be filled and stabilized An easy and safe crossing along Beaver Dam River A trenched water crossing

Crossing at a 90° angleIII Management Areas

Page 36: Beaver Dam Sanctuary Master Plan

Section 32 III Management Areas

Restoring closed trails

Redundant trails should be closed and rehabilitated in a way that stops further use, prevents invasions by exotic vegetation, and assists the establishment of native plants. Steps for proper closure include roping off the entrances, posting an interpretive sign, and loosening the soil and raking over the forest duff to create an intact appearance. Native vegetation (nursery propagated or transplanted from elsewhere on site) should be then be planted into the closed area or at least until the trail bends out of sight.

Using fill material

A deeply trenched trail can be restored by using on-site soil and stones or importing gravel, compacting it, and creating a well-drained cross-sloped trail. Trails should be graded smooth and maintained at about 90 percent compaction on a routine basis. In some situations, this approach may be both cost prohibitive and labor intensive, making the more suitable option to permanently close the trail. Because of this, it is crucial that the restoration of the entrenched trails in the Sanctuary become a priority before they become damaged beyond repair (or should be closed if they are redundant).

Materials

Trail structures should be built of long-lasting material and designed to blend with the surroundings. Minor structures such as turnpikes, retaining walls, culverts, and small bridges can be built of suitable native materials. Rocks make longer-lasting retaining walls and water bars than wood, though certain species of hardwood are quite durable and aesthetically pleasing. The most durable, local materials should be used to minimize both embodied energy and maintenance costs. When on-site materials are used, the source area should be left in as natural a state as possible.

Pruning

Regular vegetation pruning is an essential part of trail maintenance. All overhanging branches and limbs must be cut back beyond 10 feet of the trail for the safety of horses and riders. When removing vegetation, sensitivity should be given to maintaining a natural appearance of the surrounding area and not making overly obvious cuts to trees and shrubs.

Trail sign material

Wooden signs blend with the landscape and should be made from decay resistant species, such as black locust. Posts should be at least 6-feet long, 4-inches wide and accommodate 3-inch letters

Directional signs assist users with wayfinding.

Restoration Area

Please help protect the Sanctuary; stay on trail

Trails

Interpretive signs communicate to the users land management and stewardship responsibilities and also educate users about

on-trail resource impacts, trail restrictions, restoration activities, and the impact of

invasive species on the health of an ecosystem.

Branchcollar

Management for the trail system (cont.)

Interpretive signs

By guiding, informing, and identifying, signs will serve a practical purpose and also promote environmental awareness and create a positive impression of care and good stewardship of the land. Trail signs are necessary for user safety and to protect trails and surrounding habitat. Interpretive signs should be concise and easily understood with information stated in simple complete sentences. Materials, sizes, and color of all signs should be uniform. Finally, the signs should not compete with the surroundings but complement them. During the implementation of the master plan, many subtle changes and several obvious restoration projects may draw the attention of the trail users. Aligned with the goals of the master plan (to act as a model to the community) and the Sanctuary (to promote environmental education), interpretive signs should engage users while they learn good stewardship principles that they can apply to their own property.

Regular maintenance should include the upkeep and replacement of signs.

Page 37: Beaver Dam Sanctuary Master Plan

33Beaver Dam Sanctuary - Master Plan

TrailsEstimated costs

Redundant trails: Restoration includes barrier (two posts and rope), signs, native plants, deer protection, and labor. Cost based on 20-foot average length of restoration, raking the trail, and plants (30 native plants at 30 inches on center).

Entrenched trails: soil and gravel fill, geotextile and labor (including compaction).

Saturated trails: soil and gravel fill, geotextile and labor. (Less fill is required than entrenched trails).

Culverts: pipe, gravel, labor. Culverts must be designed properly so they don’t interfere with migrating wildlife.

Eroded and wet trails: waterbars (logs) and labor.

Deer exclosure: 8-foot high fencing, posts, labor.

River crossings: soil and gravel fill and labor (including compaction).

Processes are labor intensive; volunteer assistance may decrease the cost.

SITUATIONS RECOMMENDATIONS ESTIMATED COST

Redundant trails trail closure $400 - $500 per closure

Entrenched trails fill, stabilization, compaction $6-$8 per linear foot of trail Saturated trails tread raising and stabilization $3 - $4 per linear foot of trail Seasonal stream properly designed culverts $20-$25 per linear foot of trailcrossing and other techniques Eroded and wet trails water diversion techniques $15-$20 per linear foot of trail Deer deer exclosures $3 per square foot River crossings fill and compaction $8-$12 per square foot

Management for the trail system (cont.)

Trails provide recreation and an opportunity to appreciate nature

Page 38: Beaver Dam Sanctuary Master Plan

Section 34 III Management Areas

Promoting water quality and healthy aquatic habitats at the Beaver Dam Sanctuary should

include the installation of erosion control, sediment catchment, and water infiltration systems. Currently at the Sanctuary few methods are implemented to deal with the water quality problems associated with erosion and the resulting sediments that wash into the Beaver Dam River.

This master plan recommends trail improvements that will divert water off trail and reduce erosion once implemented. Closing redundant trails and minimizing off-trail travel will reduce soil compaction, which can greatly affect the soil’s ability to absorb water. As well, the forest management suggestions on pages 38-39 will help control erosion along slopes and minimize runoff, once the healthy understory is restored. Controlling the runoff along the forested slopes and trails reduces the risk of non-point source pollution such as fertilizers and waste from surrounding residential properties and horse paddocks.

The largest threat to water quality and aquatic habitat in the Sanctuary is runoff from Beaver Dam Road. Sediments washed into the river from the road can be fatal to aquatic wildlife, as it can increase turbidity, making it difficult for aquatic plants to photosynthesize, clogging fish gills, filling spawning and breeding grounds, smothering benthic communities, and reduced visibility for both predators and prey. Sedimentation can also carry nutrients that lead to eutrophication, the result of excess nutrients in the water that causes algae to overproduce, which depletes available oxygen and causes aquatic animals to die. Stormwater runoff carries sediment which fills and clogs wetlands, reducing their ability to clean and infiltrate runoff and impacting water quality in the entire micro-watershed. It also increases the chance of floods.

Beaver Dam Road is a town maintained gravel road that currently has several sediment catchment basins in place to detain and filter water that runs off the sloped road. Ditches alongside the road direct water to the basins, which are simple depressions dug into the side of the road. This conventional method is maintenance intensive, as no pretreatment exists to manage sediment-laden runoff from the source down. A more effective stormwater design can be implemented that requires less maintenance and pretreats the runoff before entering Beaver Dam River and, ultimately, the New York City municipal water supply by following Low Impact Development (LID) principles and the Best Management Practices on the following two pages.

Stormwater management

Stormwater percolates through an uncompacted forest floor (left), but not as readily in a compacted area.

Low Impact Development is an approach to land development (or re-development) that works with nature to manage stormwater as close to its source as possible. LID employs principles such as preserving and recreating natural landscape features, minimizing effective imperviousness to create functional and appealing site drainage that treat stormwater as a resource rather than a waste product. There are many practices that have been used to adhere to these principles such as bioretention facilities, rain gardens, vegetated rooftops, rain barrels, and permeable pavements. By implementing LID principles and practices, water can be managed in a way that reduces the impact of built areas and promotes the natural movement of water within an ecosystem or watershed. Applied on a broad scale, LID can maintain or restore a watershed's hydrologic and ecological functions. LID has been characterized as a sustainable stormwater practice by the Water Environment Research Foundation and others.-EPA website

Beaver Dam Road

Sediment catchment basin along Beaver Dam Road

Page 39: Beaver Dam Sanctuary Master Plan

35Beaver Dam Sanctuary - Master Plan

Stormwater management (cont.)

Vegetated swales

Vegetated swales essentially are ditches lined with vegetation, which stabilize soil, reduce water velocity, catch sediment, and promote infiltration. Check dams within these swales further assist in slowing water and allowing it to infiltrate. In the early stages of creating vegetated swales, the functions performed by check dams enable vegetation to become established. These swales should be planted in the dry season to allow the plants to become established before the impacts of flowing water are introduced.

Sediment catchment basins are conventional stormwater treatment facilities that are very efficient when used in conjunction with LID. These basins collect water in the catch basin, where sediment settles out and remains in the basin as the water is released through the outflow pipe. Sediment catchment basins must be cleaned out once a season to every few years, depending on the sediment loads and pretreatment practices. When used in combination with other stormwater practices described above, the loads will be reduced drastically as the bioretention basins, vegetated swales, or diversion berms are installed.

Sediment catchment trap with catch basin

The following diagrams demonstrate stormwater management practices that are recommended to be used along Beaver Dam Road to protect water quality.

Bioretention basins are small vegetated depressions that filter stormwater runoff before releasing it via infiltration or to an outlet. Generally, bioretention basins are small in size (typically 12’ x18’ or smaller). In residential areas, these bioretention basins are known as rain gardens and treat runoff from impervious areas such as driveways, patios, and roof tops.

Bioretention basins

Page 40: Beaver Dam Sanctuary Master Plan

Section 36 III Management Areas

Properly designed culverts should be installed in areas where water must be moved from one side of the trail or road to another to prevent erosion. The released water should flow onto a stable area, such as a rip-rap apron that reduces the chance of trenching from the force of the released water. In areas receiving high flows, a bioretention basin is recommended below the outflow to encourage infiltration.

Filter berms

Filter berms slow and divert water and are useful on slopes and above stream crossings to prevent water from eroding trails and creating channels. Berms may eventually become vegetated and take on a more natural look.

On Beaver Dam Road, maintaining a road crown by sloping the surface will ensure water will not flow down the middle of the road but will enter drainage ditches and be directed to the new bioretention basins placed along the length of the road. As mentioned in the trail section on trail building and maintenance techniques, page 29, maintaining the proper slope is a basic step in erosion control.

Road crown

Stormwater management (cont.)

Rip rap apron

Page 41: Beaver Dam Sanctuary Master Plan

37Beaver Dam Sanctuary - Master Plan

Meadow Management

Weed-free hay

Horses can introduce exotic species through seeds in their manure. In the western United States where trail riding is a more wide-spread activity, national parks and state forests require horses be fed certified weed-free hay to control noxious weed invasions along trails. In the east, demand for certified weed-free hay is slowly growing as people become aware of the negative impact exotic vegetation has on the ecosystems they enjoy riding their horses through. The Beaver Dam Sanctuary can assist this movement by bringing awareness to the equestrian trail users and by encouraging them to request that area hay farmers become certified. For more information, see the brochure from the North American Weed Management Association in the appendix.

The meadows of the Beaver Dam Sanctuary are currently mowed with a tractor annually in the early winter. This regime is the

preferred management practice for wildlife in the short term, as it ensures all plants have gone to seed and does not disturb wildlife nesting areas in the spring. Care should be taken that the tractor is set to cut the grass between 6 and 12 inches above the ground because insects (an important food source of birds) rely on the remaining shafts of grass as shelter during the winter months. In addition, the cut grass and forbs provide nutrients to the soil, protect fragile new growth, and create winter cover for wildlife.

If controlling invasive vegetation is the management goal, it is best accomplished by mowing in the early to mid-summer after the migrant songbirds have nested and the young have fledged. At this time, the non-native cool season grasses are about to go to seed, which can be prevented by mowing. Mowing will slow the growth of invasive woody plant species that encroach on the meadows from the forest edge and that are spread by birds. Early summer mowing knocks back woody vegetation that is about to flower and has most of its energy above ground (as opposed to fall and winter when the plant’s energy is stored in its roots). Regular mowing retards the growth of woody vegetation by depleting that energy and eventually causes the plants’ demise. This includes Japanese barberry growing under the red cedars in Simpson’s Meadow, which currently produce a large seed bank that makes meadow management more difficult. These existing cedars, however, should be encouraged to grow because they support the meadow ecology by providing berries and beneficial cover to wildlife.

If the summer mowing regime is followed annually, there should be a reduction of invasive species within a few years, at which point, and with monitoring, mowing may only be necessary every few years, excluding the annually mown paths.

Mowing controls the growth of invasive plants

Meadows provide valuable wildlife cover and food

Page 42: Beaver Dam Sanctuary Master Plan

Section 38 III Management Areas

Forest management

In the Beaver Dam Sanctuary, forest management is necessary to restore the understory, control invasive vegetation, and maintain a healthy

ecosystem. The entire property should be regularly monitored, but forest management should focus on two areas, the mature oak/ash forest on the southeast side and the young forest/shrubland northwest of Beaver Dam Road. Because these two areas are in transition, management will be crucial throughout the different stages to achieve a desirable outcome. Proper forest management will not only protect native species and provide valuable habitat, but will also promote water quality.

Managing succession

Managing for succession in the Sanctuary will support biodiversity by providing a range of habitat types that will attract an array of species in different life stages. It also maintains forests of different ages and species compositions, providing some insurance that when disturbances occur, they will not wipe out an entire area. However, localized disturbances are actually required for all ecosystems to have healthy regeneration and to maintain the different stages that are necessary for a diverse habitat.

Ecosystems are in a dynamic equilibrium (a give-and-take) with short- and long-term changes that fluctuate over time. The amount and composition of plant and animal populations change in conjunction with disturbances that occur at different scales and levels of intensity. As one community changes from environmental stresses, all other associated communities also change, often affecting a much larger web and the effect ripples outward. Therefore, changes to animal communities affect plant communities and vice versa. Besides these spatial fluctuations, structural changes also occur temporally in a process known as succession. Ecosystems undergo changes over time from natural and human-incuced disturbances such as an abandoned farm pasture revert into mature forests. With the changes of those plant communities come changes of the wildlife found within them. For example, a grassland bird does not live in a dense forest, while a forest dweller, such as a squirrel is not adapted to meadow life away from trees. Succession happens in stages over time, yet can be accelerated or suppressed through human manipulation to produce a chosen outcome.

Ecological restoration in the Sanctuary’s mature oak/ash forest should include enclosed areas of one or two acres in size that will exclude deer and allow understory vegetation to become established. With the removal of exotic vegetation and the absence of deer, native plants will be allowed to mature, at which point the fences should be removed. These enclosed areas will provide boundaries for intensive control of exotic vegetation. The fenced plots will also provide an educational component as users will be able to compare the difference in forest composition between managed and unmanaged areas.

Areas within the young forest/shrubland to the northwest of Beaver Dam Road should also be protected with deer exclosures and managed as an early- to mid-successional forest. To accomplish this, the plots should be selectively cleared to allow undappled sunlight to reach the ground. The many mature white pines, which are mid-successional trees, should be valued because they offer important cover habitat in the Sanctuary. Meadow plants, such as goldenrod and asters, which currently exist in this area, should be encouraged to remain through selective mowing and supplemental plantings, because their thick growth prevents growth of woody vegetation (for more discussion on the impacts of deer and deer exclosure, see page 41).

Mature oak / ash

Young forest

Page 43: Beaver Dam Sanctuary Master Plan

39Beaver Dam Sanctuary - Master Plan

Forest management (cont.)

Effects of vegetation on erosion and sedimentation

Revegetation is a key method for stabilizing sites disturbed by unregulated use and over-browsing by deer. The establishment of suitable vegetative cover affords erosion protection and sedimentation control by intercepting precipitation, shielding the soil surface from overland flow, and reducing water velocity. Additionally, plant roots hold the soil in place and promote infiltration.

Mulches

Applying a thin layer of mulch to a revegetated site performs crucial short-term services while the plants are becoming mature. Mulches mimic the natural soil cover by adding organic matter, providing a substrate for beneficial microorganisms, retaining moisture, controlling erosion, moderating soil temperature fluctuations, and aiding weed suppression. To avoid erosion, as soon as possible, mulch (made from downed trees on site) should be applied no more than 3 to 4 inches deep to bare ground.

Asiatic Bittersweet (Celastrus orbiculatus)

Common Reed(Phragmites australis)

Winged Euonymus (Euonymus alata)

Japanese Knotweed(Polygonum cuspidatum)

Honeysuckle (Loniera spp)

Multiflora Rose(Rosa multiflora)

Garlic Mustard(Alliaria petiolata)

Japanese Barberry(Berberis thumbergii)

Invasive plants

In the Beaver Dam Sanctuary, invasive plants have degraded the composition, structure, and ecology of the forests by outcompeting and displacing native vegetation, which impacts wildlife habitat. The removal of exotic vegetation is initially an intensive process that requires long-term monitoring and maintenance. Species removal techniques must continue, as species react differently to common removal processes. For more information, see the the appendix detailed description list of invasive plants.

Page 44: Beaver Dam Sanctuary Master Plan

Section 40 III Management Areas

Birds that require early-successional forests:

Ruffled grouseBlack-billed cuckooYellow-billed cuckooWillow flycatcherNorthern flickerWinter wrenVeeryEastern bluebirdGray catbirdBrown thrasherCedar waxwingIndigo buntingRose-breasted grosbeakAmerican redstartBlue-winged warblerNashville warblerChestnut-sided warblerPrairie warblerField sparrow American goldfinch

Ruffled grouse

Eastern meadowlark

Managing for succession in the Sanctuary will support biodiversity by providing a range of habitat types that will attract an array of species in different life stages

Wildlife management

Early succession species that favor open areas with sunlight, annual and perennial plant, shrubs, insects and many bird species including raptors.

Forest dwellers, mast feeders, herbivores, carnivores, and hibernators favor uneven-aged stands.

Transitional zone

Early-Succession Mid-Succession Late-Succession

Page 45: Beaver Dam Sanctuary Master Plan

41Beaver Dam Sanctuary - Master Plan

White-tailed Deer (Odocoileus virginianus)

Through their selective feeding on seedlings, young trees, tree sprouts, and other low vegetation, white-tailed deer can have a

strong impact on vegetation development and the species composition of forests, leading to degraded conditions and reduced biodiversity. In the Beaver Dam Sanctuary, intense browsing by the large deer population is having a significant impact on forest undergrowth, inhibiting tree and shrub regeneration and eliminating or reducing populations of woodland wildflowers. Some browse-resistant non-native plants, such as Japanese Barberry, honeysuckle, garlic mustard, and Asiatic bittersweet have increased as more palatable native competitors decline due to browsing.

One goal of deer management is to maintain populations below levels which they cause damage. The elimination of natural predators in the northeast has drastically thrown off the balance in the ecosystem. Without the unfeasible reintroduction of wolves to hold deer populations at a sustainable level, the deer eventually will succumb to disease and starvation unless humans intervene. Hunting as a means of population

control can be especially effective when localized populations are targeted. However, under most circumstances, a primary effect of such deer harvests, if only occurring for a short term basis) is an increase in the health of the surviving individuals (because of more resources available per deer) and an increased reproduction (more young per female). If hunting is the primary management tool, then usually it must be continued at least periodically in perpetuity at the regional scale, because total elimination of deer is seldom feasible or desirable. One reason that hunting has not stopped the continued deer population growth in the Connecticut, New Jersey, and New York area is that much deer habitat is highly intermingled with low-density residential areas, making many areas unsuitable for hunting despite the presence of many deer.

Wildlife management (cont.)

Eastern Coyote (Canis latrans)

Coyotes in the suburban areas of Westchester County act as a top predator in the food chain (after humans and vehicles) and help to thin deer herds by hunting weak and sick deer, as well as the young and old. Coyotes can be a threat to pets and frightening to humans who do not value the ecological niche coyotes fill.

People can discourage coyotes from visiting their property and coexist by following these NY DEC recommendations:

Do not feed coyotes. • If you see a coyote, be aggressive in your behavior - make loud • noises, wave your arms, throw sticks and stones. Do not allow pets to run free. • Do not feed pets outside. • Make garbage inaccessible to coyotes and other animals. • Eliminate availability of bird seed. Coyotes are attracted to the • concentration of birds and rodents that come to feeders. If you do feed birds, clean up waste seed and spillage. Fencing your yard may deter coyotes. The fence should be tight • to the ground, preferably extending six inches below ground level. Teach children to appreciate coyotes from a distance. • Ask your neighbors to follow these same steps. •

Deer Exclosures

An important tool for forest restoration, deer exclosures provide a refuge for regeneration by preventing deer browsing. The 8-foot-tall fencing allows the recovery of understory vegetation and tree seedlings that would normally be continuously browsed. Additionally, controlling invasive vegetation in the exclosure will further assist native plants to become established. Over time, the plant composition within the exclosure will differ from the surrounding forest and offer an opportunity to measure the effect deer and invasive species have on the ecosystem.

The Beaver Dam Sanctuary Mission Statement will be complemented by the use of deer exclosures by providing community use of the property “for scientific and educational purposes including ecological research and environmental studies.” Community collaboration can exist by providing each exclosure with a group of volunteers to regularly monitor the condition of the fence, control invasives, and note changes within the forest community.

Deer exclosures are generally about 30’ by 30’ and made of 8’ high mesh fencing. A stabilizing wire along the top of the fence is pulled tight between the posts to hold up the mesh, while metal stakes driven into the ground prevent animals from burrowing beneath. Posts are placed about 8’ apart and should be pounded into the ground until stable. Exclosures should be left in place until the plants have become established, and then the fencing can be moved to another area to start a forest restoration process.

Page 46: Beaver Dam Sanctuary Master Plan

Section 42

Page 47: Beaver Dam Sanctuary Master Plan

43Beaver Dam Sanctuary - Master Plan

APPENDIX

Page 48: Beaver Dam Sanctuary Master Plan

Section 44

Page 49: Beaver Dam Sanctuary Master Plan

45Beaver Dam Sanctuary - Master Plan

References

California State Parks and Recreationwww.foothill.net/fta/work/maintnotes.html

Carmel Mountain and Del Mar Mesa Preserves Management PlanTrail design & maintenance; February, 2002

Connwood Foresters, Inc.: Forest Stewardship Plan. Beaver Dam Sanctuary. Katonah, NY, 2005

Eastman, John: The Book of Forest and Thicket: Trees, Shrubs, and Wildflowers of Eastern North America. Stackpole Books; Mechanicsburg, 1992.

Gene W. Wood: Recreational Horse Trails in Rural and Wildland Areas. Design, Construction, and Maintenance; South Carolina, 2007.

Groves, Craig R. Drafting a Conservation Blueprint: A Practitioner’s Guide to Planning for Biodiversity. Island Press; Washington D.C., 2003.

Gutierrez, R.J, D.J. Decker, R.A. Howard, and J.P. Lassoie. “Managing Small Woodlands for Wildlife”. Cornell Cooperative Extension; Ithaca, 1990.

Herr, Beth: Beaver Dam Sanctuary, Natural Resource Management Plan; Katonah, NY, 2003.

Flink, Charles A., Kristine Olka and Robert M. Searns: Trails for the Twenty-first Century; Washington D.C., 2001.

Forest service technology & development program: Wetland trail design and Construction. www.thwa.dot.gov.

Knight, Richard L. and Peter Landres. Stewardship Across Boundaries. Island Press; Washington D.C., 1998.

Marsh, William. Landscape Planning. John Wiley and Sons; Hoboken, 2005.

New York State Department of Environmental Conservation (NY DEC) www.dec.ny.gov

New York City Department of Environmental Protection (NYC DEP)http://www.nyc.gov/html/dep/html/home/home.shtml

Randolph, John. Environmental Land Use Planning and Management. Island Press; Washington D.C., 2004.

Wessels, Tom. Reading the Forested Landscape: A Natural History of New England. The Countryman Press; Woodstock, 1997.

University of Minnesota: Recreational Trail Design and Construction. www.extension.umn.edu; June 2008.

Wildlife photos. www.flicker.com

Page 50: Beaver Dam Sanctuary Master Plan

Asiatic Bittersweet (Celastrus orbiculatus)

Common Reed(Phragmites australis)

Winged Euonymus (Euonymus alata)

Japanese Knotweed(Polygonum cuspidatum)

Invasive Vegetation

DESCRIPTION:A woody vine with yellow fruit that opens to reveal red berries, this deciduous perennial can climb up to 60’ high into trees and structures. The berries rip-en in September and the leaves turn yellow in the fall, making the plant easy to identify.

HABITAT:Bittersweet often dominates lowlands, especially along disturbed forest edges, fence rows, abandoned fields,

utility corridors, trail and roadways. This

highly invasive plant threatens native forests by strangling young trees, shading

understory veg-etation, and

weakening canopy trees, which makes

them susceptible to dam-age from ice and snow loads.

CONTROL:A high reproductive rate, long- range seed dispersal from birds, and root suckering make bittersweet difficult to control. Cutting and hand pulling is successful if care is taken to remove the roots. Annual inspections should be conducted to ensure new shoots have not grown from old roots.

DESCRIPTION:This perennial grass grows up to 5’ tall. Plumes are produced in July, yet can be seen throughout the year. In disturbed areas the plant can grow in dense spreading clusters that choke out native wetland vegetation and greatly reduce the value of the area as habitat.

HABITAT:Common reed is found in wet,

sunny areas without fast moving water.

The presence of this plant is

often a sign of enviro-nmental imbalance such as fluctuating

water levels, erosion,

dredging, sedimentation, and

pollution.

CONTROL:The plant spreads through seed dispersal and rhizomes. Stems that are knocked to the ground can produce new roots and stems. The first step for con-trol is to minimize any unnatural disturbances to the area. Yearly cuttings act to slow the spread of phragmites, but herbicide approved for use in wetlands is the most effective method of control.

DESCRIPTION:Commonly known as

burning bush, this ornamental shrub has been used extensively for years because of its bright red fall foliage and fruit,

and cork-like bark.

HABITAT:Euonymus is an invasive clump-forming bush that spreads to forests and pastures from surrounding yards where it was originally planted.

CONTROL: Besides spreading from adjacent yards, seed dispersal also occurs by birds that feed on the fleshy fruit. Young plants can effectively be hand pulled, especially when the soil is moist. In the case of mature plants and with dense thickets, either mechanical pulling or cutting and applying herbicide are the best methods.

DESCRIPTION: A fast-growing herbaceous perennial, Japanese knot-weed grows in large clumps with individual plants 3 to 6 feet tall. The hollow stems resemble bamboo, and the broad leaves have square bases and triangular tips. The light green leaves usually appear on the plant in April and greenish white flowers form in August and Septem-ber as the leaves turn red. Wind-dispersed seeds are produced several weeks later.

HABITAT:This plant prefers sunny, disturbed sites, especially along roadways and stream banks.

CONTROL:Once established, knotweed spreads primarily by rhizomatous roots, which can reach 45-60 feet long,

making the elimination of the plant difficult.

Control includes cutting the stems at least 4 times during the growing season and applying herbicide. Small colonies may be dug out, including the

entire root system. Establishment can be

prevented by removing plants when they are sighted.

Page 51: Beaver Dam Sanctuary Master Plan

Honeysuckle (Lonkera

Multiflora Rose(Rosa multiflora)

Garlic Mustard(Alliaria petiolata)

Japanese Barberry(Berberis thumbergii)

DESCRIPTION:Japanese barberry is a dense woody shrub, usually 2 to 6 feet high. The arching branches pro-duce rosettes of wedge-shaped, untoothed leaves. In May, small clusters of yellow flowers are followed by red oblong berries that stay on the plant into the winter.

HABITAT: Barberry aggressively takes over pastures, woodlands, and flood-plains with thorny thickets that prevent native herbaceous and shrub growth.

CONTROL: Young plants can be easily pulled out of the ground by hand, while a mechanical method must be used for mature plants. Gloves are recommended to avoid the thorny stems. Barberry is one of the first plants to leaf out in the spring, making this a preferred time to begin control, since it is

easy to distinguish it from other

woody shrubs.

Invasive Vegetation (cont.)

DESCRIPTION:A deciduous

shrub that grows 6 to 16 feet tall, hon-eysuckle has simple, op-posite leaves

that are oval to oblong. The

plant leafs out in the early spring and

remains green into No-vember. White or yellow flowers occur in May to June and berries are produced in July and August.

HABITAT: Honeysuckle tolerates a range of moisture levels and varying degrees of shade, yet prefers open areas with full sun.

CONTROL: The berries are food to many bird species, which then spread the seeds throughout the landscape. Once invaded, a site can become overtaken by the densely growing shrub that creates shade and depletes moisture and nutrients in the soil. Cutting the plant during the growing season in the early spring and again the following fall is the best method for controlling growth. Cutting during the winter encourages vigorous resprouting and should be avoided. Control must continue for 3 to 5 years.

DESCRIPTION:Branching directly from the ground, 9 to 12 foot long arching stems (canes) are covered in sharply toothed leaflets and thorns typical of roses. Clusters of white (or occasionally pink) flowers produce small red rose hips that are a winter food for

many bird and mammal species, which then

spread the seeds through the landscape. HABITAT: Multiflora rose

prefers sunny areas with well

draining soils, but is easily adaptable to

many conditions. In the past, multiflora rose was extensively planted as barriers along roadways and as living fences to contain livestock.

CONTROL:Cutting 3 to 6 times during the growing season for 2 to 4 years can be an effective to controlling this species. Areas that are lightly infested can be cleared with a shovel or hoe, as long as care is given to remove the entire root system.

DESCRIPTION:Biennial herb with alternating dark green, heart-shaped leaves. Small, white flowers with four petals are followed in the fall by oblong, black seed capsules. The leaves produce a garlic odor when crushed in the spring and early summer.

HABITAT:Moist, shady areas; especially in disturbed areas along roads, trails, and waterways.

CONTROL:Prolific seed production and a lack of natural predators allows garlic mustard to spread rapidly in infested areas. Hand

pulling or cutting the stems before

flowering is the best technique for control. The seed bank remains

viable in the soil for

2 to 5 years, so control must

continue through that period.

Page 52: Beaver Dam Sanctuary Master Plan

Weed Free Forage (cont.)

Page 53: Beaver Dam Sanctuary Master Plan

Weed Free Forage (cont.)

Page 54: Beaver Dam Sanctuary Master Plan
Page 55: Beaver Dam Sanctuary Master Plan

Prepared for the Beaver Dam Sanctuary Board of Trustees