Returning to the Nut Island:

 Restoring the Ecological Heritage to Governors Island

Jessica Leber

                                                                                                              
                                                                                   GIPEC 2006

 

 

                                     TABLE OF CONTENTS

 

1.0   Introduction……………………………….……………………………………….

2.0   Restoration Goals………………………………………..………………………... 

3.0   Historic Narrative…………………………………………………….…………… 

4.0   Current Context……………………………………………………………………

        4.1  Site Description……………………………………………………………….
        4.2  Planning Framework and Context………………………………………...…..

5.0   Tree Species for Restoration (Table 1)…………………………………………….

6.0   Phased Plan………………………………………………………………………...

       6.1 Phase I:  Seed source and Off-site Plantings……………………………………

       6.2 Phase II: Site demolition and soil preparation………………………………...

       6.3 Phase III: Planting Trees………………………………………………………

       6.4 Phase IV: Adaptive Management……………………………………………..

       6.5 Phase V: Restoring the Forest Ecosystem…………………………….......…..

       6.6 Phase VI: Long term management and future plans…………………………..

7.0 Public Participation and Use……………………………………………...............

8.0  Timing and Budget……………………………………………….........................

9.0 References…………………………………………………………………………

Figures
Figure 1: Current Site Layout and District Boundaries

Figure 2: Aerial View, Governors Island, Lower Manhattan, Brooklyn: 1876

 

1.0   Introduction

 

Governors Island is an urban planner’s dream: essentially a blank slate vacant island only one-quarter mile from the densest part of one of the world’s premier cities.  Its potential is limitless and the timing for redevelopment couldn’t be more perfect for New York City.  Our population is booming, economy growing, tourism increasing, and our real estate values bound effortlessly higher.  There is tangible excitement that we have the opportunity to create something special here; something that will make a substantive change to New York’s character.  Just the sense planners felt in 1853 when New York’s legislature designated a patch of land between 59^th Street and 110^th Street for a sorely needed urban park.  

 

Governors Island Preservation and Education Corporation, now weaving together a master plan for the island, has incorporated some admirable goals and does seek a unique vision.  The four conceptual development scenarios that characterize the range of density projections include: Minimum Build Island; Destination Island; Iconic Island; Innovation Island (GIPEC 2006).   Let us play a child’s game: which of the above four does not belong?

The Minimum Build scenario “illustrates the minimum investment scenario,” or a situation in which no new buildings are constructed, and a basic park and open space are created.  This option would “likely create the lowest level of activity and visitation on the Island, and therefore there would be little or no need to create additional access or transportation infrastructure to serve the needs of the Island adequately.” (GIPEC Minimum Build poster, 2006).  If that doesn’t qualify as a self-fulfilling prophecy, I’m not sure what does. 

 

Cut the qualifiers and the bureau-speak, add some flourishes, and this might have been said 113 years ago at the meeting that created Central Park.  A minimum build does not equate to a lack of vision nor does it consign the Island to a lonely life.  Governors Island’s most basic asset, other than its location - or rather because of its location- is its history. 

 

Here we have the singular opportunity to recreate a different and complementary history – one that long ago was wiped off the face metropolitan region.  This history goes back longer than the historic forts and longer than the cannons – it is the natural New York landscape.  A landscape that was distinctive in its own time and a celebration of what New York City is: an islands of diversity and places of linkages.

 

I say, to adopt the Minimum Build scenario, in fact requires the most daring degree of vision.  If we adopt this plan, one century down the road, our grandchildren will praise our foresight. 

 

 

 

2.0   Restoration Goals

 

The aim of this report is to describe and motivate the restoration of ecological heritage to Governors Island (the Island).  The reference year is1623, the year before Dutch settlers sailed into New York Harbor and landed on the Island.  The general goals are as follows:

 

• To restore a self-sustaining native hickory, oak and chestnut forest on the southern 90 acres of Governors Island, as it may have existed in 1623.

 

• To encourage a vital and diverse understory plant and faunal community that reflects the historic native diversity of the site.

 

• To restore the site to its original gently sloping topography and to raise the overall elevation to account for potential future sea level rise and minimize flood and erosion loss.

 

• To remove, once the forest is in place, much of the “man-made” coastline of bulkheads and piers and restore beaches and marshes to the shore.

 

• To integrate the restored ecological heritage of the South Island with the historic heritage of the North Island by creating an integrated educational, museum, science center, and research institution in the adaptive reuse historic district.

 

·       To encourage sustainable but significant public involvement and enjoyment of the forest, by paths, coastal walkways, beaches, and recreation.

 

The plan below incorporates specific steps needed to achieve these goals.  Throughout the text, the steps are justified and explained using a theoretical restoration ecology-based approach. 

 

3.0   Narrative of Ecological Heritage

 

In the middle of New York Harbor, 800 yards from Lower Manhattan and half this to Brooklyn, Governors Island was where the Dutch first landed in New York.  Then it was called Pagganck, or Nut Island, in the language of the Lenape tribe (GIPEC 2006).  The moniker fit because it described the nuts of the hickory, oak, and chestnut trees in abundance there (GIPEC 2006). The Lenape, the Native American of Mannahatta, would ford the narrow channel to gather them in season (GIPEC 2006).   They used the island seasonally for fishing and fur trapping as well (Request for Proposals, 2006). 

 

In 1624, two hundred settlers of the Dutch West India Company came into New York Harbor, and Governors Island was one of the first places they landed (Azoy 1951).  A Dutch governor purchased the land for a steal of two axe heads, a string of beads, and some nails in 1637; the name they only borrowed, calling it Nooten Eylandt (or Nutten Island) (GIPEC 2006). 

 

Dutch surveyors estimated the island’s size at 80 Dutch morgens, which is equivalent to about 160 acres (Azoy 1951).  The Dutch governor, Wounter Van Twiller, who envisioned an idyllic place to build a home, saw this: a sandy shoreline with a few rocks at the northern tip, a narrow sedge-filled creek separating the Island from Brooklyn that could be crossed at low tide, and a rolling surface that came to a high point at the northeast corner – a place for a commanding mansion (or as it later turned out, a fort) (Azoy 1951). 

 

Governors Island was one of the first sites where Europeans landed in New York - naturally, it was one of the first destroyed.  The first saw mill of the New World couldn’t have been sited at a better place – trees and wind power in abundance and water all around to float the logs (Azoy 1951).  Nutten Island was eventually stripped of most of its namesake; the name itself did not persist too much longer. 

 

The British took possession of Governors Island in 1664 and soon it began to realize it military potential.  Between the British and the Dutch, other uses over the years included grazing ground for goat, sheep and cattle grazing; a game preserve for English pheasants (the flock eventually overpopulated the Island and spread to Long Island); a tobacco plantation; and a quarantine for a ship of new arrivals with a plague (Azoy 1951).  The diseased were kept on the Island – eventually 250 died there, but the plague never spread to the mainland (Azoy 1951).  This highlights the benefit of the Island not only to contain diseases and invasive species; but to be isolated from these threats from the mainland as well. 

 

Centuries passed.  Without stabilizing tree roots, the Island shrunk, eroded by the tides (Azoy 1951).  In 1901, when a massive project to rebuild the Island was begun, it was only 70 acres in area.  If the original Dutch survey is correct, the Island shrunk by about 110 acres in about 275 years.  By 1901, a house built eleven years prior was sprayed by sea water whenever stormy weather hit. (Azoy 1951)  The Army Corps of Engineers addressed this by bulk and brute force - adding 103 acres of land to create South Island, more than doubling its size (GIPEC 2006).  Over 4.5 million cubic yards of soil and rock dredged from channels and excavated from the trenches of the city’s first subway line (the 4^th Avenue line) were dumped behind the extended 7,000-odd feet of bulkhead.  Even the fill is historic.  The estimated cost of reclaiming the submerged land was $10,000 per acre, and by 1912 the project was completed (Azoy 1951). 

 

4.0 Current Context

 

4.1  Site Description

 

Governors Island (“the Island”) consists of 172 acres of above water land and thirty two submerged acres (Figure 1).  The Northern Island contains the sixty two (of 225 buildings) on the Island that have historic designation status.   Of the “North Island,” twenty two acres is a National Monument, under the jurisdiction of the National Park Service, and the other 50 acres contains the historic buildings in the Governors Island Federal/City Historic District, under the control of Governors Island Preservation and Education Corporation (GIPEC).  Currently, the entire site is vacant and the Island is only publicly accessible by ferry, during limited hours over the summer.

 

The original seventy-acre Island, prior to the 1901-1912 Army Corps filling project, is now located on the North Island, while the southern 90-acres is built on fill.  The following topographic and subsurface data is based on a review of the Geotechnical Historic Data Report conducted by Langan Engineering and Environmental Consulting Services.  The elevation of the original land area, ranges from 9 to 40 feet above Governors Island Datum (referenced 1.7 feet above the National Geodetic Vertical Datum or 1929 mean sea level), while the elevation of the southern 100 filled acres is relatively flat, from 9 to 15 feet.  A wide swath of Island perimeter sits below the 100-year flood plain line (11.7 foot elevation), and a good majority of the Island’s area is below the 500 year flood plain.  

 

Within the historic shoreline, the immediate subsurface consists of 5 to 10 feet of historic fill; mainly sand, silt, and gravel and containing varying amounts of brick, wood, cinders and ash.  The fill is underlain by glacial till, weathered rock, then bedrock at a depth greater than 80 feet below surface grade.  Outside of the historic shoreline, the miscellaneous fill is as deep as 40 feet and contains obstructions such as metal, boulders, cobbles, and concrete.  The fill is underlain by organic silt and clay (this was once “off-shore”), glacial till, and finally bedrock at 115 feet below grade.  Groundwater is encountered at zero to six feet elevation (which varies on the site between three to 46 feet below surface grade) and is affected by tidal fluctuations. 

 

During site excavations, remnants of old building foundations, underground storage tanks, unexploded “ordnances,” (GIPEC Request for Proposal 2006) and subsurface contamination, including heavy metals, pesticides, polychlorinated biphenyls (PCBs), semivolatile organic compounds, and petroleum-related compounds associated with 250 years of military and artillery usage on the site may be encountered.   Also, typical urban fill containing ash and other debris is likely to contain elevated levels of semivolatile organic compounds (SVOCs), including polycylic aromatic hydrocarbons (PAHs) and metals.     

 

4.2 Planning Framework and Context

 

In 2003, after the U.S. Coast Guard vacated, the federal government sold Governors Island back to New York State for the price of $1.00, with the exception of the 22-acre historic monument district.  New York State, under the auspices of the Empire State Development Corporation, created Governors Island Preservation and Education Corporation (GIPEC), a public state corporation charged with planning, redeveloping and operating the remaining 150-acres of the Island.  The Board of Directors is appointed equally by the governor and the mayor.  GIPEC seeks to make Governors Island a “destination with great public open space and heritage tourism attractions, as well as education, conference, and cultural facilities.”  (GIPEC 2006)

 

GIPEC intends to maintain ownership of the Island and extend long-term leases to the developers of the site.  GIPEC will be responsible for overall Island infrastructure and utilities.  Its stated goal is to create a suite of Island uses that will financially sustain the Island to eventually earn money.  This would only be accomplished by an increase in public usage of the Island (GIPEC Request for Proposals, 2006). 

 

Currently, GIPEC is reviewing proposals for preservation and redevelopment of the Island.  The proposals requested were to be highly developed plans from qualified parties, but the range of possibilities has not yet been constrained.  Proposals could stretch from a single building to a master plan for the entire 150-acre site.   In early 2008, GIPEC expects to affirm a final General Project Plan, at which point environmental review under the State Environmental Quality Review act guidelines will begin.  Public input will be sought throughout this process, as is part of GIPEC’s goals and is mandated by law. 

 

5.0  Tree Species for Restoration

 

The first goal to be implemented will be to restore the oak-hickory-chestnut forest to the Island.  Although there is no exact record of the species present in the reference year of 1623, it is easy to surmise the suite of native oaks, hickories, and chestnuts whose range extends into New York City that were like present in the past. 

 

Among the large selection of native oak and hickory species, the ones chosen for the restoration were selected based on predicted ecophysiological and genetic adaptation to the conditions of the site (ie: their likeliehood of long term success and recruitment).   Table 1 describes the characteristics and limitations of restoring each chosen species of tree.  Also, to the extent it is feasible, the native trees, including oak, sycamore, and maple, already existing on the site during the demolition and soil treatment phase should be preserved (Dunlap 1995).

 

In New York City, due to the urban heat island effect, average temperatures (and especially nighttime low temperatures) are several degrees warmer than the surrounding rural region (Leber unpublished, 2006).   In addition, in light of global warming, the climate of the New York region will continue to warm significantly over the next centuries.  Since the restoration of the forest takes time, fortitude and foresight, centuries is not an inappropriate timescale to plan for.  Therefore, all trees below were chosen because their range extends significantly further south of the New York, and therefore, these trees will be tolerant of the warmer temperatures, both now and in the future, that they will be exposed to.

 

To encourage a range of genetic diversity that will be necessary to avoid long term inbreeding depression on an Island, it will be required that several different seed sources are used for each species.  These should be a mix of local source for specific local/urban adaptations, and regional seed sources to provide flexibly adapted plants tolerant of a wide range of conditions.  In Table 1, several local seed sources are proposed for each species.  In addition, regional native plant nurseries should be utilized as seed sources. 

 

Table 1: Proposed Trees Species for Restoration to Govenors Island

Sources: (Glenn 2006; Moore 2006; Barnard 2002; Burns 1990)

 

Tree	Benefits	Potential locations on-site	Planting considerations
Shagbark Hickory (Carya ovata)	Prodigious  nut producers; highly edible nuts (food for wildlife); tough resilient wood can withstand stress; tolerates wide range of soil conditions	Can be distributed throughout the Island;	Local seed sources: Pelham Bay Park, Prospect Park, Brooklyn Botanical Garden.    Average 10 year height (Ohio Valley) = 7 feet (slow grower), do not plant directly adjacent to fastest growing trees
Bitternut Hickory (Carya cordiformis)	Most abundant of hickories; Least edible nut –nuts are more likely to survive to germination because herbivores don’t like them.  Grown fast for a hickory and grows well on poor soils low in nutrients.	Usually found on wet bottom lands, but grows on dry sites – plant on topographic lows or coast for less drained soil.	Local seed sources:  NY Botanic Gardens; Pelham Bay Park; Prospect Park; Inwood Hill Park   10 year height (Ohio valley) = 10 feet; also relatively slow grower; Mature height 60-80 feet.
Pignut Hickory (Carya glabra)	Fallen nuts are too sour for people, hogs used to eat them (hence name).  Tough, able to survive in poor soils and dry locations; Resilient hearty wood – the heaviest of hickories; A soil “improver” because leaves have high Ca content;	Seedlings survive in deep shade, allowing tree to root in forests alongside oaks; Plant alongside oaks and other fast growers.	Local seed sources: Pelham Bay Park; Brooklyn Botanic Gardens, Prospect Park, Central Park, Inwood Hill Park; Staten Island Greenbelt   5 year height (Ohio valley) = 9 feet;  50-60 feet mature height
Scarlet Oak (Quercus coccinea)	Fairly fast grower; Bitter kernal acorns. widely planted as an ornamental. Its brilliant red autumn color, open crown texture, and rapid growth make it a desirable tree for yard, street, and park.	Frequently found on gravelly or sand soils near shore; Occurs alongside stands of post oaks, white oaks, and other broadleaf trees.   Very intolerant of shade – must plant near slow growing trees or give seedlings more space to grow.	Local seed source:  Prospect park, Central Park, Riverside Park, Connetquot River State Preserve (Long Island).   Roots grow close to the surface (can plant near deeper rooting trees for a range of soil use).
Northern red oak (Quercus rubra)	Faster growing than any other oak; withstands pollution well.	Grows well on slopes and well drained soils.   Do not plant next to shade sensitive oaks due to fast growth	Can become water stressed during drought.
Post Oak (Quercus stellata)	Tough tree grows where many do not – poor, dry, gravelly or rocky soil on sandy plains; Tolerates heat and drought and higher salinity of coastal habitats.	Intolerant of shade and slow growth rate compared to most other oaks.     Plant near hickories and other slow growers.	New York coastal region is the northern extent of habitat.  Found in: Pelham Bay Park, Central Park, Bloomingdale Woods (SI), Caumsett State Park near beach (LI), Sands Point Preserve on bluffs overlooking LI Sound
Pin Oak (Quercus palustris)	Among most widely planted native oak in urban landscape and third most common street tree in NYC; able to withstand occasional flooding and low O2 levels found in urban soils; tolerates drought and easy to plant due to shallow roots	Can be planted throughout island, but especially along shoreline.   Shade intolerant; lightly spaced plantings	Local seed sources: Willamsbridge Oval, Saint Nicholas Park (Bronx), Central Park West, Forest Park (Queens)   Short-lived species, reaches maturity in 80-100 years.
American Chestnut (Castanea dentate)	Once the most valuable of native trees, this species has been essentially eradicated in the United states when a fungal disease was brought to NY from Asia in 1904.  By 1930, most chestnuts in this country were dead.  Some chestnuts remain, however in New York City.  Main benefit to restoration is 1) Historic and nostalgic potential; 2) Opportunity to experiment with way to successfully restore the American Chestnut	Consult experts in American chestnut restoration for best planting methods and location.    Individual trees should be spaced far apart (>50 m) to ensure the disease is not easily spread if one is infected.  Will need monitoring.	Local seed sources: Van Cortlandt Park, Brooklyn Botanic Garden, Forest Park (Q), High Rock Park (SI) west of Loosestrife Swamp, Totten Hill.*  Priority here is to obtain seeds from only healthy trees, rather than to use local sources.     If pure American chestnut restoration is not successful, would consider using the experimental Chinese chestnut/American chestnut hybrid; which has enhanced immunity to disease.

 

6.0 Phased Plan

 

6.1 Phase I: Seed source and off-site plantings

 

The conditions of a barren site fully stripped of buildings and pavement will be extremely harsh for the developing seedlings.  Therefore, it is desirable to collect plant sources and plant in a nursery so that seedlings can develop as much as possible before it is time to transplant them at the site.   Ideally, the trees will be at least two years old before being transplanted to the site; perhaps older given advance planning and time. 

 

As mentioned above, an effort should be made to obtain seeds from a wide range of populations so that genetic diversity is encouraged and inbreeding depression is avoided.  Trees were chosen mainly for their adaptability and suitability to urban conditions; therefore, outbreeding depression is less of a concern because it is known they will be physiologically tolerant of harsh on-site conditions. 

 

Appropriate procedures for transplanting individual species should be implemented.  A seed propagation program specifically designed for the Governors Island should be set up begun once the initial cohorts are planted at the nursery to provide a continual source of seeds and plant material that will be necessary in first stages of the program before trees begin to produce nuts. 

 

6.2 Phase II: Site demolition and soil preparation

 

All buildings on the southern 90 acres will be demolition and all site paving will be stripped.  During the time of site preparation and demolition, stormwater management and erosion controls should be implemented, both on the shore to prevent runoff into New York Harbor and on areas of the site where earth is not actively being moved. 

 

This soil treatment phase of the project will be especially important.  The natural biogeochemical cycle of the site has been for years shut down, as it has been covered with pavement, eroded, and literally recreated from nothing.  Therefore, a large component of the project’s cost will be in restoring the abiotic and biotic cycling regimes that are vital to a forest ecosystem. 

 

Soil Remediation:

As mentioned above, fill is present on the South island (outside of the historic shoreline) to a depth of 40 feet below grade, and is likely to contain contaminants, both related to the presence of historic ash-containing fill and to former site military uses.   Of the species presented in Table 1, some are “street” trees in New York and are likely to some extent tolerant of the presence of fill; however, soil of such degraded quality is not suitable for restoring an entire forest.

 

Removing the fill is not feasible due to its depth and spatial extent.  Phytoremediation is not feasible because it is a slow process, and cannot cover the entire soil matrix through which contaminants are dispersed.  Furthermore, it is only appropriate to heavy metal contamination (whereas other contaminants will exist at the site).  Therefore, I propose to cap the fill with at least 5 feet of clean top soil that will be appropriate for plant growth.   This will serve the multiple purpose of acting as a buffer between the fill, providing suitable soil for tree growth, and raising the overall site elevation (see below). 

 

Site Grading

Two considerations are important for grading: raising the entire coastal elevation of the site to one foot above the current 100-year flood plain at 11.7 feet above Governors Island Datum and restoring topographic heterogeneity to the Island.  Currently, most of the shore sits below this level.  In future global warming scenarios, New York Harbor will be affected by sea level rise in the coming century.   Any investment in such a long term project as Governors Island requires planning for these future changes.  Likely, the elevation of the 100 year flood plain will increase in the future, so a buffer of 1 foot above the current flood plain line seems like a good investment.

 

The Island once had rolling hills, and we would like to restore this historic landscape.  Hills provide additional benefits to the trees being planted, because they will provide a gradient of well drained and flooded soils.  The wide diversity of trees being restored will thrive in the heterogeneous topography.  For example, Pin Oak thrives in flooded soils while Post Oak thrives under dry gravelly conditions (although both are fairly flexible).  Sets of small hills should be restored on a small scale and on the macroscale of the Island, the center of the Forest should be at a topographic high compared with the coast, to create an overall site drainage gradient.  However, soil erosion control should be considered when planning the grading of the site, and slopes greater than 33% should be avoided (Sauer 1998).

 

Soil Amendment

 

For disturbed sites, standard soil specifications call for routine topsoil stripping, fertilizing, and liming (even though many disturbed or made soils are already less acidic than native because of concrete rubble and urban dust) (Sauer 1998). In general, soil ecosystems have a great deal of redundancy and a full soil structure is usually not required for most basic soil functions (Sauer 1998).  It will take a long time to develop a full soil microbial community at the site, but the basic functions will be sufficient until that time. 

 

The goal of a soil restoration needs to enhance bacteria, fungi, and microfaunal communities.  Most of work in forming humus is done by plant roots and by animal life in soil.  Ecosystem function of soil is to cycle energy and nutrients – nitrogen, sulfur, and phosphorus – through the system and also to increase water holding capacity. The soil microbial community also contributes to soil stability (Sauer 1998). Fungi tend to dominate in forest soils, whereas bacteria dominate in agricultural soils.  Roots of grasses also exude carbon and amino acids directly into the soil to feed fungal associations – it may be beneficial to allow some native grasses to develop on the cleared site initially to help restore soil functionality (Sauer 1998). 

 

The reason fungi dominate in a woodland is because only fungi can break down lignin in wood.  Simply covering the soil with raw wood chips provides an ideal matrix for rapid development of dense fungal networks and provides surface stabilization.  The benefit of using woodchips over commercial fungal inoculums is that it encourages the development of native local soil biota (Sauer 1998).  In addition, the top soil can be inoculated as necessary with mychorrhizal fungi associations.  Organic matter will also need to be added to soil – this can be done through using a local source of compost, such as the composting facility located in Central Park. 

 

Lastly the soil pH should be monitored and the soil fertilized with nutrients, like nitrogen, phosphorus, and sulfur as necessary.  With concrete rubble and dust present from the remnants of demolition, it’s entirely possible for the soil to become extremely basic.  If possible, atmospheric fluxes and approximate dry deposition rates of nitrogen and sulfur should be monitored to understand the “natural” inputs to the system.  Because it is an Island with a singular use, there will be few other nutrient inputs to the soil at first without human intervention. 

 

6.3 Phase III: Planting

 

Using the transplants grown off-site as the primary source of plant material, trees should be planted according to the considerations outlined in Table 1.  In general, prior to the planting phase, a specific tree density criteria should be established, based on: the rooting depth and breadth of each species, the rate of growth and tolerance of light and shade, and the relative position of each tree.   On a larger scope, the soil drainage patterns and tolerance of trees to flooding and coastal environments (including sea salt) should be specifically considered when deciding where to plant which trees.   Tree seedlings, such as Quercus rubra, which are sensitive to dry conditions, should be actively watered during dry periods.  In addition, if species are sensitive to too much light, or heat (the microclimate at the soil surface will become very hot after clearing of the site), then structures can be built around specifically sensitive seedlings to shade them. 

 

Planting in loose clumps or gaps, a technique called nucleation, is preferable to planting in rows (Sauer 1998).  As an average (all this may vary significantly by species), seedling spaced as close as three feet apart and as far as 8 feet apart do well (Sauer 1998).  The mortality rate of plantings on restoration sites, especially on degraded sites, is especially high.  Many more seedlings than are expected to survive should be planted (perhaps more than double the number), so that the restoration is not set back when a large percentage do not survive.  In addition, this extra competition may help ensure that the best adapted, most fit and phenotypically plastic seedlings are the ones that survive to further reproduce. 

 

6.4 Phase IV: Adaptive Management

 

Active management of the nascent trees will be necessary for many years, as this plan is meant to be a preliminary guide.  The first phase of adaptive management will focus on monitoring the health of the growing trees, seeing that erosion is controlled, and ensuring that the soil, light, nutrient, and water conditions are suitable for tree growth.  It may be necessary to actively water, shade, or enrich the soil until the natural biogeochemical cycling ecosystem function emerges from the system.  

 

It is quite possible that some of the species suggested here will fail to establish, and others will do quite well.  Since Governors Island will be acting as a preserve of native biodiversity, a large diversity of trees native to the Island should be present, but the suite of trees should be altered from those listed here as necessary.  The management strategy should be reevaluated regularly to ensure that the management plan evolves along with the ecosystem and that the right decisions are made in its implementation.  

 

Since this restoration of a forest is skipping primary and secondary successional processes, there will be a natural tendency after the site is cleared for grasses, shrubs, weeds and invasive species to establish themselves on the site.  Some grasses may be allowed, especially if they contribute to soil nutrients, but any competition of seedlings with weeds, and especially invasive species, needs to be avoided.  A monitoring program to prevent the establishment of weed should be established. 

 

Often the theory of island biogeography is applied metaphorically to describe patches of perhaps fragmented landscape.  Here, on Governors Island, the Island nearly completely isolated from the mainland population, and is also isolated from the two nearest large islands (Long Island and Manhattan) with no land connections.  Normally, isolation of a population is seen as a difficulty because it may cause local extirpation of a species on the island and a lack of recolonization (or “rescue effect”) from the mainland source.  However, in this managed and urban setting, the risks of invasive species and diseases to the Island may far outweigh the benefits of landscape connectivity (especially because, Island restoration managers will artificially rescue any species that are in trouble and actively seek to maintain genetic population diversity).   Therefore, the Island’s isolation should be viewed as a key advantage to restoration in this setting. 

 

The only connections to the mainland, then, are the risks of invasive seeds or diseases transported by wind and birds, or by humans who come over on the ferry.  The risk of wind-born seeds is relatively low, given that there are likely extremely few seeds to transport in the immediate highly developed area of Lower Manhattan and Downtown Brooklyn.  Since human access to the Island will be controlled by boat, an education program for awareness of invasive species should begin on during the travel of visitors’ to the Island, so that they know what to watch for and what to avoid bringing to the Island.  This combined with a proactive invasive species early removal program should be highly effective in keeping the Island for native trees and plants. 

 

6.5 Phase V: Restoring the Forest Ecosystem

 

The first four phases of restoration have focused on establishing trees.  However, once a first cohort of health seedlings are established, it is possible to begin restoring the understory community for the forest as well as a faunal community.  The understory should be established to include native shrubs and herbaceous flowering and non-flowering plants, such as grasses, sedges, rushes, ferns, and mosses (Sauer 1998).   In addition a leaf and organic matter litter layer should be allowed to develop.  When a litter layer accumulates and persists, it acts as a nursery for the next generation of forest and creates a thick humus (organic soil horizon) to build topsoil (Sauer 1998).   Woody debris should also be left, as it can serve as another source of small-scale heterogeneity where a diversity of flora and fauna can grow, and it will eventually decompose to further enrich the soil (Sauer 1998).  

 

Many restoration ecologists will take the “if we plant it, they will come” approach to restoring faunal communities, once the flora ecosystem is established.  This is more of a problem on an island, where for some species, purposeful introductions should occur.  No purposeful introduction of significant herbivore populations should occur until the forest is well established.  The bottom-up approach to ecosystem control is a key component of restoring this forest.  If herbivores populations become too high too quickly, especially because there will be few to no predators, then the system risks becoming flipped and a top-down control will limit or perhaps destroy the success of the growing forest.  Therefore, limited and carefully applied use of non-toxic pesticides could be warranted if this were the case. 

 

The timing of the development of the faunal community should be approximately timed to shortly after many of the trees have begun producing seeds.  Insects and small mammals will the aid in the dispersal of seeds and pollination of the understory flowers. Ensuring that the trees do produce fruit and that they are dispersed throughout the island by a health faunal community is important to the long-term sustainability of this forested ecosystem.

 

Lastly, it will be eventually important to introduce some native predators to the Island and make it an attraction to migrating birds and marine life as well.  This will help keep growing herbivore populations under control.  These last steps of introductions will be the result of creating a healthy functioning ecosystem at the base.

 

6.6 Phase VI: Long term management and goals for the future

 

Ensuring the reproduction, germination and recruitment of seeds and new trees will be important for sustaining the forest in the long term.  Continued management will likely always be necessary, but there is a difference between management and futile effort.  The long term management will be to monitor the reproductive health of the growing trees and encourage new trees to establish naturally, rather than through direct seeding or transplanting. 

 

In addition, long term thinking could involve the restoration of the other native ecosystems of the Island, including salt marshes (British Headquarter Map 1782) and the sandy beaches of the shore (Azoy 1951).   Ultimately, once the forest has been reestablished, a major biodiversity ecosystem function will be to control the erosion of the Island.  At this point, the man-made coastline that includes retaining walls, bulkheads and piers can be removed in favor of reestablishing the rocky and sandy shorelines and salt marsh community. 

 

7.0 Public Access

 

Access to the forest restoration will by necessity need to be limited for a few years, in order for the delicate plantings to establish themselves.  Pathways, however, should be cut through the forest so that the public can enjoy the benefits of learning first hand about the ecological heritage of the Island, New York City, and the Northeast.  There will need to be some limitations to how densely the pathways should be used and a massive education program (beginning on the transportation over to the Island) to ensure the public is aware of how to enjoy the forest, while doing no harm.  In addition, a natural pathway bordering the forest should encircle the Island with the amazing views in all directions.  

 

The most important link between the North (historic) and South (ecological) Islands will be in the middle-ground adaptive reuse historic district.  These historic buildings and grounds should be reused to create a vital education program for the public.  This should not only involve the traditional modes of ecological education, such as nature centers and natural history displays.  There should be a center for engaging talks, discussions; a center for the arts; a place to screen movies and hear music; and a place to learn about our Native American, Dutch, British, and American historic heritage.  While looking back at the past, however, a strong emphasis needs to be placed on education about the future, including the ecological future of Governors Island and New York. 

 

Throughout this education there should be a strong underpinning of real science learned.  A research center for scientists who will perform studies in restoration ecology and other fields on Governors Island should be established, and a portion could be made accessible to the public.  

 

The transportation to the Island should still be by ferry only, so that the benefits of the Islands isolation are maintained and access is through a controlled entry and exit point.  However, it is necessary to massively expand the number of ferries that run and the locations they stop at.  Right now, the ferries only depart from Lower Manhattan.  In the future they should depart from various points from Staten Island, Manhattan and Brooklyn, and ferries should link the Statue of Liberty (symbol of freedom), Ellis Island (symbol of diversity), and Governors Island (symbol of heritage), and the memorial that will be built on the World Trade Center site (symbol of resiliency).

 

A last unique transportation alternative that has already been proposed is creating a system of cable cars that transport between Manhattan and Governors Island.  This would be a unique transportation system that adds value and character to the site, and a good supplement to the ferries, while still maintaining controlled access. 

 

8.0 Timing and Budget

 

This is a conceptual timeline and budget for the 90 acres of forest restoration and forest management on the South Island.  This does not include transportation infrastructure, the public use structures proposed in the historic reuse district, the costs (and labor) involved in maintaining public access to the forest, nor other future restoration plans.  GIPEC is supposed to pay to install the utilities and general infrastructure to the Island (GIPEC Request for Proposal 2006).  Since a minimum of utilities will be necessary, this budget should initial go toward funding the first phase of the project.  During this time, a foundation should be established, with significant fundraising drives in conjunction with the historic portions of the site, to continually fund this restoration.  Large individual contributions should be solicited.   It is likely that additional city, state, and federal funding and in-kind donations could be obtained.   

 

 

 

Phase I:  Seed source and Off-site Plantings

Costs: Seeds, Nursery, and 4 full-time decision-making employees and additional labor staff (can use summer interns)

Budget: $1 million per year

Time: 2-3 years (to coincide with planning efforts)

 

Phase II: Site demolition and soil preparation

Costs: Demolish up to 180 buildings and foundations; Soil quality investigation and remediation; Water drainage and erosion study; Topsoil (5 feet over 90 acres); Construction equipment; Grading; Heavy Union Labor

Budget: $100 million (Most of this cost is being spent on Governors Island no matter what development path is taken)**

Time: 2 years

 

Phase III: Planting Trees

Costs: Significant Labor (not volunteer), planting and heavy equipment; fertilizers; shading structures; surveyors; Establish permanent offices on Governors Island

Budget: $2 million (for initial set of plantings and offices)

Time: 6 months

 

Phase IV: Adaptive Management

Costs: 10 full time employees, and part time and summer work.  Equipment for watering and fertilizing and planting.  Permanent offices on Governors Island. 

Budget: $1.5 Operations and Maintenance Budget/year

Time: 10 years

 

Phase V: Restoring the Forest Ecosystem

Costs: Additional studies; Procuring seedlings for understory, as well as a faunal community; Additional seasonal and part time labor for planting and animal counts

Budget: $600,000/year of two years (after this, this segment of project is folded into either adaptive management phase or long-term management phase)

Time: 2 years (floating on timeline- can begin during adaptive management phase or long term management phase)

 

Phase VI: Long term management

Costs: 5 full time employees; equipment operations and maintenance costs

Budget: $600,00/year

Time: Indefinite

 

 

 

 

 

 

9.0 References

 

Azoy, A. C. M. (Anastasio Carlos Mariano). Three Centuries Under Three Flags : The Story of Governors Island From 1637. Governors Island, N.Y. : Headquarters First Army, 1951.

 

Barnard, Edward Sibley. New York City Trees, A Field Guide for the Metropolitan Area.  Columbia University Press: New York, New York, 2002.

 

British Headquarter Map: 1782.  Available from Dr. Eric Sanderson, Wildlife Conservation Society: Mannahatta project (Publication in progress).  

 

Burns, RM and Honkala BH.   Silvics of North America: Volume 2 (Handbook 654).  USDA Forest Service: Revised December 1990.

 

Dunlap, David W.  Islands Lapped by Tides of Change.  The New York Times: November 12, 1995. 

 

Glenn, Steven D.  The New York Metropolitan Flora Database, Genus: Quercus.  Brooklyn Botanic Gardens: Revised June 2006.  Accessed October 11, 2006. 

 

Glenn Steven D. The New York Metropolitan Flora Database,  Genus: Carya.  Brooklyn Botanic Gardens: Revised September 2006.  Accessed on October 18, 2006. 

 

Governors Island Planning and Education Corporation (GIPEC).  On-line resources available at: http://www.govisland.com/.  Accessed on December 4, 2006.

 

Governors Island Planning and Education Corporation (GIPEC). Request for Proposals for the Preservation and Redevelopment of Governors Island.  February 15, 2006. 

 

Langan Engineering and Environmental Consulting Services. Geotechnical Historic Data Report, Governors Island Development, New York, NY: February 2006. 

 

Leber, Jessica. Unpublished. The Reproductive Output and Growth of Xanthium strumarium L. along an Urban to Rural Gradient.  Course term paper: Plant ecophysiology: December 5, 2006.

 

Moore, Gerry.  The New York Metropolitan Flora Database,  Genus: Castanea.  Brooklyn Botanic Gardens: Revised June 2006.  Accessed October 18, 2006. 

 

Sauer, Leslie Jones and Andropogon Assoicates.  The Once and Future Forest: A guide to forest restoration strategies.  Washington D.C.: The Island Press, 1998.

 

 Figure 1: Current Site Layout and District Boundaries (Source: GIPEC website, 2006)

 

 
 
 
 
Figure 2: Aerial View, Governors Island, Lower Manhattan, Brooklyn: 1876.  Governors Island on right.  (Source: GIPEC website, 2006)