Restoring New York City
Proposals for Improving Ecological and Human Health
Edited by Dr. James A. Danoff-Burg
Department of Ecology, Evolution, and Environmental Biology, Columbia University


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Inwood Hill Forest Restoration

Tanja Crk


Contents:

 

I.                    Abstract
II.                 Historical background of land and species composition information
III.               Theory and considerations
IV.              Current Problems
V.                 Plan for restoration and its benefits
VI.              Timeline, budget, amount of work needed for restoration plan
 

 

I.                    Abstract

 

The restoration plan proposed herein will focus on the central forest of Inwood Hill Park, Manhattan, New York City. The attempt is to limit fragmentation caused by excessive path creation and usage, erosion on slopes caused by reduced groundcover that is exacerbated by the paths and invasive species, and, finally, the invasive species themselves. The budget for this 8-year project is an estimated $206,000 and will require many hours of volunteer assistance each season (Spring and Fall). The project will require removal of paths that may be currently used, though relatively infrequently. In order to compensate the neighboring communities, the building of two watchtowers for scenic bird-watching and the publishing of a self-guided tour designed for the already heavily utilized paths will accompany the restoration effort.

 

II.                 Historical Background of land and species composition information

 

Northern Manhattan parks restoration projects have taken a bottom up approach, structuring a community from the primary producers on up through the food web. The goal of this ecosystem-level restoration project is to focus on the same. According to the NYC Department of Parks and Recreation website, the restoration team has been successfully restoring forest by removing non-native plant species and replacing them with native trees and shrubs. By 2000 the team completely restored 2.5 acres of forest in this manner, planting 5,130 native trees and plants to replace the removed non-natives and 4,686 native wildflowers and grasses to keep soil by the Hudson River from eroding (nycgovparks website). Of the three project sites under restoration (Inwood Park, Fort Tryon Park, and Riverside Park) in Manhattan, Inwood Park is of particular interest. 

After going through many phases in its history, Inwood Park is established as a park in 1916 (Inwood Hill Park Nature Center), but officially opens on May 8, 1926 (Renner 2003). The park was a home to the Wiechquaesgeck (or Lenape) Indians, who made their village in the central valley, ‘Shorakapkok Glen,’ with Shorakapkok meaning ‘edge of river’ (Loeb 1986, Renner 2003). Presumably, they sold the entire island of Manhattan to the Dutch for $24 on November 5, 1626 next to a tulip tree on a knoll by Spuyten Duyvil Creek (Renner 2003). Around 1900, the village was excavated for archaeological artifacts (Loeb 1986). The Native Americans utilized the caves of the moraine for shelter, fished the waters, and hunted deer, raccoon, and bear; they inhabited the park area until the 1930’s (Renner 2003).

During the American Revolution, the vegetation of Inwood Park was entirely cleared (Loeb 1986) but at the time Inwood was known as Cox Hill (Bresham 1990). During the 19th Century, after 1830, the park land was sold to and used by wealthy New Yorkers to build their retreat and country homes; those included are: Isidor Straus, the Bolton family, and the Lords of Lord &Taylor (Loeb 1986, Renner 2003). Those that owned farm animals had to protect them from wolves, foxes, and wildcats (Renner 2003). Because of their actions these top predators no longer inhabit the area and this has been the case since the 1890’s (Renner 2003). Even after extirpation of top predators, deer, and bear species, the park presumably still hosts an array of bird and terrestrial animal species (see Appendix B), which would potentially benefit from the proposed restoration project.

In addition to residential development, the New York and Hudson River Railroad opened in 1847, but is no longer in use (Renner 2003). In the late 1920’s, the rich abandoned their homes; the roads leading to them were closed and the homes were removed (Bresham 1990). Remnants of old residential and public infrastructure can still be seen and some are in use, though not for their initial intended purpose. For example, the Jewish Memorial Hospital, which was once in the park, is now a school building; and, what used to be a boathouse is now the Inwood Hill Nature Center (Renner 2003).

 In addition to anthropogenic disturbances, natural disasters have hit New England in the past. For example, a massive hurricane hit the area in 1938, destroying trees and eroding soil (Loeb 1986), presumably killing the historic tulip tree at the site of the famous land acquisition (Inwood Park plaque). Fox species were present in the park until 1900 and the raccoon population plummeted to near extinction at the creation and subsequent fragmentation of the park by the Henry Hudson Parkway (HHP) in 1937 (Wikipedia 2006). The raccoons once built nests where the HHP was built and had to cross it once it was built to reach the Hudson River for food (Bresham 1990). Therefore, not only did they lose their nesting ground, but the raccoons were killed by crossing the parkway.

In the 1930’s the WPA (presumably the Works Progress Administration) created ‘nature walks’ in the park and in the 1960’s the Parks Commissioner, August Heckscher, installed iron lamps along the paths and some remain today to stand as ‘accent ruins’ along the old trails (Bresham 1990). Some parts of the park were not originally at the site such as the land extension into the Hudson River in the northwest and the lagoon to the east, built from 1930 to 1942, as well as, riprap installed and other erosion control measures performed from the mid 1970’s to 1985 (Loeb 1986). The city acquired land in 1924 (lawn site), 1936 (land under Spuyten Duyvil Creek), and 1941 (land under the Boat Basin) (Bresham 1990). Based on the natural disturbance history of the land, we see that we are dealing with a relatively young and immature forest (Loeb 1986).

Inwood Park is said to be ‘the last natural forest and salt marsh in Manhattan,’ an 196.4 acre (79.4ha) oak-tulip tree forest (“Inwood Hill Park”, Loeb 1986). However, due to all the land use changes, where the ground has never been left completely alone since its habitation by humans, Inwood Park is perhaps better described as having a “naturally derived plant community” (Loeb 1986). In 1974, one researcher counted 250 plant species in the area (Loeb 1986). Among all the plant species present, more than 80% of the forest is composed of trees more than 5m high and, primarily, the Tulip tree (Liriodendron tulipifera) which can reach heights greater than 50m and which is co-dominant with four species of Oak trees including white oak (Quercus alba, 30m), chestnut oak (Quercus montana, 20-30m), red oak (Quercus rubra, 35m), and black oak (Quercus velutina, 20-25m) (Wikipedia, New York Natural Heritage Program 2006). Among the characteristic tree species which also includes red and sugar maple, sweet birch, American beech, and white ash, there is an assortment of shrubs of varying sizes, herbs, and a small number of vines, mosses, and lichens (New York Natural Heritage Program 2006). According to Loeb (1986), the park is actually composed of four ‘plant communities’: the forest, successional field, salt marsh, and lawn; and, seven ‘vegetation types’ including: valley forest, salt marsh (at six different locations), slope forest, north-facing forest, successional forest, successional field, and lawn. (Refer to Fig.1 taken from Loeb 1986).  Other names synonymous with oak-tulip tree forest include: mixed hardwood forest (Elliott 1994); primeval forest (Busing 1995); temperate deciduous forest (Busing 1995); eastern deciduous forest (Busing 1995, Inglesby 1958); eastern mixed hardwood (Lefkowitz 1973); mixed mesophytic (Lefkowitz 1973); oak community (Lefkowitz 1973); red oak forest (Lefkowitz (1973); red oak-tulip tree-dogwood community (Lefkowitz); hardwood-hemlock forest (Rudnicky 1989).

 

Figure 1. Inwood Hill Park according to Loeb 1986.

 

 

The Typa and Spartina communities were destroyed in the lagoon area since the 1930’s and early 1940’s (Loeb 1986). In general, the salt marshes receive lots of human induced disturbances (Loeb 1986) and restoration projects in the past have been both successes and failures. For example, Chenopodium rubrum  and Xanthium echinatum seed transplantations to marsh 1, and Myrica pensylvanica and Asclepias incarnate to marshes 3-4 from a source location in Pelham Bay Park worked. However, similar transplantations of Limonium carolinianum and Suaeda maritima to marsh 3 did not work (Loeb 1986). Unfortunately, salt marsh restoration will not be considered in this restoration project proposal since the focus will entirely be on the forest ecosystem, which dominates Inwood Hill Park. Nevertheless, it is important to note that documentation of former restoration projects performed by the Natural Resources Group (NRG) suggest that native species plantings were a success in the forest ecosystem. Note also that the plants in the ‘successional fields’ community type include Vinca minor, Wisteria floribunda, Lonicera spp., and Commelina communis, are garden plants which indicates where most of the residential areas had been built in the past (Loeb 1986).

The vegetation types are described below, in Table 1, according to dominant and subdominant species presence as well as, for reference, other sites with similar community types; descriptions and lists extracted directly from text in Loeb (1986). Table 2 is taken from Loeb (1986) as well and lists the tree and shrub species present for each vegetation type.

 

Table 1.  Six vegetation types: characteristic species (Loeb 1986)

Forest Community

Tree dominants; subdominants; other

Shrub; herb; vine dominants

Urban forests with similar community type

Slope forest

Oak (Quercus rubra, Q. alba, Q. prinus); Carya spp., Liriodendron tulipifera, Sassafras albidum; Acer rubrum, A. saccharum, Prunus serotina, Fraxinus Americana

Viburnum acerifolium, Rhus radicans; Eupatorium rugosum, Cimicifuga racemosa, and Gramineae

slope and flat upland of Forest Park, Queens; Alley Pond Park, Queens; ravine in Prospect Park, Brooklyn;  hemlock in NY Botanical Gardens, Bronx; upland of Seton Falls Park, Bronx; dry forest of Van Cortlandt Park, Bronx; west slope of Riverdale Park, Bronx; Staten Island Greenbelt

North-facing forest

Quercus prinus, Q.rubra, L. tulipifera; Acer rubrum, Prunus serotina

Hamamelis virginiana, Lindera benzoin; Impatiens capensis, Eupatorium rugosum, and Gramineae spp.

Unique to NYC; similar to Saint John’s Pond Preserve

Valley forest                         

Acer saccharum, L. tulipifera, oak

Lindera benzoin, Rhus radicans; Smilacina racemosa, Parthenocissus quinquefolia

lowland of Seton Falls Park, Bronx; moist sites of Van Cortlandt Park, Bronx;  parts of Cunningham Park, Queens; Blue Heron Pond Park, Staten Island

Successional forest

L.tulipifera, Q.alba, Q. rubra; Morus spp., Prunus serotina, Pyrus prunifolia

Rubus phoenicolasius; Alliaria officinalis, Impatiens capensis, Rhus radicans; Lonicera spp., Vinca minor

disturbed forest of Van Cortlandt Park, Bronx;  another section of Cunningham Park, Queens; west slope of Riverdale Park, Bronx; Central Park; swamp oak forest on Staten Island

Successional field

Morus spp., Prunus serotina, Ailanthus altissima; Pyrus prunifolia, Quercus rubra

no shrub; Gramineae spp. (dominant), Aster spp., Plantago spp., Trifolium spp. (subdominant); Vinca minor, Lonicera spp., Commelina communis, Wisteria floribunda

-

Salt marshes (6)

-

Spartina alterniflora, Iva frutescens (marsh 1-4); Phragmites communis, Ammophila breviligulata (marsh 1)

Simpler than barrier beach of Plum Beach, Brooklyn; and, high marshes of Pelham Bay Park, Bronx

 

 

Table 2. Six vegetation types: characteristic species’ densities (Loeb 1986)

 

Threats to the Inwood plant community are spawned from anthropogenic activity. Additive effects of human and dog walking, which leads to fragmentation, occasional automobile disturbances and fires, erosion, and soil acidification together damage the plant community by making it less productive and are factors that must be considered in the restoration plan (Loeb 1986). In addition, invasive species also threaten oak-tulip forests. The invasive species include garlic mustard (Alliaria petiolata), Asiatic bittersweet (Celastrus orbiculatus), Japanese honeysuckle (Lonicera japonica), Japanese stiltgrass (Microstegium vimineum), Japanese barberry (Berberis thunbergii), and mutiflora rose (Rosa multiflora) (New York Natural Heritage Program 2006). Oak trees have an additional threat, the invasive gypsy moth (Lymantria dispar), which may lead to tree mortality if defoliation by the moth and environmental factors combined are pervasive enough to stress the tree to its limits (New York Natural Heritage Program 2006). Nevertheless, the oak trees are a persistent plant, tolerant of many habitats; whereas tulip trees are more fragile (Wikipedia).

The tulip tree, sometimes also referred to as whitewood, yellow poplar, or tulip poplar (even though it is not a poplar), is in the Magnolia Family and prefers temperate climates (Wikipedia). In the New York area, the tree is actually at the limits of its geographic range (Ingelsby 1958). It is intolerant of extreme conditions such as drought and flooding, and it requires good, rich and moist, soil or deep and well drained loam for growth (Wikipedia), that is primarily found within the Clove (i.e. valley) of Inwood, which lies between the East and West Ridges (Ecological Planning Study 1987). Given an optimal substrate environment, tulip trees can grow to be quite high, such as Queens Giant near Alley Pond Park, Queens, which is the tallest (40.8m) and potentially oldest (350-400 years) tree in New York (“Queens Giant” 2006). Due to its height (up to 50m), the tulip tree is vulnerable to storm and particularly hurricane damage. In addition, fragmentation (e.g. road building) and human initiated disturbances such as development (e.g. residential, industrial) and habitat alteration (e.g. recreational overuse) are a threat (New York Natural Heritage Program 2006). The range of this species could be a lot larger area than it is now within the New York state were it not for these inundating factors (see Figure 3 for oak-tulip tree forest range in New York state). Currently, the patchy distribution is in the southeast New York area, in the lower Hudson Valley, Hudson Limestone Valley, and western Long Island Coastal Lowland (New York Natural Heritage Program 2006). There are only two Liriodendron species in the world (L. tulipifera and L. chinense), but when available these two can hybridize and produce offspring that grow faster than the parents (Wikipedia).

The approach of the restoration project is based on ‘build it and they will come’ scenario, the focus will be more on primary producers than animals. Though, in some cases, it may be better to know the customer before building the product, the maintenance and sustainability of the ecosystem should still depend on the basic infrastructure that is capable of survival in the given environment, which is the forest flora community itself and is the reason why the bottom up approach is preferable.

 

 

III.               Theory and considerations

 

Population genetics questions and issues are one of the primary points to consider in any restoration project, whether it be done as an introduction of new species at a site, a reintroduction of species that once occupied the site, or augmentation of a current population by the addition of more individuals to the site (Falk et al. 2006). The issues manifest themselves when we look at the three types of restoration materials (i.e. seeds or young plants) used: resident, translocated, and introduced (Falk et al. 2006). Presumably, resident materials, those native to the restoration site are preferable to use when one already has a large gene pool within the existing, though perhaps slightly fragmented, population. The goal of the project may be to simply augment the site. However, if the population is severely fragmented or small, such an approach would be unfavorable for it may lead to increased homozygosity due to inbreeding, or reproduction between closely related individuals, which in turn, may lead to inbreeding depression (Falk et al. 2006). Meaning that, individuals with increased homozygosity will have less genetic variability which may limit their resilience to natural disturbances. Natural selection will have a difficult time weeding out bad alleles if they are the only option available.

In the dominant tree species case, an augmentation restoration would be feasible since, at present, their numbers in the area are relatively high. However, translocated materials, those from a nearby site or historic range may be more preferable since the population is still fairly fragmented and prone to isolation and could probably use some additional alleles. In particular, potential source populations include southern Ontario, Illinois and all the states in between it and the southern New England states (Wikipedia); that is, assuming that the individuals are not extremely different genetically since they occupy the same latitude range (40-45oN). Perhaps the latitude at which these species is found is an important factor to consider when picking a suitable source population. According to Table 1, there exists a multitude of potential source populations for each vegetation type at Inwood. One need not go as far as Canada or Florida to obtain adequate sources.

Introduced restoration materials could potentially cause trouble to this community should hybridization occur between native species and the species from the source population. For example, should the introduced species of tulip tree, Liriodendron chinense, come from China or Vietnam, then the native population, Liriodendron tulipifera, could easily hybridize with it to produce faster growing offspring (Wikipedia), which may, in turn, be capable of reproducing more quickly than the parent species and eventually overtake them. Such a case may be classified as one of heterosis and a sign of inbreeding depression (Falk et al. 2006). Secondly, should the introduced species of L. tulipifera come from either Florida (semi-evergreen ecotype) or elsewhere in the southeastern U.S. (coastal plain swamp ecotype), then these species would be incompatible with the given restoration site because they, respectively, either endure very wet environments and flower earlier or they exhibit high flood tolerance (Wikipedia citing Parks et al. 1994). Unlike these ecotypes, the Inwood Park L. tulipifera is intolerant of flooding and presumably flowers later than the east central Florida ecotype. The increased flood or disturbance tolerance of an introduced tulip tree, may not only affect native tulip tree species, but community dynamics as well. The introduced ecotype may be so successful that it overtakes the oaks, which are thought to be more resilient to disturbance (Rudnicky 1989).

These alternative traits found in the southeast state ecotypes may not be all that bad, however. Initially, the alleles from these sites may indeed be negative where an increased genetic load and genetic pollution may hinder expression of the more suitable alleles, i.e. those which have been selected for by the native environment. On the other hand, some of the alleles carried by these ecotypes could get incorporated into the gene pool, increasing the gene pool and the tulip tree’s resilience to flooding, which may be helpful (as long as community dynamics are maintained; i.e. this additional resilience does not outcompete the oaks) considering the rise in sea level trend and potential for more frequent and severe hurricanes in the New England area due to global warming.

Ecophysiological constraints are a second critical issue to consider in designing a restoration project. According to Falk et al. (citing Chapin et al. 2002), ‘water availability is found repeatedly to be the resource most limiting to plant and ecosystem production.’ In particular, it is the lack of water and not the excess of which that acts as a greater stress on the plants and on primary productivity (Falk et al. 2006). For example, the tulip tree, Prunus serotina, Acer rubrum, and Betula lenta act as good invaders at dry or disturbed sites (e.g. clear cutting), which are usually oak dominated (Elliott 1994, Rudnicky 1989). These early successional species like lots of light/ are shade intolerant, like wet/moist and nutrient rich soil. However, severe or prolonged drought conditions may cause tulip tree, B.lenta and potentially the other species to decline (Elliott 1994). During drought conditions, oaks and small-size class individuals (<10cm in diameter) of all species in the community suffer high mortality losses (Elliott 1994). The most resilient species are Quercus prinus and Q. coccinea (not present at Inwood according to Loeb 1986), which show no reduction in growth, while L. tulipifera has a significant reduction in growth (Elliott 1994). (Case study, Elliott 1994, located in the Coweeta Basin, south Appalachian Forest.)

Flooding and drought responses and stresses are below ground processes. Above ground processes are important as well. Presumably, all trees utilize C3 photosynthesis (geog.ucsb.edu) making it difficult for other tree species to invade since they have no competitive edge that C4 plants (e.g. sedges, grasses) have, that is, if analysis is based solely on this ecophysiological characteristic (Falk et al. 2006, geog.ucsb.edu). For the restoration effort, we must consider the correct proportions to add of shrubs/vines/herbs (potential C4  plants) to tree species (C3 plants). For example, shade intolerant species like L. tulipifera seedlings may not grow if too many shrubs and other tree species are blocking the sun.

Inwood Park is located at the northern tip of Manhattan island making it a suitable example of metapopulation dynamics, a third restoration project consideration. If we look at Inwood Park alone we can say that it is isolated on an island. However, based on a range map, Figure 3 below (New York Natural Heritage Program 2006), and historical distribution (Wikipedia), we know that this particular community is surrounded by habitat patches with similar species composition in close proximity on a nearby island (Long Island) and the mainland (rest of New York state at south east corner). Therefore, we can consider a mainland-island model where source populations may theoretically come from north of Manhattan and seed dispersal between Manhattan island and Long Island can take place. Due to proximity of these locations (see Table 1, Figure 3), corridors may be unnecessary. According to Table 3 we see that seeds from six out of ten representative tree species are wind dispersed and that those that are dispersed by animals, such as acorns of oaks, may be transported from island to mainland (and vice versa) by bird species that feed on them (“Fruit and seed dispersal” 2002). In addition, due to the isolation medium (water), corridors may be difficult to impose on this particular system. Besides the effect of northerly winds striking the north facing slopes of Inwood may carry seeds from the mainland (Ecological Planning Study 1987). However, corridors between parks on Manhattan Island itself may be a possibility. In the end, seed dispersal mechanisms for other plant species in the community must be evaluated to know for certain what must be done (corridor, no corridor, seed disbursing animal introductions, etc.).

 

Table 3. Representative Tree Species and their Respective Seed Dispersal Mechanism

Tree Species

Seed Dispersal Mechanism

Resource

Tulip tree

Wind (long distance)

Horn et al. 2001

White Oak

Animal (birds, squirrels)

“Fruit and seed dispersal” 2002

Chestnut Oak

Animal (squirrel)

Wikipedia, “Chestnut oak” 2006

Red Oak

Animal (birds)

Wikipedia, “Northern Red oak” 2006

Black Oak

Animal

Wikipedia, “Black oak” 2006

Sugar Maple

Wind

Horn et al. 2006

Red Maple

Wind

Horn et al. 2006

Sweet Birch

Wind

Wikipedia, “Sweet birch” 2006

American Beech

Animal (raccoon, rabbit, squirrel)

Wikipedia, “American Beech” 2006

White Ash

Wind

Horn et al. 2006

 

 

Figure 2. Seeds of Representative Tree Species

(c) 2002 Steve Baskauf (all images), http://bioimages.vanderbilt.edu/

a) Tulip tree                         b) Red maple                       c) White oak

 

Next, we must consider the number of individuals to use in the restoration effort. A minimum viable population (MVP), or the least number of individuals needed to sustain a population through time at a given site (Falk et al. 2006), is preferred to be large, perhaps on the order of hundreds to thousands of individuals of a given species. The larger the population, the better it can withstand stochastic events such as natural catastrophes including floods, hurricanes, and droughts (Falk et al. 2006). On the tree scale one should probably use whole plants (i.e. seedlings), as opposed to seeds, for replanting efforts. Similar action may be necessary for the shrubs, vines, and herbs.

Further, we must consider the size of the metapopulation. A minimum viable metapopulation (MVM), or the least number of populations needed to sustain a metapopulation, should again be large (Falk et al. 2006). In this case, we consider that the populations on Long Island, the mainland, and on Manhattan are collectively a metapopulation. That is, each species in the Inwood Park community should have a representative population in the surrounding locations (see Table 1). Therefore, multiple metapopulations exist and also coexist in the community.  The buffer and reinforcement received by the Inwood Park populations from at least two other sources should help species and community persistence.

Another issue to consider is the minimum amount of suitable habitat (MASH), or the least number of habitat patches needed to sustain a metapopulation (Falk et al. 2006). According to Falk et al., 15-20 patches are required for MVM, though large patches, too, mean lower extinction risk (2006). Therefore, the three groups (mainland, Manhattan, long island) may be large enough to sustain each other through time; ideally, this may occur if human induced disturbances and development would recede from forest boundaries at a given population. For example, reducing parts of matrix (e.g. empty homes, deserted streets, etc.) that are infiltrating the restoration site in a substantial way will reduce patchiness and isolation problems within a population. Apparently, what this area really needs is a touch up every once in a while, where restoration serves to augment the existing site, which has persisted for centuries, by supplying the individuals which ‘immigrate’ to the site.  

 

Figure 3. Oak-tulip tree range at present (black); potential oak-tulip tree range (blue). Source: NYNHP Conservation Guide.

 

 

A fourth very important and seemingly overlooked restoration issue is that of evolutionary processes, particularly short-term contemporary evolution, occurring at the site post-restoration and, potentially, as a result of restoration. Restoration itself can act as a disturbance event at the site, which pushes the evolutionary trajectory on a new path to a new stable state; in other words, directional selection. Large populations and diverse communities are more likely to persist after a disturbance event, whereas small populations are more likely to go extinct (Falk et al. 2006); the large populations can handle the stress and adapt, whereas the small populations get overwhelmed. This concept further supports the inclusion of hundreds to thousands of tree species at Inwood Park in addition to those already present. However, the biggest hurdle is determining which source population to use so as to avoid compromising the fitness of the native group (Falk et al. 2006). For example, an introduced species or ecotype of a given species already in the park would force evolution on the native species or ecotype leaving two possible outcomes, either the native species or ecotype evolves or it dies.

However, we should not think of introduced ecotypes (or alleles) so negatively since they can also reduce inbreeding depression, increase genetic variation and long term evolutionary potential (Falk et al. 2006). In the long run, it may make more sense to introduce ecotypes from the lower latitudes or more distant longitudes into Inwood Park and monitor the evolutionary trajectory along the way. Nevertheless, the tree and shrub numbers are seemingly high enough in the vicinity of the restoration site (see Table 1, Figure 3) to suggest a safer alternative: use source populations from within the state that may be similar enough to prevent genetic load and genetic pollution, and, yet, diverse enough to maximize genetic diversity for the given ecotypes. Finally, the safest solution perhaps is a garden study assessment of all the possible ecotype source populations, which should reveal genetic differences among individuals more precisely (Falk et al. 2006); that is, assuming that various ecotypes of the given tree and shrub species exist within the same latitudinal range as Inwood Park and not just at the lower latitudes or more distant longitudes.  

            Successional stages and patterns must also be taken into consideration when deciding what proportions of tree and shrub species to add to the site. For example, L. tulipifera is a dominant species in early succession, or the first 50-150 years after disturbance, but the population size decreases significantly after >500 years if disturbance frequency is low (Busing 1995). Components of a disturbance regime include patch size, return interval, severity, and spatial dispersion (Busing 1995). Greatest increases in L. tulipifera numbers and basal area occur at small disturbance patches (.04 -.1ha), relatively short return intervals or disturbance occurrence at 50-100years, a large severity causing about 25% tree mortality, and large gaps of .1ha (Busing 1995). Therefore, L. tulipifera requires lots of space, large gaps determined by canopy tree size (>.04 ha or range of .04-.1ha), and light to proliferate and regenerate seeds naturally (Busing 1995). 

A single patch disturbance regime also increases tulip tree establishment (Busing 1995). (Case study, Busing 1995, located in the southern Appalachian cove forest.) Assuming that shade intolerant species occur at low frequency in old forests (Busing 1995) and that the low frequency is only due to shade and other community interactions (i.e. excluding anthropogenic disturbances or invasive species influences) we can determine the successional stage of the community and promote its trajectory towards a climax accordingly.

 

 

IV.              Current Problems

 

The three primary problems in the Inwood Hill Park forest ecosystem are fragmentation, erosion, and invasive species. Fragmentation is largely perpetuated by human activity, especially the use of paths within the park, the creation of side paths between the ‘paved’ or already established paths, and, not to mention, the largest fragmentation event to the park—the creation of the Henry Hudson Parkway in 1937, which split the park in nearly equal halves (Bresham 1990). Erosion is also a human perpetuated problem in two important ways. Firstly, the walking paths block plant growth that would otherwise stabilize the soil. Secondly, invasive species like the Norway Maple (Acer platanoides) and the Sycamore Maple (Acer pseudoplatanus) establish a dense canopy under which soil-stabilizing shrubs cannot grow (Ecological Planning Study 1987). The invasive species themselves are a threat to the indigenous community as they attempt to crowd out the native population.

 

V.                 Plan for restoration and its benefits

 

It is a very tricky thing to decide how to restore a site in the optimal condition of its time. We know that there are multiple reasons for changes in species composition. Community interactions like predation and competition are unavoidable interactions. Urbanization is an additional component in this environment in which certain plant species like Tsuga Canadensis, which is not listed for Inwood, cannot survive past seedling and need human introduction and protection to thrive (Rudnicky 1989). Natural disturbances like the hurricanes of 1938, 1944, and 1950 are equally important determinants of species composition (Rudnicky 1989). Succession after a disturbance such as drought, floods, or hurricanes, sets back the maturation trajectory of the community and must be considered. The question, therefore, is what sort of restoration project should be implemented? Should the forest be brought back to the stage it was in before urbanization or before the natural disturbance? Or, should we focus on the present state of the system and allow successional trends to determine the focus of the restoration effort? Since change is inevitable in any dynamic system, so the project ought to be structured to follow an adaptive management strategy that will follow changes in species composition up to the climax community. The goal is to determine the successional stage in which the forest is in currently and to build on that. For example, with increased disturbance frequency, more shade intolerant species (L. tulipifera, P.serotina, A. rubrum, B.lenta), which are early successional species, will thrive (Rudnicky 1989). The shade intolerant species tend to grow faster and like fragment edges more than shade tolerant species (Rudnicky 1989). Slow growing, young T. canadensis (not specific for Inwood) is sensitive to disturbance and may be considered a late successional species (Rudnicky 1989). Quercus spp. are more resilient to disturbance, though they too are slow growing (Rudnicky 1989).

Bringing the plant community of Inwood Hill Park back to the stage it was in before urbanization (c. 1600) may be a dream. The people in the vicinity of the park are too involved along the edges of the forest to permit drastic removals of soccer, baseball, handball and tennis fields, a hockey rink, children’s play areas, and fenced-off dog parks. The focus of the restoration project, instead, should be on the central forest ecosystem, located at the Eastern and Western Ridges and the Clove located in between them (see Appendix A for plant species composition at each site). The goal of the project is to limit the three threats –fragmentation, erosion, and invasive species—within the forest, while at the same time, appeasing the human community that is utilizing the park by building watch towers and publishing self-guided tour brochures.

 

Fragmentation

To limit fragmentation we would have to consider closing off paths that are underutilized, remove the pavement, and plant native trees, shrubs, and herbaceous species in their place. Focusing on paths along steep slopes will also help alleviate the erosion threat (Ecological Planning Study 1987). Further research on the exact location of the underutilized paths will have to be performed, but the focus is still within the forest-i.e. within and around the areas of the Clove and the East and West Ridges. The benefit of reducing fragmentation falls into reduction of the remaining threats. Limiting human treading within the forest will reduce disturbance on natives enabling them to counter invasive species dominance. Removal of excessive pathways will also limit soil erosion. Honing in on the most utilized paths and setting up the most strategically placed historical plaques along them may additionally help create the most efficient self-guided tour. Herbaceous species should be planted along most utilized paths to limit edge effects and provide a buffer between forest and matrix (i.e. the path). In addition, the remnant light posts, or ‘accent ruins’ (Bresham 1990), along the forest paths should be permanently removed in order to make room for planting and add to the aesthetic beauty of the forest.

 

Erosion/Invasives

To limit erosion is to also reduce the threat of invasive species. Active removal of invasive trees and vines at infested sites and replacement with native trees, shrubs, and especially herbaceous species, or species lacking a woody stem, will reduce erosion. Continual maintenance will limit the spread of invasive species. The benefit of reducing soil erosion along slopes is that less maintenance will have to be performed in the marshes. In addition, limiting soil erosion also prevents tree root exposure and makes for a healthier and more resilient ecosystem overall.

 

Watch Towers

To compensate for the trail loss, the project would build two 50 ft. wooden watch towers (Ecological Planning Study 1987) at already utilized sites along the forest edges. Instead of walking within the forest, the people can watch the forest ecosystem from a distance. The research on path and sport field usage, as well as ideal bird-watching sites would have to be performed before the towers are built. It is important to note that a group of students at the City College of New York cited as ‘Ecological Planning Study 1987’ came up with the idea of the towers at Inwood Hill Park, but current observations show that their plan was not implemented.

 

Self-guided Tours

To ensure appreciation of the park’s history and natural heritage either the existing historical plaques or additional landmark plaques would serve as stopping points in a self-guided tour of the park. The tour write-up should be easily accessible to the public either over the internet or in the form of a pamphlet obtainable at the Urban Ecology Center on site. Research on the area and evaluation of the state of the historic landmarks would have to be performed to create an efficient and least ecosystem intrusive tour. The hope is that by creating appreciation for the park’s history, the ecosystem will be more valued.

 

 

VI.              Timeline, budget, amount of work needed for restoration plan

 

The project will take 8 years to complete, where each year is comprised of two planting seasons one in the Spring and other in the Fall, and require substantial funding and volunteer assistance.  Potential sources of funding include 1996 Clean Water/Clean Air Bond Act, Lila Wallace-Reader’s Digest Foundation, National Fish and Wildlife Foundation, the US Environmental Protection Agency, EPA section 319 funds, NYC Environmental Fund, Urban Resources Partnership, New York State Department of Environmental Conservation (NRG Annual Report 2001), City of New York, National Oceanic and Atmospheric Administration, New York/New Jersey Harbor Estuary Program, and New York Department of State (Benepe and Wenskus 2003). Volunteers may come from Columbia University, NYU, New York Cares, High School for Environmental Studies, Mayor’s Office, Alley Pond Environmental Center, Boy Scout Troop 111, Neighborhood Initiatives Development Corporation, John Browne High School, J.F.K. High School, Martin DePorres High School, and many other groups and institutions (Benepe and Wenskus 2003).

 In the past, a simple land evaluation study cost $84,987 for an unknown acreage (Bresham 1990). The land evaluation in this project will include a survey of path usage and designation of prime location both for the two towers and the historical plaques. The estimate of the expected expenses for this initial land evaluation is around $10,000 and is extracted from the ‘capital’ and ‘personnel expertise’ funds since it takes survey work and landscape expertise to accomplish and should be complete within one year (see Figure 4). An 8 year restoration project, from 1994 to 2001, cost $6,288,000 for 6,000 acres of forest within the five NYC boroughs and was funded by multiple donors and sponsors (NRG Annual Report 2001). Inwood Hill Park comprises only 196.4 acres of the 6,000 in the former project. Therefore, if the money is split up proportionally by acreage, the expectation of cost for this project is around $206,000 for an 8 year period where sponsorship is anticipated from the above mentioned state and private organizations. However, only 6% ($12,360) of the overall award is expected to actually go toward the restoration project materials, such as plants and gardening equipment (Benepe and Wenskus 2003, see Figure 4). Presumably the ‘capital’ funds may go into the building of the towers and the ‘personnel services’ funds will pay forester and other non-volunteer personnel including construction worker salaries (Benepe and Wenskus 2003).  

 

Figure 4. Budget total $206,000 (Benepe and Wenskus 2003)

 

Capital =construction work ($129,780)

PS = Personnel Services ($63,860)

OTPS = Other Than Personnel Services ($12,360)

 

 

           

Consistent funding throughout the 8 years is crucial. Productivity in tree planting may decrease with decreasing funds (see Table 4). According to the NRG 2003 Annual Report, a decrease in funding by 8% from 2002 to 2003, leads to a 25% decrease in planting productivity of trees, shrubs, and herbaceous plants despite the 50% increase in volunteer numbers and the 20% increase in volunteer events. On the other hand, the decrease in productivity could be due to a 21% decrease in the number of projects performed throughout the year or the 18% decrease in staff. However, either of these decreases could be due to the funding sink. Since the source of the productivity decrease is likely due to decreased funding, it is important to stress the importance of having continual funding inflow in order to make the project a success over the eight year time span.

 

Table 4 (Benepe and Wenskus 2003).

 

            As in the past, the human community and neighborhoods in the area should be allowed to participate in the projects. NYC Department of Parks & Recreation Urban Park Rangers should continue to provide educational and recreational events for people of all ages. The Natural Resources Group (NRG), which is generally in charge of the restoration projects in the Northern Manhattan area (and other NYC parks), ought to engage the many potential volunteer groups that are available by announcing the work days for clearing and planting publicly, either via radio, television, or newspaper media, as well as through fliers and announcements via the parks website. Within one season, one full-time forester can plant 232 trees (NRG Annual Report 2001), which means that lots of additional volunteer help is necessary to make the project a success. For example, the maximum number of herbaceous plants planted in Northern Manhattan parks was 14,714 in 2001; the maximum number of trees and shrubs planted that same year was 10, 244 (NRG Annual Report 2001). In order to maintain the 2001 levels of tree plantings, at least 45 full-time foresters would be needed for the job. However, according to Benepe and Wenskus (2003), less than a dozen paid workers are designated for a given restoration project. Therefore, the volunteer groups are a crucial element in the restoration effort and the success of the restoration project both within the timeframe of the eight year project and beyond. Over an eight year project done from 1994 to 2001, 21,319 herbaceous and 26,713 trees and shrubs were planted in the Northern Manhattan (i.e. Inwood Hill Park) area alone (NRG Annual Report 2001). The standard and goals of this project should be based on the past project’s results. Therefore, the current project will attempt to match, if not exceed, the numbers of planted species from the 1994-2001 project.

 

            Timeline

            Year 1: Survey work to determine path usage and site preference for the two towers. Both the tower and self-guided-tour trail design including the historical plaque content and design should be a priority at this time. Group meetings with community leaders and members would provide advantageous input on the feasibility of the proposed project. The level of community acceptance or opposition of the project can also be gauged at this time and suggestions can be used to further modify the project.

 

            Year 2-8: Careful herbicide spraying of invasive species within the Cove and the East and West Ridges and especially along the paths will prepare the sites for native species planting (Emmerich 1999). Though spraying Asian vines and weeds does not remove them entirely, their growth is still restricted for a short period of time by spraying. Manual removal of the invasives should accompany herbicide spraying or be implemented alone should health concerns arise. Native species planting should follow. In addition, the unused paths will be removed and replaced with native species, especially the herbaceous understory plants. The removal and plantings occur twice a year, in the Spring and Fall months. The above procedure should be followed each season of each year.

 

The building of the two towers should commence during the second year of the project to compensate regular users of the park’s paths as soon as possible since paths under restoration will be closed off. In addition, the self-guided-tour pamphlets should be completed by the eight year to fall in line with the completion of the restoration project and the historical plaques. Therefore, timing of the restoration plan components is critical.

 

Invasive species for removal include:

 

Vines

Porcelainberry (Ampelopsis brevipedunculata)

Japanese honeysuckle (Lonicera japonica)

Oriental bittersweet (Celastrus orbiculatus)

 

Shrubs

Multiflora rose (Rosa multiflora)

Glossy buckthorn (Rhammus frangula)

 

Trees

Norway maple (Acer platanoides)

Sycamore maple (Acer pseudoplatanus)

Asian cork trees (Phellodendron japonicum, P. amurense)

(list taken from Emmerich 1999)

 

Oriental bittersweet (Celastrus orbiculatus) –the largest one is found in Queens at a diameter of 6.7 inches, see Figure 5, Benepe and Wenskus 2003)— and porcelainberry (Ampelopsis brevipedunculata) –which grow 20ft per yr, Benepe and Wenskus 2003) vines smother both saplings and mature trees (NRG Annual Report 2001).  Multiflora rose (Rosa multiflora), an erosion-promoting shrub, outcompetes seedlings and native shrubs (NRG Annual Report 2001). The Norway maple (Acer platanoides) outcompetes native trees and prevents groundcover growth (NRG Annual Report 2001). The removal of the maple yields to Tulip poplar (Liriodendron tulipifera) planting. A former removal took 6 years to complete (Benepe and Wenskus 2003). The overall removal focus, however, should not be so much on invasive trees as it should be on invasive vines and shrubs.

            According to Emmerich 1999, mature invasives are a priority for removal over younger forms of the invasive. Vine invasives should be removed before tree invasives if they occur at the same site (Emmerich 1999). When performing invasive species removals, the maintenance of shade and conopy cover is important to minimize evaporation from the soils. When invasive trees are targeted for removal they may be cut to pieces as logs and left behind to decompose (Emmerich 1999).

 

Figure 5. Largest oriental bittersweet invasive found in Queens, NY (Benepe and Wenskus 2003)

 

 

Figure 6. Progress of a restoration program done in the past at Inwood Hill Park. (Benepe and Wenskus 2003)

 

 

Before commencement of the restoration project, a permit from the New York State Department of Environmental Conservation (DEC) must be obtained in order to plant any type of plant (Native Species Planting Guide 1993). Source communities of plant species listed come from local nurseries and must be purchased. The Greenacre Foundation, North Manhattan Parks Administrator’s Office, the Urban Forest and Education Program, and NRG nurseries all have local plant stocks (Benepe and Wenskus 2003). The NRG Rare Plant Propagation Project used local plants from Inwood and other NYC parks and planted seedlings the season following collection (Rare Plant Propagation Project 2006). For larger plant species seedlings are used for planting. Apparently, seeds may be used for grasses and groundcover plantings. Nurseries growing local plants can be found in New Jersey, New York, Maryland, Tennessee, Wisconsin (for contact information see Native Species Planting Guide 1993).

            The seedlings come in several forms including ‘herbaceous plugs,’ ‘bareroot’ and ‘containerized’ tree seedlings, and balled-and-burlapped, or ‘B&B’ trees (see Figure 7, Benepe and Wenskus 2003). Planting containerized seedlings, or ‘seedlings grown in some type of pot or bag,’ instead of bareroot seedlings, or ‘seedlings lifted from open nursery beds for planting elsewhere’ is better; the containerized seedlings are bigger and survive better and can be planted in larger numbers at any given year because the planting season is longer for them (Benepe and Wenskus 2003). In addition, planting herbaceous plant types and installing biodegradable ‘cribbing and jute or coir mats’ through which the herbaceous species can grow, reduces erosion tremendously (Wenskus Dec. 2002). In order to reduce erosion in the former projects (Spring 2002/Fall 2002), more ‘groundcover herbaceous plants’ were planted (5,345/3,665) in Inwood, than containerized trees and shrubs (4,139/2,171), bareroot trees (825/-), or balled and burlapped trees (-/110) (Wenskus Jul. 2002). In 2003, twice as many herbaceous plants (29,135) were planted citywide than any other plant type, i.e. trees and shrubs (14,962) (Benepe and Wenskus 2003). Therefore, one can plant more herbaceous plants per season than shrubs and trees and these herbaceous plants are specifically planted for erosion control (NRG Annual Report 2001). The Natural Resources Group Forest Restoration Team (Seasonal) Planting Reports are excellent resources for basic information on the numbers of tree, shrub, and herbaceous species planted per park. However, the exact numbers and density of each tree, shrub, and herbaceous species planted at Inwood Hill Park specifically will perhaps be better estimated once the surveys are complete and the exact sites where unused paths, erosion prone slopes, and invasive threats are located. Nevertheless, the numbers of plants used in former NRG restoration projects will serve as guidelines for the current plan.

 

 

 

 

 

 

 

 

 

 

 

Figure 7. Examples of plant materials used by NRG for forest restoration projects (Benepe and Wenskus 2003).

 

Eighteen percent of Manhattan’s parkland consists of forest communities (Benepe and Wenskus 2003, Ecological Planning Study 1987). Therefore, focusing restoration work on Inwood Hill Park’s precious forest will help preserve the ecosystem for future generations of both park goers and forest wildlife. Focusing on the slope forest far above sea level will also ensure that at least some of the forest remains intact should sea levels rise as a result of ice cap melting triggered by global warming. The hardwood forest of Inwood may be as old as 200 years, but conifer species like the eastern white pine (Pinus strobus), eastern hemlock (Tsuga canadensis), pitch pine (Pinus rigida), and Virginia pine (Pinus virginiana) are cheaper than hardwoods and are more successful at ‘poor sites’ (Emmerich 1999). In addition, they serve as excellent habitat for owl and other forest bird species (Emmerich 1999). Therefore, implementation of these conifer species should be strongly considered in future projects. In the meantime and over the long term, as the eight year project winds down and ends, further and regular maintenance of the forest (i.e. removal of vines, weeds, and other invasives) either by expert crew or volunteer groups should be kept up for 5-10 years until the natives are on their own feet (David M. Smith in Emmerich 1999). A separate group or committee of trained personnel ought to be designated to work on managing such small scale projects annually and be provided with an annual budget suitable to accomplishing the task. As Dr. David M. Smith, professor Emeritus of Silviculture at Yale University said, ‘Having a complete cover of trees is, after all, the simplest and cheapest mode of vegetation control and management’ (Emmerich 1999). Therefore, a measure of success for the short term is the completion of the 8-year project proposed. In the long term, success should be measured by the persistence of the forest augmented by this plan.

 

 

 

 

 

 

 

 

References Cited

 

Benepe, A. & Wenskus, T.J. (2003). Natural Resources Group Forest Restoration Team. Annual Report. City of NY Parks & Recreation.

 

Bresham, J. (1990). North Manhattan Parks: A study. City of New York Parks & Recreation. David D. Dinking, Mayor; Henry J. Stern, Commissioner).

 

Busing, R.T. (1995). Disturbance and the population dynamics of Liriodendron tulipifera: simulations with a spatial model of forest succession. The Journal of Ecology, 83(1): 45-53.

 

Ecological Planning Study: Inwood Hill Park. City College of New York. Urban Landscape 365. Spring 1987.

 

Elliott, K.J. & Swank, W.T. (1994). Impacts of drought on tree mortality and growth in a mixed hardwood forest. Journal of Vegetation Science, 5(2): 229-236.

 

Emmerich, T., ed. (1999). Forest Conservation and Restoration in the City. A Report of the Urban Forest and Education Program. City Parks Foundation. 83p.

 

Falk, D.A., Palmer, M.A. & Zedler, J.B. 2006. Foundations of Restoration Ecology. Washington, D.C., U.S.: Island Press.

 

Horn. H.S., Nathan, R. &Kaplan, S.R. (2001). Long-distance dispersal of tree seeds by wind. Ecological Research, 16: 877-885.

 

Ingelsby, B. (1958). Distribution of the tulip tree (Liriodendron tulipifera L.) in southwestern New York. American Midland Naturalist, 59(2): 397-417.

 

Lefkowitz, A. & Greller, A.M. (1973). The distribution of tree species on the uplands of Cunningham Park, Queens County, New York. Bulletin of the Torrey Botanical Club, 100(5): 313-318.

 

Loeb, R.E. (1986). Plant communities of Inwood Hill Park, New York County, New York. Bulletin of the Torrey Botanical Club, 113(1): 46-52.

 

Native Species Planting Guide for NYC and vicinity. (1993). Natural Resources Group.City of NY Parks & Recreation. 130p.

 

Natural Resources Group Forest Restoration Team, 1994-2001. Annual Report. Dec. 12, 2001. Nov. 30, 2006. <http://www.nycgovparks.org/sub_about/parks_divisions/nrg/documents/NRG_Summary_1994-2001.pdf>

 

Rare Plant Propagation Project. NRG. NYC Dept. of Parks & Recreation. Nov. 30, 2006. <http://www.nycgovparks.org/sub_about/parks_divisions/nrg/nrg_rareplant.html>

 

Rudnicky, J.L. & McDonnell, M.J. (1989). Forty-eight years of canopy change in a hardwood-hemlock forest in New York City. Bulletin of the Torrey Botanical Club, 116(1): 52-64.

 

Wenskus, T. & Kortbein, P. Dec. 19, 2002. Nov. 30, 2006. Natural Resources Group Forest Restoration Team Fall 2002 Summary. <http://www.nycgovparks.org/sub_about/parks_divisions/nrg/documents/NRG_Summary_Fall_2002.pdf>

 

Wenskus, T. & Kortbein, P. Jul. 11, 2002. Nov. 30, 2006. Natural Resources Group Forest Restoration Team Spring 2002 Summary. <http://www.nycgovparks.org/sub_about/parks_divisions/nrg/documents/NRG_Summary_Spring_2002.pdf>

 

Online sources:

 

“A brief history of Inwood Hill Park11 Oct. 2006 <http://www.rburns.com/TBG/Inwood/ihphist.htm>

 

Forest Preserve District of Cook County (Illinois). “The Tulip Tree.” Nature Bulletin No. 303-A. 20 April 2006. 11 Oct. 2006. <http://www.newton.dep.anl.gov/natbltn/300-399/nb303.htm>

 

“Fruit and seed dispersal” 2002. 7 Dec. 2006. Department of Biological Sciences of

Vanderbilt University. <http://www.cas.vanderbilt.edu/bioimages/pages/fruit-seed-dispersal.htm>

 

Inwood Hill Park11 Oct. 2006 <http://www.rburns.com/TBG/Inwood/park.htm>

 

New York City Department of Parks & Recreation. Northern Manhattan Parks Forest Restoration page. 11 Oct. 2006. <http://www.nycgovparks.org/sub_about/parks_divisions/nrg/nrg_manhattan_restoration.html>

 

New York Natural Heritage Program. Conservation Guide: Oak-Tulip Tree Forest. 10 Aug. 2006. 11 Oct. 2006. <http://www.acris.nynhp.org/report.php?id=9985>

 

 

Renner, James. Washington Heights & Inwood Online. “Inwood Hill Park” Sept. 2003. 11 Oct. 2006 < http://www.washington-heights.us/history/archives/inwood_hill_park_96.html>

 

The physical environment and the distribution of life, ppt. lecture. 18 April 2006. 11 Oct. 2006.

               

Wikipedia. “American beech”.  6 Nov. 2006. 7 Dec. 2006.

            <http://en.wikipedia.org/wiki/Sweet_birch>

 

Wikipedia. “Black oak”. 26 Nov. 2006. 7 Dec. 2006. <http://en.wikipedia.org/wiki/Quercus_velutina>

 

Wikipedia. “Chestnut oak”. 22 Oct. 2006. 7 Dec. 2006. <http://en.wikipedia.org/wiki/Quercus_montana>

 

Wikipedia. Henry Hudson Parkway18 Oct. 2006. 2 Dec. 2006. <http://en.wikipedia.org/wiki/Henry_Hudson_Parkway>

 

Wikipedia. “Liriodendron” 19 Oct. 2006. 20 Oct. 2006. 

            <http://en.wikipedia.org/wiki/Tulip_tree>

 

Wikipedia. “Liriodendron tulipifera” 17 Oct. 2006. 20 Oct. 2006.

            <http://en.wikipedia.org/wiki/Liriodendron_tulipifera>

 

Wikipedia. “List of Quercus Species” 9 Oct. 2006. 11 Oct. 2006.

<http://en.wikipedia.org/wiki/List_of_Quercus_species>

 

Wikipedia. “Northern Red Oak” 20. Nov. 2006. 7 Dec. 2006. <http://en.wikipedia.org/wiki/Quercus_rubra>

 

Wikipedia. “Oak” 19 Oct. 2006. 20 Oct. 2006. <http://en.wikipedia.org/wiki/Oak_tree>

 

Wikipedia. “Queens Giant” 27 July 2006. 11 Oct. 2006.  

<http://en.wikipedia.org/wiki/Queens_Giant>

 

Wikipedia. “Sweet Birch”. 5 Nov. 2006. 7 Dec. 2006.

            <http://en.wikipedia.org/wiki/Sweet_birch>

 

 

 

Appendix A

Native Plants found at Inwood Hill Park including the Cove, and the East and West Ridges.
Note: Appendix A is constructed from information provided in the Native Species Planting Guide 1993
Plants in bold are dominant in the given plant community.
See Native Species Planting Guide (1993) for further instruction on planting these species (i.e. by ‘plant material type’ such as B&B, containerized, bareroot, plugs, and season for planting, etc.), the benefits to wildlife of and exact nursery locations for each species.

I.  Appalachian oak-hickory forest (East and West Ridges): hardwood forest on hilltop or hillsides facing south or west; (sandy) loam soils, dry at hilltops and moist at hill bottom
Dominants: Northern red (at hill bottom), black (hillside), and white (hilltop) oak; shagbark, bitternut, mockernut hickories; American beech at hill bottom

Ferns    Hay-scented fern (Dennstaedtia punctilobula)
    Christmans fern (Polystichum acrostichoides)

Graminoids    Broomsedge (Andropogon virginicus)
        Pennsylvania sedge (Carex pensylvanica)
        Bottlebrush sedge (Elymus hystrix)

Forbs    White wood aster (Aster divaricatus)
    Stiff-leaf aster (Aster linariifolius)
    Spotted Joe-Pye weed (Eupatorium maculatum)
    White boneset (Eupatorium rugosum)
    Woodland sunflower (Helianthus divaricatus)
    Wild bergamot (Monarda fistulosa)
    Solomon’s seal (Polygonatum biflorum)
    Thin-leaf coneflower (Rudbeckia triloba)
    False Solomon’s seal (Smilacina racemosa)

Shrubs    Shadblow (Amelanchier canadensis)
    New Jersey tea (Ceanothus americanus)
    Red-panicled dogwood (Cornus racemosa)   
    Bush honeysuckle (Diervilla lonicera)
    Mountain laurel (Kalmia latifolia)
    Pinxter azalea (Rhododendron periclymenoides)
    Pasture Rose (Rosa carolina)
    Northern blackberry (Rubus allegheniensis)
    Lowbush blueberry (Vaccinium angustifolium)
    Mapleleaf viburnum (Viburnum acerifolium)
    Blackhaw viburnum (Viburnum prunifolium)

Trees    Red maple (Acer rubrum)
    Sugar maple (Acer saccharum)
    Serviceberry (Amelanchier arborea)
    Black birch (Betula lenta)
    Gray birch (Betula populifolia)
    Shagbark hickory (Carya ovata)
    Flowering dogwood (Cornus florida)
    White ash (Fraxinus americana)
    Witch hazel (Hamamelis virginiana)
    Tulip tree (Liriodendron tulipifera)
    American hophornbeam (Ostrya virginiana)
    Eastern white pine (Pinus strobus)
    Black cherry (Prunus serotina)
    White oak (Quercus alba)
    Chestnut oak (Quercus prinus)
    Northern red oak (Quercus rubra)
    Black oak (Quercus velutina)
    Common sassafras (Sassafras albidum)




II. Rich Mesophytic Forest (the Clove): Hardwood or mixed forest; occurs on less steep areas; Moist, but well drained and deep soils.
Dominants: Oak-tulip (tuliptree, red maple, red and black oak); beech-maple (sugar maple, American beech)

Ferns    Lady fern (Athyrium filix-femina)
    Toothed woodfern (Dryopteris carthusiana)
    Marginal woodfern (Dryopteris marginalis)
    Sensitive fern (Onoclea sensibilis)
    Interrupted fern (Osmunda claytoniana)
    Christmas fern (Polystichum acrostichoides)
    New York fern (Thelypteris noveboracensis)

Forbs    White-wood aster (Aster divaricatus)
    Purple Joe-Pye weed (Eupatorium purpureum)
    White snakeroot (Eupatorium rugosum)
    Wild geranium (Geranium maculatum)
    Forest sunflower (Helianthus decapetalus)
    Jewelweed (Impatiens capensis)
    Canada mayflower (Maianthemum canadense)
    Partridgeberry (Mitchella repens)
    Oswego tea (Monarda didyma)
    Wild bergamot (Monarda fistulosa)
    White beardtongue (Penstemon digitalis)
    Mayapple (Podophyllym peltatum)
    Solomon’s seal (Polygonatum biflorum)
    Thin-leaf coneflower (Rudbeckia triloba)
    False Solomon’s seal (Smilacian racemosa)
    Foamflower (Tiarella cordifolia)

Shrubs    Shadblow (Amelanchier canadensis)
    Alternate-leaved dogwood (Cornus alternifolia)
    Bush honeysuckle (Diervilla lonicera)
    Spicebush (Lindera benzoin)
    Pinxter azalea (Rhododendron periclymenoides)
    Northern blackberry (Rubus allegheniensis)
    Lowbush blueberry (Vaccininum angustifolium)
    Mapleleaf viburnum (Viburnum acerifolium)
    Arrowwood (Viburnum dentatum)   
    Blackhaw viburnum (Viburnum prunifolium)

Trees    Red maple (Acer rubrum)
    Silver maple (Acer saccharum)
    Serviceberry (Amelanchier arborea)
    Black birch (Betula lenta)
    American hornbeam (Carpinus caroliniana)
    Shagbark hickory (Carya ovata)
    Alternate-leaved dogwood (Cornus alternifolia)
    Flowering dogwood (Cornus florida)
    White ash (Fraxinus americana)
    Green ash (Fraxinus pensylvanica)
    Witch hazel (Hamamelis virginiana)
    Sweet gum (Liquidambar styraciflua)
    Tulip tree (Liriodendron tulipifera)
    Black tupelo (Nyssa sylvatica)
    American hophornbeam (Ostrya virginiana)
    Eastern white pine (Pinus strobus)
    American sycamore (Platanus occidentalis)
    Black cherry (Prunus serotina)
    White oak (Quercus alba)
    Pin oak (Quercus palustris)
    Northern red oak (Quercus rubra)
    Black oak (Quercus velutina)
    Common sassafras (Sassafras albidum)
    American linden (Tilia Americana)

Note: Appendix A is constructed from information provided in the Native Species Planting Guide 1993

See Native Species Planting Guide (1993) for further instruction on planting these species (i.e. by ‘plant material type’ such as B&B, containerized, bareroot, plugs, and season for planting, etc.), the benefits to wildlife of and exact nursery locations for each species.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Appendix B

 

 Representative wildlife species of Inwood Hill Park

Wildlife Taxa

Representative Species

Fish

Goose fish

 

Atlantic Needle Fish

 

Gobie

 

Baby Sea Robin

 

Hog Choker

 

Fluke

 

Blue Black Herring

 

Tomcod

 

Pipe Fish

 

White Mullet

 

Mackerel

 

Blue Fish

 

Striped Bass

 

White Perch

 

Lafayette

 

American Eels

 

Bay anchovies

 

Tidal Water Silverfish

 

Atlantic Silverside

 

Sturgeon

 

Menhaden

 

Shad

 

Winter Flounder

 

White Catfish

 

Mummichop

 

Carp

Crustaceans

Green Crab

 

Blue Claw Crab

 

Fiddler Crab

 

Black Fingered Mud Crab

 

White Fingered Mud Crab

 

Horse Shoe Crab

 

Harris Mud Crab

 

Scud

 

Parasitic Isopod

 

Barnacle

Mollusks

Marsh Snail

 

Soft-shell Clam

Miscellaneous

Bloodworm

 

Leidy’s Comb Jelly

 

Sandworm

Mammals

Norway rat

 

Big Brown Bat

 

Grey Squirrel

 

Raccoon

 

Muskrat

 

House Mouse

 

Red fox

Birds

Laughing Gull

 

Ring-Bill Gull

 

Herring Gull

 

Great Black-Backed Gull

 

Mallard

 

Black Duck

 

Widgeon

 

Eurasian Tufted Duck

 

Gadwall

 

Northern Shoveler

 

Greenwing Teal

 

Ruddy Duck

 

Ring-necked Duck

 

Canvasback Duck

 

Buffle Head Duck

 

Redhead Duck

 

Greater Scaup

 

Canada Goose

 

Nute Swan

 

Great White Egret

 

Snowy Egret

 

Great Heron

 

Little Blue Heron

 

Black-crowned Night Heron

 

Common Loon

 

Double-crested Cormorant

 

Red-winged Blackbird

 

Belted Kingfisher

 

Fish Crow

 

Swamp Sparrow

 

Bank Swallow

 

Solitary Sandpiper

 

Spotted Sandpiper

 

Semipalmated Sandpiper

 

Lesser Yellowlegs

 

Sanderling

 

Osprey

 

Kestrel

 

Least Bittern

 

Downy Woodpecker

 

White-breasted Nuthatch

 

Tufted Titmouse

 

Hooded Warbler

 

Connecticut Warbler

 

Ringed Neck Warbler

 

Mourning Dove

 

Wooded Thrush

 

Mockingbird

 

Indigo Bunting

 

Cardinal

Note: Appendix B is constructed entirely from information provided in the Ecological Planning Study 1987

The list is based on sightings; no actual counts were provided. Therefore, one must use caution in interpreting the provided list for some species that existed in 1987 may not be around today. In addition, some of these species may have been replaced by other wildlife species.

 

Last Updated by James Danoff-Burg, 20 Dec 06