According to the USDA Forest Service's Silvics Manual (1990), "the "national champion" American holly (Ilex opaca), in the Congaree Swamp of South Carolina, is 30.2 m (99 ft) tall with a circumference of 248 cm (98 in), a trunk diameter of 79 cm (31 in), and a crown diameter of 12.2 m (40 ft)." American holly growth within its range on Long Island and other parts of New York is much more limited due to either persistent winds in a severe coastal climate, nutrient deficient soils, and/or periodic or extensive cold or low-growth periods at the northern limit of its range.
There is only one documented occurrence statewide and very few or no additional occurrences are suspected. The known occurrence has good viability and is largely protected on public and private conservation land. The community is restricted to the eastern extreme of the Coastal Lowlands and is concentrated on the Montauk Peninsula, a morainal plateau. While the acreage and extent of coastal oak-holly forest in New York may be increasing slightly, its condition is likely to be decreasing. Overall the community's trend is stable to slightly decreasing. Threats include invasion by exotic species, heavy deer browse, recreational overuse, and development pressures.
While the acreage and extent of coastal oak-holly forest in New York may be increasing slightly, its condition is likely to be decreasing. Overall the community's trend is stable to slightly decreasing. The size of the one known occurrence of this community is suspected to be increasing slightly and very slowly. It is moderately well protected and managed and the surrounding protected lands support successional maritime forest, which appears to be succeeding slowly to this type. Condition, on the other hand, is possibly slowly declining because of heavy deer browse.
The number, extent, and viability of coastal oak-holly forests in New York are suspected to have declined substantially over the long-term. These declines are likely correlated with coastal development and associated changes in landscape connectivity.
Generally, the one documented occurrence of this community is well protected and managed and is somewhat buffered from natural catastrophic events. Primary threats include timber removal, recreational development and overuse, additional residential development, spread of exotics into less disturbed mature forest area, and continued landscape fragmentation. Heavy deer browse could also potentially alter species composition.
Monitor for disturbance by park visitors. Leave downed wood in place and allow forest maturation to an old-growth state. Consider deer exclosures or population management, particularly if studies confirm that canopy species recruitment is being affected by heavy browse. Generally, management should focus on activities that help maintain regeneration of the species associated with this community. Deer have been shown to have negative effects on forest understories (Miller et al. 1992, Augustine and French 1998, Knight 2003) and management efforts should strive to ensure that tree and shrub seedlings are not so heavily browsed that they cannot replace overstory trees.
Fragmentation of coastal forests should be avoided. It is also important to maintain connectivity with adjacent natural communities not only to allow nutrient flow and seed dispersal, but to allow animals to move between them seasonally. Strive to minimize fragmentation of large forest blocks by focusing development on forest edges, minimizing the width of roads and road corridors extending into forests, and designing cluster developments that minimize the spatial extent of the development. Development projects with the least impact on large forests and all the plants and animals living within these forests are those built on brownfields or other previously developed land. These projects have the added benefit of matching sustainable development practices (for example, see: The President's Council on Sustainable Development 1999 final report, US Green Building Council's Leadership in Energy and Environmental Design certification process at http://www.usgbc.org/).
Surveys for additional examples of this community on the Montauk Peninsula are needed. The primary lead is from the Hither Woods-North site. Secondary efforts should focus elsewhere on the moraine of the South Fork of Long Island and on the barrier islands of the south shore of Long Island.
A critical assessment of the long-term effects of heavy deer browse on this community, particularly addressing canopy species seedling recruitment, is needed.
The community is restricted to the eastern extreme of the Coastal Lowlands and is concentrated on the Montauk Peninsula, a morainal plateau. Known and suspected examples are limited to this peninsula. It is very unlikely to be found elsewhere.
Extends north probably as far as Cape Cod and the Bristol Lowlands of Massachusetts (Barbour, Lundgren, and Sneddon, pers. comm. 1997). Extends south through Rhode Island, New Jersey, and possibly Delaware. Not currently known from Connecticut (NatureServe 2009).
A mixed deciduous-evergreen broadleaf forest that occurs on somewhat moist and moderately well drained silt and sandy loams in low areas on morainal plateaus. The elevation afforded by the raised plateau protects these areas from overwash and salt spray. In New York State, this forest is best developed on the narrow peninsulas of eastern Long Island. The trees are usually not stunted, and are removed from the pruning effects of severe salt spray. The canopy of a mature stand is usually up to about 20 m (65 ft) tall.
The dominant canopy trees are black oak (Quercus velutina), blackgum (Nyssa sylvatica), red maple (Acer rubrum) and American beech (Fagus grandifolia). Holly (Ilex opaca) is abundant in the subcanopy and tall shrub layers. Other characteristic trees at lower density include sassafras (Sassafras albidum), serviceberry (Amelanchier canadensis), and white oak (Quercus alba). Shrubs such as highbush blueberry (Vaccinium corymbosum), witch hazel (Hamamelis virginiana), mountain laurel (Kalmia latifolia) and arrowwood (Viburnum dentatum var. lucidum) are common in the understory. Vines such as Virginia creeper (Parthenocissus quinquefolia), poison ivy (Toxicodendron radicans), and common greenbrier (Smilax rotundifolia), sawbrier (S. glauca), and grape (Vitis spp.) are at very low abundance in the understory, and usually do not grow up into the canopy. Characteristic groundlayer herbs include New York fern (Thelypteris noveboracensis), star flower (Trientalis borealis) and Swan's sedge (Carex swanii). There may be small, damp depressions that are somewhat boggy; species found in these depressions include blackgum (Nyssa sylvatica), serviceberry, highbush blueberry, and chokeberry (Photinia melanocarpa).
Known examples of this community have been found at elevations between 7 feet and 89 feet.
The best time to see this community is when the red berries of American holly (Ilex opaca) ripen, and this occurs between September and December. The berries can be seen through most of the winter as long as migrating birds, such as cedar waxwings, or other wildlife do not consume them.
This New York natural community encompasses all or part of the concept of the following International Vegetation Classification (IVC) natural community associations. These are often described at finer resolution than New York's natural communities. The IVC is developed and maintained by NatureServe.
This New York natural community falls into the following ecological system(s). Ecological systems are often described at a coarser resolution than New York's natural communities and tend to represent clusters of associations found in similar environments. The ecological systems project is developed and maintained by NatureServe.
Acer rubrum var. rubrum (common red maple)
Fagus grandifolia (American beech)
Ilex opaca var. opaca (American holly)
Nyssa sylvatica (black-gum, sour-gum)
Quercus alba (white oak)
Quercus velutina (black oak)
Sassafras albidum (sassafras)
Amelanchier canadensis var. canadensis (coastal shadbush)
Hamamelis virginiana (witch-hazel)
Ilex opaca var. opaca (American holly)
Kalmia latifolia (mountain laurel)
Sassafras albidum (sassafras)
Vaccinium corymbosum (highbush blueberry)
Viburnum dentatum var. lucidum (smooth arrowwood)
Parthenocissus quinquefolia (Virginia-creeper)
Smilax glauca (white-leaved greenbrier)
Smilax rotundifolia (common greenbrier)
Toxicodendron radicans ssp. radicans (eastern poison-ivy)
Carex swanii (Swan's sedge)
Lysimachia borealis (starflower)
Thelypteris noveboracensis (New York fern)
This figure helps visualize the structure and "look" or "feel" of a typical Coastal Oak-Holly Forest. Each bar represents the amount of "coverage" for all the species growing at that height. Because layers overlap (shrubs may grow under trees, for example), the shaded regions can add up to more than 100%.
Augustine, A.J. and L.E. French. 1998. Effects of white-tailed deer on populations of an understory forb in fragmented deciduous forests. Conservation Biology 12:995-1004.
Edinger, G. J., D. J. Evans, S. Gebauer, T. G. Howard, D. M. Hunt, and A. M. Olivero (editors). 2014. Ecological Communities of New York State. Second Edition. A revised and expanded edition of Carol Reschke’s Ecological Communities of New York State. New York Natural Heritage Program, New York State Department of Environmental Conservation, Albany, NY. https://www.nynhp.org/ecological-communities/
Edinger, Gregory J., D.J. Evans, Shane Gebauer, Timothy G. Howard, David M. Hunt, and Adele M. Olivero (editors). 2002. Ecological Communities of New York State. Second Edition. A revised and expanded edition of Carol Reschke's Ecological Communities of New York State. (Draft for review). New York Natural Heritage Program, New York State Department of Environmental Conservation. Albany, NY. 136 pp.
Greller, Andrew M. 1977. A classification of mature forests on Long Island, New York. Bull. Torrey Bot. Club 140 (4):376-382.
Knight, T.M. 2003. Effects of herbivory and its timing across populations of Trillium grandiflorum (Liliaceae). American Journal of Botany 90:1207-1214.
Miller, S.G., S.P. Bratton, and J. Hadidian. 1992. Impacts of white-tailed deer on endangered and threatened vascular plants. Natural Areas Journal 12:67-74.
NatureServe. 2009. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://www.natureserve.org/explorer. (Data last updated July 17, 2009)
New York Natural Heritage Program. 2022. New York Natural Heritage Program Databases. Albany, NY.
Reschke, Carol. 1990. Ecological communities of New York State. New York Natural Heritage Program, New York State Department of Environmental Conservation. Latham, NY. 96 pp. plus xi.
Sneddon, L., M. Anderson and K. Metzler. 1996. Community alliances and elements of the eastern region. Second draft. Unpublished report. The Nature Conservancy, Eastern Region Conservation Science, Boston, MA. April 11. 234 pp.
Sneddon, L., M. Anderson, and J. Lundgren. 1998. International classification of ecological communities: terrestrial vegetation of the northeastern United States. July 1998 working draft. Unpublished report. The Nature Conservancy, Eastern Conservation Science and Natural Heritage ProgramS of the northeastern United States, Boston, MA. July 1998.
Taylor, Norman. 1923. The vegetation of Long Island, Part I. The vegetation of Montauk: A study of grassland and forest. Memoirs Brooklyn Botanical Garden. 2:1-107.
This guide was authored by: Aissa Feldmann
Information for this guide was last updated on: April 7, 2021
Please cite this page as:
New York Natural Heritage Program. 2022. Online Conservation Guide for Coastal oak-holly forest. Available from: https://guides.nynhp.org/coastal-oak-holly-forest/. Accessed May 18, 2022.