Pignut hickory (Carya glabra), and sweet pignut hickory (Carya ovalis) are two species of hickory that occur within coastal oak-hickory forests. These two species of hickory are actually very difficult to distinguish from each other most of the year. The main difference between the two species is the husk of the fruit. "The fruit of pignut hickory is pearshaped and the husks splits only about halfway down. This last feature is the only trustworthy one, since the other characteristics intergrade" (Harlow 1957).
There are less than 10 documented occurrences statewide. These occurrences have good viability and are protected on private or public conservation land. The community is restricted to interior portions of coastal lowlands in Suffolk and possibly Nassau Counties and is concentrated on knolls and mid to upper slopes of moraines. The acreage, extent, and condition of coastal oak-hickory forests in New York is suspected to be declining.
The acreage, extent, and condition of coastal oak-hickory forests in New York is suspected to be declining due to fragmentation and extirpation from residential and commercial development, heavy deer browse, and invasive species.
The number, extent, and viability of coastal oak-hickory forests in New York are suspected to have declined substantially over the long-term. These declines are likely correlated with the settlement of Long Island and the subsequent residential, agricultural and commercial development.
The threats to the coastal oak-hickory forest are many and varied: displacement of the community by commercial and residential development; invasive species; roads and trails causing forest fragmentation and erosion; and deer browse. Some of the invasive species that have been observed in the forest include Japanese barberry (Berberis thunbergii), Black locust (Robinia pseudo-acacia), bittersweet (Celastrus orbiculatus), garlic mustard (Alliaria petiolata) and multiflora rose (Rosa multiflora). Deer browse on seedlings and saplings are causing a loss of forest canopy regeneration.
To promote a dynamic forest mosaic, allow natural processes, including gap formation from blowdowns and tree mortality, as well as, in-place decomposition of fallen coarse woody debris and standing snags, to operate, particularly in mature and old growth examples (Spies and Turner 1999). Management efforts should focus on the control or local eradication of invasive exotic plants and the reduction of white-tailed deer densities. 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. If active forestry must occur, use silvicultural techniques and extended rotation intervals that promote regeneration of a diversity of canopy, subcanopy and shrub species over time (Busby et al. 2009) while avoiding or minimizing both short-term and persistent residual disturbances such as soil compaction, loss of canopy cover due to logging road construction, and the unintended introduction of invasive plants.
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/). A cross-section of coastal oak-hickory forest occurrences should be protected, including the largest ones, the most mature ones, and the ones in the best landscape block.
Survey for additional large examples in central to western Suffolk County. Some leads to follow up on include Caleb Smith State Park, Wildwood State Park, and Butler-Huntington Preserve among others.
A critical assessment of the long-term effects of heavy deer browse on this community, particularly addressing oak and other canopy species seedling recruitment, is needed.
Coastal oak-hickory forests are restricted to the coastal lowlands in Suffolk and possibly Nassau Counties. They are concentrated on knolls and mid to upper slopes of glacial moraines. The range of this community possibly extends westward into northeastern Nassau County and on the end moraine of western Long Island (Greller 1977).
This natural community occurs along the coast from Maine to Maryland. This community is similar to the mesic coastal plain mixed oak forest of New Jersey.
The forest is usually codominated by two or more species of oaks, usually white oak (Q. alba), black oak (Quercus velutina) and chestnut oak (Q. montana). Scarlet oak (Quercus coccinea) is also a common associate. Mixed with the oaks, usually at moderate densities, are one or more of the following hickories: pignut (Carya glabra), mockernut (C. alba), and sweet pignut (C. ovalis). These hickories can range from nearly pure stands to as little as about 25% cover. There is typically a subcanopy stratum of small trees and tall shrubs including flowering dogwood (Cornus florida) and highbush blueberry (Vaccinium corymbosum). The shrublayer and groundlayer flora may be diverse. Common low shrubs include maple-leaf viburnum (Viburnum acerifolium), blueberries (Vaccinium angustifolium, V. pallidum) and black huckleberry (Gaylussacia baccata). Characteristic groundlayer herbs are Swan's sedge (Carex swanii), panic grass (Panicum dichotomum), poverty grass (Danthonia spicata), cow-wheat (Melampyrum lineare), spotted wintergreen (Chimaphila maculata), rattlesnake weed (Hieracium venosum), white wood aster (Aster divaricatus), false Solomon's seal (Maianthemum racemosum), Pennsylvania sedge (Carex pensylvanica), and white goldenrod (Solidago bicolor).
A hardwood forest with oaks (Quercus spp.) and hickories (Carya spp.) codominant that occurs in dry well-drained, loamy sand of knolls, upper slopes, or south-facing slopes of glacial moraines of the Atlantic coastal plain.
Known examples of this community have been found at elevations between 4 feet and 150 feet.
Early spring is a good time to catch many of the understory trees and shrubs in bloom. Flowering dogwood and maple-leaf viburnum provide visual sprays of color in the spring. Mid to late summer is a good time to snack on ripening blueberries and huckleberries.
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.
Percent cover
This figure helps visualize the structure and "look" or "feel" of a typical Coastal Oak-Hickory 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.
Busby, Posy E. and G. Motzkin. 2009. Dwarf beech forests in coastal New England: topographic and edaphic controls on variation in forest structure. American Midland Naturalist 162(1): 180-194.
Busby, Posy E., G. Motzkin and B. R. Hall. 2009. Distribution and dynamics of American beech in coastal southern New England. Northeastern Naturalist 16(2): 159-176.
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, A. M., J. M. Mansky, and R. E. Calhoon. 1982. An oak, hickory-dogwood forest on central Long Island, New York. Bulletin of the Torrey Botanical Club 109(2): 219-225.
Greller, Andrew M. 1977. A classification of mature forests on Long Island, New York. Bull. Torrey Bot. Club 140 (4):376-382.
Harlow, William M. 1957. Trees of the eastern and central United States and Canada. Dover publications Inc. New York, NY.
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. 2023. 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.
Rosza, R. and K. Metzler. 1982. Plant communities of Mashomack. In: The Mashomack Preserve Study. Vol. 2: Biological Resources. S. Englebright, ed. The Nature Conservancy, East Hampton, New York.
Sneddon, L. 1998. North Atlantic Coast classification. Unpublished report. The Nature Conservancy, Eastern Conservation Science, Boston, MA. July 1998.
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.
Spies, T.A. and M.G. Turner. 1999. Dynamic forest mosaics. Pages 95-160 in: M. L. Hunter, Jr., editor. Maintaining biodiversity in forest ecosystems. Cambridge University Press, Cambridge.
The President's Council on Sustainable Development. 1999. Towards a Sustainable America: Advancing Prosperity, Opportunity, and a Healthy environment for the 21st Century. Washington, DC. 97 pp. plus appendices.
Information for this guide was last updated on: April 7, 2021
Please cite this page as:
New York Natural Heritage Program. 2023.
Online Conservation Guide for
Coastal oak-hickory forest.
Available from: https://guides.nynhp.org/coastal-oak-hickory-forest/.
Accessed September 24, 2023.