Calcareous pavement woodlands are underlain by limestone bedrock. Limestone refers to rock formed mostly of calcium carbonate, but to geologists, limestone is only one of several types of "carbonate rocks." These rocks are composed of more than 50% carbonate minerals, generally the minerals calcite or dolomite (calcium-magnesium carbonate) or both.
There are probably much less than 50 occurrences statewide. A few documented occurrences have good viability and several are protected on public land or private conservation land. This community is limited to the calcareous regions of the state, and there are only a few high quality examples. The current trend of this community is probably stable for occurrences on public land and private conservation land, or declining slightly elsewhere due to moderate threats that include conversion to pastureland, development, trampling by visitors, ATVs, and invasive species.
The number and acreage of calcareous pavement woodlands in New York have probably declined slightly in recent decades as a result of development, conversion to pastureland, recreational ATVs, and invasive species.
The number and acreage of calcareous pavement woodlands in New York have probably declined moderately to substantially from historical numbers likely correlated with past conversion to pastureland.
Calcareous pavement woodlands are threatened by development (e.g., conversion to agricultural uses such as pastureland, residential, industrial), either directly within the community or in the surrounding landscape. Other threats include habitat alteration (e.g., road crossings, intensive cedar logging, mining) and relatively minor recreational overuse (e.g., ATVs, trampling by visitors, trash dumping). Deer overbrowsing may be a threat at a few sites. Several calcareous pavement barrens are threatened by invasive species, such as black swallow-wort (Cynanchum louiseae), Morrow's honeysuckle (Lonicera morrowii), and buckthorn (Rhamnus cathartica).
Increase and/or maintain the size of existing calcareous pavement woodlands by increasing patch size where appropriate, by "softening" the abrupt forest edges by maintaining a native shrub transition zone. Improve the condition of existing calcareous pavement barrens by reducing and/or eliminating invasive species, such as black swallow-wort (Cynanchum louiseae), Morrow's honeysuckle (Lonicera morrowii), and buckthorn (Rhamnus cathartica). Improve barrens by minimizing trail network and clearly marking existing trails, and developing and implementing a prescribed burn plan at appropriate sites. Improve the landscape context of the barrens by encouraging surrounding landowners to establish natural buffers and restore natural corridors to other larger natural landscape blocks.
A natural (usually forested) buffer around the edges of this community will help it maintain the microclimatic characteristics that help make this community unique.
Survey for occurrences statewide to advance documentation and classification of calcareous pavement woodlands. Continue searching for large sites in excellent to good condition (A- to AB-ranked). Periodic inventory of the calcareous pavement woodlands is needed, in order to keep occurrence data current.
Research the composition of calcareous pavement woodlands statewide in order to characterize variations.
The best sites are concentrated in the St. Lawrence Glacial Lake Plain Subsection of the St. Lawrence (non-alvar areas) and Champlain Valley Ecoregion. Other examples are located in the Eastern Ontario Lake Plain, the St. Lawrence Glacial Marine Plain, and Champlain Glacial Lake and Marine Plain. Additional small sites occur along the Onondaga Escarpment and the Helderberg Highlands.
The range is estimated to span north to southern Ontario, west to northern Michigan, south to the Helderburg Highlands of central New York and east to the Lake Champlain Valley of New York and Vermont.
The tree canopy layer is sparse and often grows in clumps. Characteristic trees include northern white cedar (Thuja occidentalis), eastern red cedar (Juniperus virginiana), hop hornbeam (Ostrya virginiana), bur oak (Quercus macrocarpa), white ash (Fraxinus americana), red maple (Acer rubrum), and white pine (Pinus strobus). Characteristic shrubs include seedlings and saplings of trees listed above plus shrubby dogwoods (Cornus racemosa, C. amomum), common juniper (Juniperus communis), fragrant sumac (Rhus aromatica), and prickly ash (Zanthoxylum americanum). Characteristic herbs include a mix of native and non-native species including Canada bluegrass (Poa compressa), poverty-grass (Danthonia spicata), gray goldenrod (Solidago nemoralis), panic grasses (Panicum flexile, Dichanthelium acuminatum), prairie fleabane (Erigeron strigosus var. strigosus), American pennyroyal (Hedeoma pulegioides), balsam ragwort (Packera paupercula), Queen-Anne's-lace (Daucus carota), hawkweeds (Hieracium spp.), clovers (Trifolium spp.), ebony sedge (Carex eburnea), upland white aster (Oligoneuron album), herb robert (Geranium robertianum), and wild strawberry (Fragaria virginiana). Fruticose and foliose lichens are locally common in the grassy areas, including reindeer lichens (Cladonia spp.) and cup lichen (Cladonia pocillum). Characteristic mosses include hair cap moss (Polytrichum spp.) and Tortella tortuosa.
This community is an open canopy woodland that occurs on very shallow soils over flat, striated outcrops of calcareous bedrock (limestone and dolomite). This community includes patches of sparsely vegetated rock rubble in between dense cedar clumps or grassy open areas. This woodland is not typically found in an alvar ecosystem, but is often associated with limestone woodlands.
Known examples of this community have been found at elevations between 130 feet and 320 feet.
Calcareous pavement woodlands offer a nice array of spring ephemerals and early wildflowers from May to June.
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.
Percent cover
This figure helps visualize the structure and "look" or "feel" of a typical Calcareous Pavement Woodland. 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%.
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.
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.
This guide was authored by: Gregory J. Edinger
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
Calcareous pavement woodland.
Available from: https://guides.nynhp.org/calcareous-pavement-woodland/.
Accessed October 3, 2023.