Great Lakes Limestone Rocky Outcrop

EVT 9116Laurentian-Acadian Calcareous Rocky Outcrop Woodland
CES201.572GNRTreeConifer-hardwood
Summary
This outcrop system occurs in scattered locations from New England west to the Great Lakes. It occurs on ridges or summits of circumneutral to calcareous bedrock. Sites are often exposed and dry; however, there may be local areas of more moist conditions. The vegetation is often a mosaic of woodlands and open glades. This system may also occur on rocks that are primarily acidic but with a local influence of calcium through weathering.
Source: NatureServe Explorer
Distribution
Scattered locations from New England and adjacent Canada west to the eastern Great Lakes.
Source: NatureServe Explorer
Ecologically Associated Plant Species

Plant species that characterize this ecosystem type, organized by vegetation stratum. These are species ecologically associated with the ecosystem, not confirmed present in any specific area.

Tree canopy

Acer saccharum, Fraxinus americana, Thuja occidentalis

Shrub/sapling (tall & short)

Dasiphora fruticosa ssp. floribunda

Herb (field)

Carex eburnea, Clematis occidentalis, Dryopteris fragrans, Oligoneuron album
Source: NatureServe Ecological System assessment
Ecologically Associated Animals (5)

Animal species ecologically associated with this ecosystem type based on NatureServe assessment. These are species whose habitat requirements overlap with this ecosystem, not confirmed present in any specific roadless area.

Reptiles (3)

Common NameScientific NameG-Rank
Ring-necked SnakeDiadophis punctatusG5
Eastern MilksnakeLampropeltis triangulumG5
Common GartersnakeThamnophis sirtalisG5

Butterflies & Moths (2)

Common NameScientific NameG-Rank
Columbine DuskywingErynnis luciliusG3
Columbine Borer MothPapaipema leucostigmaG4G5
Source: NatureServe Ecological System assessment
At-Risk Species Associated with this Ecosystem (1)

Species with conservation concern that are ecologically associated with this ecosystem type. G-Rank indicates global conservation status: G1 (critically imperiled) through G5 (secure). ESA status indicates U.S. Endangered Species Act listing.

Common NameScientific NameG-RankESA Status
Columbine DuskywingErynnis luciliusG3--
Source: NatureServe Ecological System assessment
Component Associations (8)

Plant community associations that occur within this ecological system. Associations are the finest level of the U.S. National Vegetation Classification (USNVC) and describe specific, repeating assemblages of plant species. Each association represents a distinct community type that may be found where this ecosystem occurs.

NameG-Rank
Acer saccharum - Ostrya virginiana - Carya ovata - Quercus rubra Limestone WoodlandG3 NatureServe
Adiantum aleuticum - Asplenium spp. - Cerastium arvense Serpentine Outcrop NatureServe
Juniperus virginiana - Ostrya virginiana / Carex eburnea Woodland NatureServe
Quercus macrocarpa / Danthonia spicata - (Geum triflorum) Alvar Woodland NatureServe
Thuja occidentalis / Carex eburnea Woodland NatureServe
Thuja occidentalis - Fraxinus pennsylvanica / Acer pensylvanicum Woodland NatureServe
Thuja occidentalis / Gaylussacia baccata - Vaccinium angustifolium Woodland NatureServe
Thuja occidentalis / Oligoneuron album Rocky Outcrop NatureServe
State Conservation Ranks (4)

Subnational conservation status ranks (S-ranks) assigned by Natural Heritage Programs in each state where this ecosystem occurs. S1 indicates critically imperiled at the state level, S2 imperiled, S3 vulnerable, S4 apparently secure, and S5 secure. An ecosystem may be globally secure but imperiled in specific states at the edge of its range.

StateS-Rank
MESNR
NHSNR
NYSNR
VTSNR
Methodology and Data Sources

Ecosystem classification: Ecosystems are classified using the LANDFIRE 2024 Existing Vegetation Type (EVT) layer, mapped to NatureServe Terrestrial Ecological Systems via a curated crosswalk. Each EVT is linked to the USNVC (U.S. National Vegetation Classification) hierarchy through pixel-level co-occurrence analysis of LANDFIRE EVT and NatureServe IVC Group rasters across all roadless areas.

Vegetation coverage: Coverage percentages and hectares are derived from zonal statistics of the LANDFIRE 2024 EVT raster intersected with roadless area boundaries.

Ecosystem narratives and community species: Sourced from the NatureServe Explorer API, representing professional ecological assessments of vegetation composition, environmental setting, dynamics, threats, and characteristic species assemblages.

IVC hierarchy: The International Vegetation Classification hierarchy is sourced from the USNVC v3.0 Catalog, providing the full classification from Biome through Association levels.

Component associations: Plant community associations listed as components of each NatureServe Ecological System. Association data from the NatureServe Explorer API.

State ranks: Conservation status ranks assigned by NatureServe member programs in each state where the ecosystem occurs.