Ozark-Ouachita Oak Forest

EVT 7304Ozark-Ouachita Dry-Mesic Oak Forest
CES202.708GNRTreeHardwood
Summary
This system is found throughout the Ozark and Ouachita Highlands ranging to the western edge of the Interior Low Plateau. It is the matrix system of this region and occurs on dry-mesic to mesic, gentle to moderately steep slopes. Soils are typically moderately to well-drained and more fertile than those associated with oak woodlands. A closed canopy of oak species (Quercus rubra and Quercus alba) often associated with hickory species (Carya spp.) typifies this system. Acer saccharum (or Acer floridanum to the south) may occur on more mesic examples of this system. Wind, drought, lightning, and occasional fires can influence this system.
Source: NatureServe Explorer
Vegetation
A closed canopy of oak species (Quercus rubra, Quercus muehlenbergii, and Quercus alba) often associated with hickory species (Carya spp.) typifies this system. Acer saccharum (or Acer floridanum (= Acer barbatum) to the south) may occur in more mesic examples. Some stands in the western edge of the Interior Low Plateau (eastern range limit of the system) may contain Quercus montana (= Quercus prinus). Some other species which may be present include Carex pensylvanica, Carya tomentosa (= Carya alba), Carya cordiformis, Carya glabra, Carya ovata, Cercis canadensis, Cornus florida, Fagus grandifolia, Fraxinus americana, Gleditsia triacanthos, Gymnocladus dioicus, Hybanthus concolor, Juglans nigra, Juniperus virginiana, Lindera benzoin, Liquidambar styraciflua, Maclura pomifera, Ostrya virginiana, Quercus alba, Quercus falcata, Quercus marilandica, Quercus shumardii, Quercus velutina, Schizachyrium scoparium, Smilax spp., Ulmus americana, Ulmus serotina, and Vitis aestivalis.
Source: NatureServe Explorer
Environment
This is the matrix system of this region and occurs on dry-mesic to mesic, gentle to moderately steep slopes. Soils are typically moderately to well-drained and more fertile than those associated with oak woodlands.
Source: NatureServe Explorer
Dynamics
Wind, drought, lightning, and occasional fires can influence this system.
Source: NatureServe Explorer
Distribution
This system is found throughout the Ozark and Ouachita Highlands, reaching to the western Interior Low Plateau of Illinois.
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 floridanum, Acer saccharum, Carya cordiformis, Carya glabra, Carya ovata, Carya tomentosa, Fagus grandifolia, Fraxinus americana, Gleditsia triacanthos, Gymnocladus dioicus, Juglans nigra, Juniperus virginiana, Liquidambar styraciflua, Maclura pomifera, Ostrya virginiana, Quercus alba, Quercus falcata, Quercus muehlenbergii, Quercus prinus, Quercus rubra, Quercus shumardii, Quercus stellata, Quercus velutina, Quercus x macnabiana, Ulmus americana, Ulmus serotina

Tree subcanopy

Cercis canadensis, Cornus florida

Shrub/sapling (tall & short)

Hamamelis vernalis, Lindera benzoin

Herb (field)

Cardamine angustata, Carex pensylvanica, Delphinium newtonianum, Hybanthus concolor, Schizachyrium scoparium, Tradescantia ozarkana, Vitis aestivalis
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.

Mammals (1)

Common NameScientific NameG-Rank
White-footed DeermousePeromyscus leucopusG5

Reptiles (4)

Common NameScientific NameG-Rank
Eastern Hog-nosed SnakeHeterodon platirhinosG5
Coal SkinkPlestiodon anthracinusG5
Eastern Fence LizardSceloporus undulatusG5
Little Brown SkinkScincella lateralisG5
Source: NatureServe Ecological System assessment
At-Risk Species Associated with this Ecosystem (2)

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
Newton's LarkspurDelphinium newtonianumG3--
Ozark SpiderwortTradescantia ozarkanaG3--
Source: NatureServe Ecological System assessment
Component Associations (13)

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 - Quercus muehlenbergii / Cotinus obovatus ForestG2 NatureServe
Juniperus virginiana - Quercus (alba, stellata) - Carya texana WoodlandGNR NatureServe
Liquidambar styraciflua - Quercus (alba, falcata) Ruderal ForestGNA NatureServe
Quercus alba - Carya tomentosa / Ostrya virginiana / Carex pensylvanica - Schizachyrium scoparium WoodlandG3 NatureServe
Quercus alba / Cornus florida Interior Low Plateau ForestG4 NatureServe
Quercus alba - Quercus rubra - Carya tomentosa / Cornus florida Acidic ForestG3 NatureServe
Quercus alba - Quercus velutina - Carya tomentosa / Desmodium nudiflorum Ozark ForestG4 NatureServe
Quercus falcata - Carya tomentosa - Carya ovata ForestG3 NatureServe
Quercus montana / Smilax spp. ForestG4 NatureServe
Quercus muehlenbergii - Quercus shumardii ForestG3 NatureServe
Quercus rubra - Quercus shumardii ForestG3 NatureServe
Quercus velutina - Quercus alba - Carya (glabra, ovata) ForestG4 NatureServe
Vitis aestivalis Vine-ScrubG2 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
ARSNR
ILSNR
MOSNR
OKSNR
Roadless Areas (23)

Inventoried Roadless Areas where this ecosystem is present, identified from LANDFIRE 2024 Existing Vegetation Type spatial analysis. Coverage indicates the proportion of each area occupied by this ecosystem type.

Arkansas (15)

AreaForestCoverageHectares
Richland CreekOzark-St. Francis National Forest92.4%212.31
Hurricane CreekOzark-St. Francis National Forest90.3%835.02
Indian CreekOzark-St. Francis National Forest88.7%2,817.72
Pedestal RocksOzark-St. Francis National Forest85.1%7,565.13
Dismal CreekOzark-St. Francis National Forest83.1%3,080.7
Clifty CanyonOzark-St. Francis National Forest82.4%655.11
Brush HeapOuachita National Forest76.2%1,295.46
Gee CreekOzark-St. Francis National Forest69.1%2,225.79
Devils CanyonOzark-St. Francis National Forest69.1%526.14
PenhookOzark-St. Francis National Forest61.2%1,623.6
East ForkOzark-St. Francis National Forest60.0%3,159.72
Rich Mountain (AR)Ouachita National Forest43.7%457.56
Blue MountainOuachita National Forest36.8%1,454.04
Bear MountainOuachita National Forest23.1%177.66
Little BlakelyOuachita National Forest13.5%182.7

Illinois (1)

AreaForestCoverageHectares
Ripple HollowShawnee National Forest27.3%418.5

Missouri (5)

AreaForestCoverageHectares
Spring Creek Rare II Study AreaMark Twain National Forest75.5%1,496.88
Anderson Mountain Rare II Study AreaMark Twain National Forest62.7%694.8
Swan Creek Rare II Study AreaMark Twain National Forest61.4%1,813.59
Irish Rare II Study AreaMark Twain National Forest60.8%303.3
Big Creek Rare II Study AreaMark Twain National Forest31.1%1,168.74

Oklahoma (2)

AreaForestCoverageHectares
Rich Mountain (OK)Ouachita National Forest42.2%859.05
Beech CreekOuachita National Forest37.9%1,274.4
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.