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Ecological site F136XY400NC

Triassic Basin Upland Woodland, Expansive Clay, Seasonally Wet and Dry

Last updated: 5/02/2025
Accessed: 10/13/2026

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General information

Provisional. A provisional ecological site description has undergone quality control and quality assurance review. It contains a working state and transition model and enough information to identify the ecological site.

MLRA notes

Major Land Resource Area (MLRA): 136X–Southern Piedmont

This MLRA is on a large piedmont underlain by metamorphic and igneous bedrock. It stretches from north-central Virginia to east-central Alabama, running parallel to the Appalachian highlands to the northwest and the Atlantic coast to the southeast.

MLRA 136 has only subtle climatic differences with MLRA 148 (Northern Piedmont), with which it shares a common geologic origin. This adjacent MLRA sits to the north. Along the fall line, it shares a boundary with MLRA 133A (Southern Coastal Plain), MLRA 137 (Carolina and Georgia Sand Hills), and 133C (Gulf Coastal Plain). Here, unconsolidated Coastal Plain sediments intersect the much older Piedmont bedrock. Along it's northwestern boundary, it sits adjacent to MLRAs 130B (Southern Blue Ridge), 130A (Northern Blue Ridge), and 128 (Southern Appalachian Ridges and Valleys). These MLRAs are distinguished from the Southern Piedmont by topographic and elevational differences, as well as differences in the age, origin, and degree of metamorphism of the underlying bedrock.

Five states are intersected by the MLRA, including North Carolina (29 percent), Georgia (27 percent), Virginia (20 percent), South Carolina (17 percent), and Alabama (7 percent). The MLRA extent makes up about 63,720 square miles (165,034 square kilometers).

MLRA PHYSIOGRAPHY
The landscape is generally rolling to hilly, with a well-defined drainage pattern. Streams have dissected the original Piedmont plateau, forming narrow ridgetops, somewhat broad interfluves, and short, steep side slopes adjacent to the streams and drainageways. With some exceptions, the valley floors are generally narrow and make up about 10 percent or less of the land area. The associated stream terraces are generally small and of minor extent.

The landscape is moderately dissected overall, with isolated erosional remnants (monadnocks) and other areas of high topographic relief interspersed. Over most of the MLRA, elevation ranges from approximately 325 to 1,315 feet (100 to 400 meters), with elevations generally increasing toward the Appalachian Highlands, in the upper Piedmont, and decreasing toward the Coastal Plain, in the lower Piedmont.

The major rivers that cross this area en route to the ocean include, from north to south, the James, Roanoke, Cape Fear, Savannah, Altamaha, Chattahoochee, and Alabama Rivers. These rivers typically originate within the Piedmont or in the Blue Ridge. They flow east and south across the Coastal Plain and empty into the Atlantic Ocean or the Gulf of America.

MLRA GEOLOGY
Precambrian and Paleozoic metamorphic and igneous rocks underlie almost all of this MLRA. The dominant metamorphic rock types include gneiss, schist, slate, argillite, and phyllite, among others. Dominant igneous rock types include granite and other related felsic crystalline rocks. Mafic intrusive rocks, including gabbro, diabase, amphibolite, and other dark colored rocks, underlie a minority of the upland landscape. These mafic intrusions crop out in the form of dikes and sills, and often weather to produce soils high in base cations.

The Carolina Slate Belt runs lengthwise through the east-central part of the MLRA, in southern Virginia, North Carolina, South Carolina, and the eastern-most part of the Georgia Piedmont. This region is underlain by fine-grained metasedimentary and metavolcanic rock, which generally weathers to produce soils high in silt.

From Virginia to North Carolina, and in a single county in South Carolina, fault-bounded Triassic Basins are scattered amongst the igneous and metamorphic uplands. These basins are underlain by Triassic and Jurassic siltstone, shale, sandstone, and mudstone, which were laid down in response to continental rifting and subsequent erosion during the Mesozoic era.

MLRA SOILS
The dominant soil orders of the MLRA are Ultisols, Inceptisols, and Alfisols. Ultisols and Alfisols are typically found on more stable landforms, such as interfluves, gentle hillslopes, broad ridgetops, and stream terraces, while Inceptisols are typically found on less stable landforms, including flood plains, steep hillslopes, and narrow ridgetops.

Soils of the region predominantly have a thermic temperature regime, a udic moisture regime, and generally have kaolinitic or mixed mineralogy. In the upper Piedmont of Virginia and North Carolina however, soils have a mesic soil temperature regime, as depicted in figure 2. The mesic soil temperature regime portion of the MLRA is oriented from northeast to southwest and occupies approximately 18 percent of the MLRA extent, or 11,729 square miles (30,377 square kilometers).

Broadly speaking, soils of the Southern Piedmont uplands are shallow to very deep, well drained, and loamy or clayey. Soils of the river valleys are generally very deep, well to poorly drained, and loamy. Soils tend to be finer-textured than in Coastal Plain regions.

MLRA CLIMATE
In general, precipitation is evenly distributed throughout the year in this MLRA, with occasional drought-like conditions extending from late summer into autumn. During the growing season, most of the rainfall comes from high-intensity, convective thunderstorms. Significant moisture also comes from the movement of warm and cold fronts across the MLRA from November to April. High amounts of rain can also occur during hurricanes, usually during the months of August through October.

Over most of the MLRA, snowfall is typically light, though overall, the mesic soil temperature regime portion of the MLRA features colder temperatures, more snowfall, and a shorter growing season than in the thermic portion. The cooler climate in this region supports an increase in species with northern or Blue Ridge affinities. Both the mean annual temperature and the length of the freeze-free period increase from north to south and with decreasing elevation from the upper to the lower Piedmont.

MLRA LAND USE AND RESOURCES
Once largely cultivated, much of this region is now planted to loblolly pine or has reverted to successional pine and hardwood forests. The more productive lands support small to medium-size family farms that produce crops and livestock, while the less productive lands have been in forest for some time. Most of the open areas are used for grazing beef cattle, though in years past, dairy cattle were also important to the local economy. The principal crops of the region include corn, soybeans, and small grains. Burley tobacco remains a crop of local importance. Cotton is grown in the thermic soil temperature regime portion of the MLRA.

Several major land cover transformations have occurred in the Southern Piedmont over the past several centuries; from open woodlands sculpted by fire, to farmland, to closed forests and planted pine, past land uses have played an outsized role in shaping present-day soils and vegetation patterns in the region. Land-use intensity peaked with the arrival of the industrial revolution, which gradually increased demand for textiles. Cotton became the dominant crop over much of the region.

In spite of early successes, two centuries of poor management practices accelerated soil erosion, stripping away the fertility and moisture-supplying capacity of soils. In addition to soil losses in the uplands, legacy sediments derived from the eroded land rapidly accumulated in the river valleys below, often leading to changes in hydrology and flooding frequency.

After being stripped of it's loamy topsoil, many areas of the Piedmont had been so badly eroded as to render the land unsuitable or economically impractical for agriculture. The effects of erosion were widespread, with cumulative soil loss estimates ranging from 5 to 10 inches on average. The steeper slopes, which had often been cleared and farmed at the height of the Cotton era, generally suffered greater losses. By the 1930's, crop production was in rapid decline in the Southern Piedmont. The loss of soil productivity due to erosion, losses to the cotton boll weevil, development of synthetic fibers, and the onset of the Great Depression all contributed to rapid abandonment of cropland. By 1960, cropland acres had decreased by more than 50 percent in nearly every county in the Southern Piedmont.

While crop production is still important today on the more productive lands, those of lower productivity, or those that were subject to severe erosion, were often abandoned some time ago. Typically, they have either reverted to forest, or have been converted to other uses. Although the productivity of soils was greatly reduced through erosion, less intensive land uses such as grazing and forestry were still feasible. These land uses gained popularity as patterns of urban migration, low commodity prices, and other factors gradually made crop production less economical on the marginal lands.

In recent years, large-scale adoption of soil conservation practices have led to better outcomes with respect to erosion in much of MLRA, increasing the economic viability and long-term sustainability of Piedmont farms. Despite some success, water erosion remains one of the most important soil resource concerns in the MLRA.

Other major resource concerns include increasing conversion of prime farmland and farmland of statewide importance to urban uses. Throughout the MLRA, metropolitan areas are expanding into lands that have historically been used for timber or agriculture. This change in land use is occurring rapidly in the corridor called the Piedmont Crescent, which extends from Atlanta, Georgia, to Raleigh, North Carolina.

HISTORIC VEGETATION COVER
Over most of the Southern Piedmont uplands, the historic oak-hickory, or oak-hickory-pine forest, once covered large portions of the landscape. It was dominated by upland oaks, such as white oak (Quercus alba), northern red oak (Quercus rubra), and southern red oak (Quercus falcata), with a smaller contribution from hickories (Carya spp.) and pines. The principal pine species are shortleaf pine (Pinus echinata), loblolly pine (Pinus taeda), and to the north and west, Virginia pine (Pinus virginiana). In the southernmost and easternmost portions of the MLRA, the historic montane longleaf pine forest, dominated by longleaf pine (Pinus palustris), shortleaf pine (P. echinata), and dry-site oaks, was found on ridgetops and steep south or west-facing slopes.

According to historic accounts, forests and woodlands of the past were generally more open and park-like, having been exposed to a more frequent fire regime. Piedmont prairies, likely maintained by Native Americans, were also reportedly common across the landscape, as were fire-maintained canebrakes along the streams (Trimble 1974; Daniels 1987; Griffith et al. 2002; Van Lear et al. 2004; Dearman and James 2019; Schomberg et al. 2020; USDA-NRCS 2022).

LRU notes

MLRA 136 is one of the largest MLRAs in the United States. It has a broad north-south and east-west extent and covers a wide range of elevations. The MLRA is partitioned by the mesic-thermic line, which divides the MLRA into mesic and thermic soil temperature regimes (figure 2.). The mesic soil temperature regime was delineated based on estimates of the native range of loblolly pine, which was historically absent in this part of the MLRA. In addition, this region is said to represent the northern and western limits of cotton production, an important crop to the south and east.

This ecological site is associated with EPA ecoregion 45g (Triassic Basins) of the northern part of the MLRA, of which approximately 80 percent of the area is in the thermic soil temperature regime. Fieldwork will be needed to determine if additional ecological site concepts will be needed to cover the remaining soils that fall within the mesic soil temperature regime portion of the MLRA.

The Triassic Basins of the southeastern United States are arranged in several discontinuous narrow bands, oriented toward the northeast. They have unusual Piedmont geology of unmetamorphosed shales, sandstones, mudstones, siltstones, and conglomerates. Elevation and topographic relief are considerably lower than in surrounding regions. Stream valleys that cross the Triassic Basins tend to be broad, being underlain by rocks that are more easily eroded. Streams that cross the adjacent Carolina Slate Belt or felsic crystalline terrain have narrower valleys, which widen abruptly upon entering the Triassic Basins. Soils in this region tend to be clayey, with low permeability, though sandier soils weathered from sandstone also occur. The clay fraction in some soils can have a high shrink-swell potential which can hinder construction. Land cover consists of a mosaic of mixed hardwood forests, mixed pine-hardwood woodlands, cutover land, pasture, cropland, and urban land (Daniels et al. 1999; Griffith et al. 2002).

Classification relationships

APPLICABLE USNVC ASSOCIATIONS
CEGL003714 Quercus stellata - Quercus marilandica - Carya (carolinae-septentrionalis, glabra) / Schizachyrium scoparium; CEGL004037 Quercus phellos - Quercus (alba, stellata) - Carya carolinae-septentrionalis; CEGL004413 Quercus stellata - (Quercus marilandica) / Gaylussacia frondosa

APPLICABLE EPA ECOREGIONS
Level III: 45. Piedmont
Level IV: 45g. Triassic Basins (EPA 2013).

APPLICABLE USFS ECOLOGICAL UNITS
Domain: Humid Temperate
Division: Subtropical
Ecological province: 231. Southeastern Mixed Forest
Ecological sections: 231I.Central Appalachian Piedmont (Cleland et al. 2007).

Based on the USGS physiographic classification system (Fenneman and Johnson 1946), most of MLRA 136 is in the Piedmont Upland section of the Piedmont province, in the Appalachian Highlands division.

Ecological site concept

This ecological site includes seasonally wet and seasonally dry soils of Triassic Basin uplands, in the northern part of the MLRA, on broad interfluves and gentle hillslopes. This ecological site is subject to wetting and drying cycles typical of "hydroxeric" conditions, due primarily to shrink-swell clay minerology and low relief.

Soils on this ecological site are typically somewhat poorly to moderately well drained Alfisols or Ultisols, which formed in sedimentary rocks of Triassic age. These soils tend to be more acidic than similar soils weathered from mafic intrusive rock. The subsoil has a high clay content and the clay fraction is typically dominated by 2:1 clay minerals.

A transient water table is present within 12 to 40 inches of the soil surface during the cooler months. Still, these wet conditions are temporary and in most instances the influence of dry edaphic conditions, which develop over the course of the growing season, are reflected in the character of the vegetation.

The reference state supports an open to partially open canopy woodland with an understory dominated by generalists and acid-loving plant species, usually lacking the stronger basic indicator species typical of mafic substrates. Important canopy species include post oak (Quercus stellata), blackjack oak (Quercus marilandica), willow oak (Quercus phellos), and several species of hickory (Carya spp.). Dominant land uses include pasture and hayland, cropland, planted pine, and wildlife habitat. Soils are poorly-suited to most building applications or septic system installations because of seasonal wetness and shrink-swell hazard.

ES CHARACTERISTICS SUMMARY
• Occurs on Piedmont uplands, on broad interfluves, upland flats, and gentle hillslopes in the Triassic Basins of the northern part of the MLRA
• Parent materials: Triassic sedimentary rock
• Seasonal high water table: perched, 12 - 40 inches from the soil surface
• Subsoil layers have a high to very high shrink-swell potential
• The clay fraction is dominated by 2:1 clay minerals
• Soils: moderately deep to very deep, moderately well drained to somewhat poorly drained Alfisols or Ultisols

Associated sites

F136XY410NC	Triassic Basin Upland Forest, Seasonally Wet Found in similar landscape positions, but soils have a lower shrink-swell potential. Fluctuations in plant available water are not as pronounced. Dry-site species, such as post oak (Quercus stellata) are generally scarce or absent.
F136XY420NC	Triassic Basin Upland Forest, Moist Generally found in slightly higher landscape positions. The seasonal high water table is deeper (≥ 40 inches from the soil surface, usually deeper). The clay fraction is not dominated by 2:1 clay minerals. Moisture-loving plant species typically increase in abundance, of which northern red oak (Quercus rubra) is most notable.
F136XY430NC	Triassic Basin Upland Forest, Dry Usually found in higher landscape positions on narrow ridges and steep hillslopes. A seasonal high water table is usually absent within 72 inches of the soil surface. Depth to bedrock is generally shallower and soils have higher permeability. Species tolerant of anaerobic conditions, such as willow oak (Quercus phellos), are typically absent.
F136XY710NC	Basic Upland Woodland, Expansive Clay, Seasonally Wet and Dry Associated with mafic dikes and sills scattered over the Triassic Basins. In similar landscape positions and with a similar relative moisture status. Soil properties are similar, but soil pH is typically higher, supporting a diverse suite of basic indicator species in the understory.

Similar sites

F136XY710NC	Basic Upland Woodland, Expansive Clay, Seasonally Wet and Dry Soil properties are similar, but parent materials are Triassic sedimentary rock. Soil pH is typically higher, increasing cover from basic indicator species in the understory.

F136XY710NC

Basic Upland Woodland, Expansive Clay, Seasonally Wet and Dry

Soil properties are similar, but parent materials are Triassic sedimentary rock. Soil pH is typically higher, increasing cover from basic indicator species in the understory.

Figure 1. EPA level IV ecoregions of the Southern Piedmont (45).

Figure 2. View of the Southern Piedmont Major Land Resource Area with a focus on Triassic Basins, including the Deep River, Dan River-Danville, Richmond, Davie, Farmville, Scottsville, and Taylorsville basins.

Figure 3. Spatial illustration of soil temperature regimes of the Southern Piedmont.

Figure 4. Spatial extent of this ecological site representing the major areas where this site is important on the landscape.

Table 5. Dominant plant species

Tree	(1) Quercus stellata (2) Quercus marilandica
Shrub	(1) Vaccinium (2) Gaylussacia
Herbaceous	(1) Schizachyrium scoparium (2) Pteridium aquilinum

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Physiographic features

This ecological site is found on broad interfluves and gentle slopes, in the Triassic Basins of Virginia, North Carolina, and a small portion of South Carolina, in EPA ecoregion 45g. The geologic substrate is derived from sedimentary rocks of Triassic age. Representative locations are gently sloping to moderately steep, with a representative slope of 2 to 10 percent and a maximum slope of 20 percent.

GENERAL TRIASSIC BASIN GEOMORPHOLOGY
The landscape of Triassic Basins consists of irregular plains with low rounded hills, gentle ridges, and shallow, but broad river valleys. These sedimentary basins are bounded by faults, formed through continental extension, or rifting. In the Southern Piedmont, these rift basins are scattered throughout the northern part of the MLRA, from the South Carolina-North Carolina state line, to just south of Charlottesville and Richmond, Virginia.

In eastern North America, Triassic Basins formed during continental extension associated with the separation of North America and Africa during the first half of the Mesozoic era. In the process of rifting, the ground between the faults dropped down, later filling with sediments eroded off the Appalachian highlands. The material hardened into various sedimentary rock types, including siltstone, shale, sandstone, mudstone, or conglomerate. These rocks are younger and tend to be softer than the igneous and metamorphic rocks that characterize most of the MLRA.

In the Southern Piedmont, the landscape of Triassic Basins is one of lower overall elevation and topographic relief than the surrounding uplands. Where the easily eroded Triassic sediments meet the surrounding Piedmont uplands, steep escarpments have often been cut as a result of differential erosion. Other than these outlying slopes, only the Dan River-Danville basin contains noteworthy topography, including a system of low ridges that run the length of the basin, rising approximately 200 to 300 feet from the basin floor (Hall and Boyer 1992; Schlische 1993; Daniels et al. 1999; Woods et al. 1999; Griffith et al. 2002; EPA 2011; USDA-NRCS 2022).

Table 6. Representative physiographic features

Hillslope profile	(1) Backslope (2) Shoulder (3) Summit
Landforms	(1) Piedmont > Hillslope (2) Piedmont > Interfluve
Runoff class	High to very high
Flooding frequency	None
Ponding frequency	None
Elevation	240 – 680 ft
Slope	2 – 10 %
Water table depth	18 – 30 in
Aspect	Aspect is not a significant factor

Table 7. Representative physiographic features (actual ranges)

Runoff class	Medium to very high
Flooding frequency	None
Ponding frequency	None
Elevation	230 – 790 ft
Slope	2 – 20 %
Water table depth	12 – 40 in

Climatic features

On this ecological site, the average mean annual precipitation is 46 inches. On average, the rainiest months occur from July through September, as well as in March. The driest months occur from October through February, in addition to April.

Table 8 Representative climatic features

Frost-free period (characteristic range)	180-200 days
Freeze-free period (characteristic range)	210-230 days
Precipitation total (characteristic range)	50-50 in
Frost-free period (actual range)	170-200 days
Freeze-free period (actual range)	190-230 days
Precipitation total (actual range)	40-50 in
Frost-free period (average)	180 days
Freeze-free period (average)	220 days
Precipitation total (average)	50 in

Characteristic range

Actual range

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Figure 1. Monthly precipitation range

Characteristic range

Actual range

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Figure 2. Monthly minimum temperature range

Characteristic range

Actual range

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Figure 3. Monthly maximum temperature range

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Figure 4. Monthly average minimum and maximum temperature

Figure 5. Annual precipitation pattern

Figure 6 Annual average temperature pattern

Climate stations used

(1) WADESBORO [USC00318964], Wadesboro, NC
(2) SANFORD 8 NE [USC00317656], Sanford, NC
(3) RALEIGH DURHAM INTL AP [USW00013722], Raleigh, NC
(4) DURHAM [USC00312515], Durham, NC
(5) OXFORD 1 E [USC00316507], Oxford, NC
(6) DANVILLE [USC00442245], Danville, VA
(7) AMELIA 8 NE [USC00440188], Amelia Court House, VA
(8) APEX [USC00310212], Apex, NC
(9) PAGELAND [USC00386616], Pageland, SC
(10) CARY [USC00311535], Cary, NC
(11) FALLS LAKE [USC00312993], Raleigh, NC
(12) OXFORD AG [USC00316510], Oxford, NC

Soil features

Soils on this ecological site are typically moderately deep to very deep, moderately well drained to somewhat poorly drained Alfisols or Ultisols. Parent materials are residuum derived from Triassic sedimentary rock, such as Triassic shale, siltstone, or mudstone.

Soils associated with this ecological site generally have a subsoil with a high clay content and are typically in a fine particle size family. In representative pedons, subsoil layers have a very plastic, very sticky, and very firm consistence. The clay fraction is dominated by 2:1 clay minerals, namely montmorillonite or others in the smectite group. Slickensides are a common feature. Subsoil layers have a high to very high shrink-swell potential, with a minimum linear extensibility of 6 percent. Partially weathered sedimentary rock is often close to the surface, commonly within 60 inches or less of the soil surface. In contrast to similar soils associated with mafic intrusive rock, reaction in the subsoil is typically strongly to very strongly acid (pH 4.5 to 5.5). In the surface layers, reaction varies with land use and management. Under low input or forested conditions, it generally falls somewhere between pH 4.5 and 6.

As a result of their clay minerology, soils on this ecological site are subject to distinct wetting and drying cycles, fluctuations in plant available water, and seasonal periods of soil saturation and anaerobic conditions. Soils dominated by 2:1 clay minerals can store large volumes of water at field capacity. Soil water content can remain high for extended periods, typically during the winter and early spring. However, these clay minerals also hold on to water more tightly when they do dry out, leaving little water available to plants during dry periods. The result is a water availability dynamic that alternates between being saturated and anaerobic during the cooler months, to being thoroughly parched during warm-season dry spells (Buol et al. 2011).

Soils on this ecological site have a seasonal high water table between 12 and 40 inches of the mineral soil surface. The perched water table persists for periods long enough to leave behind redoximorphic features indicative of anaerobic conditions (i.e., iron and manganese depletions). Still, these wet conditions are temporary and in most instances the influence of dry edaphic conditions, which develop over the course of the growing season, are reflected in the character of the vegetation.

Modal soil taxa include: Oxyaquic Vertic Hapludalfs
Modal soil series include: White Store, Polkton
Other soils attributed to this ecological site include Green Level, Wolftrap, Easthamlet, and Carbonton.

Note: soils included in this ecological site concept are associated with the Triassic Basins of the northern part of the MLRA, in both the thermic and mesic soil temperature regime portions of the MLRA. A significant majority of the land area (approximately 80 percent) falls within the thermic portion of the MLRA, as the Triassic Basins near the fall line are considerably larger in area. Fieldwork will be needed to quantify expected differences in species composition, or other potential distinctions, to determine if an equivalent ecological site concept exclusive to the mesic soil temperature regime is warranted.

An illustration of a soil profiles belonging to the Polkton and White Store series, representative soil series associated with this ecological site, differentiated by the depth to bedrock.

Figure 7. An illustration of a soil profiles belonging to the Polkton and White Store series, representative soil series associated with this ecological site, differentiated by the depth to bedrock.

Figure 8. A soil profile of the Polkton series.

Table 9. Representative soil features

Parent material	(1) Residuum – sedimentary rock
Surface texture	(1) Loam (2) Silt loam (3) Fine sandy loam (4) Sandy loam
Drainage class	Somewhat poorly drained to moderately well drained
Permeability class	Very slow
Depth to restrictive layer	34 – 56 in
Soil depth	34 – 56 in
Surface fragment cover <=3"	Not specified
Surface fragment cover >3"	Not specified
Available water capacity (0-80in)	5 – 9 in
Sodium adsorption ratio (0-40in)	0 – 1
Soil reaction (1:1 water) (0-10in)	4.5 – 6
Subsurface fragment volume <=3" (0-80in)	0 – 7 %
Subsurface fragment volume >3" (0-80in)	0 – 1 %

Table 10. Representative soil features (actual values)

Drainage class	Somewhat poorly drained to moderately well drained
Permeability class	Very slow to moderately slow
Depth to restrictive layer	28 – 999 in
Soil depth	28 – 80 in
Surface fragment cover <=3"	0 %
Surface fragment cover >3"	0 %
Available water capacity (0-80in)	4 – 10 in
Sodium adsorption ratio (0-40in)	0 – 4
Soil reaction (1:1 water) (0-10in)	3.5 – 6.5
Subsurface fragment volume <=3" (0-80in)	0 – 13 %
Subsurface fragment volume >3" (0-80in)	0 – 2 %

Ecological dynamics

U.S. National Vegetation Classification (USNVC) associations that are consistent with reference conditions on this ecological site include CEGL003714 Quercus stellata - Quercus marilandica - Carya (carolinae-septentrionalis, glabra) / Schizachyrium scoparium. Under slightly wetter site conditions, CEGL004037 Quercus phellos - Quercus (alba, stellata) - Carya carolinae-septentrionalis may be more representative. Both of these concepts are closely related to the reference community, though they are likely not entirely representative, as they target examples over mafic substrates. Some overlap is apparent with CEGL004413 Quercus stellata - (Quercus marilandica) / Gaylussacia frondosa, an association representing similar woodlands over felsic crystalline or metasedimentary substrates (USNVC 2022).

This ecological site is subject to wetting and drying cycles typical of "hydroxeric" conditions. These conditions include seasonal extremes in plant available water, caused primarily by shrink-swell clay minerology and low relief. The shrinking and swelling properties are responsible for fluctuating soil water potentials and cause shearing of the fine roots of woody plants. Layers of dense, plastic clays, which sit below the surface, can behave somewhat like rock, inhibiting root development, perching or ponding water during wet cycles, while simultaneously limiting the infiltration of water, contributing to dry cycles. These edaphic factors produce a characteristically stunted canopy and create favorable conditions for recurring fires which would have historically helped maintain an open woodland structure.

The landscape of the Triassic Basins is one of lower overall elevation and topographic relief than the surrounding uplands. Because of the ease with which the land could be cleared and cultivated, most of the arable land was put into production early on during European settlement of the Piedmont. Cotton and tobacco were the principle crops. By the turn of the twentieth century, very little remained of the original forest cover, though large-scale abandonment of cropland agriculture began a few decades later. Today most of the forest cover in the Triassic Basin uplands is in a state of young secondary growth, consisting of stands dominated by loblolly pine (Pinus taeda), shortleaf pine (P. echinata), or Virginia pine (P. virginiana), with opportunistic hardwoods and seedlings of oaks and hickories in the understory or interspersed in the canopy. The remainder is being used for pasture, managed pine plantations, and urban development. The most productive lands are still under cultivation. In young stands, the importance of Virginia pine increases gradually to the north and west, while loblolly pine is favored toward the south and east.

MATURE FORESTS
The reference state typically has an open to partially open structure, featuring stunted dry-site oaks such as post oak (Quercus stellata) and blackjack oak (Quercus marilandica), a lesser proportion of hickories (e.g., Carya glabra, C. tomentosa, C. carolinae-septentrionalis), and scattered shortleaf pines (Pinus echinata). White oak (Quercus alba) is consistent in the canopy, but is usually a minor species.

On the wetter end of the range of variability, site conditions often support a higher cover of willow oak (Quercus phellos), which may be codominant. These wetter variants generally have a lower cover of blackjack oak (Q. marilandica).

Shrink-swell soils of the Triassic Basin uplands are more acidic than similar soils that formed in mafic intrusive rock. For this reason, generalists and acid-loving species make a higher contribution to the the subcanopy, shrub, and herb layers, while strong basic indicator species typical of mafic substrates are usually scarce. Important species of the subcanopy layer include blackgum (Nyssa sylvatica), flowering dogwood (Cornus florida), common persimmon (Diospyros virginiana), eastern redcedar (Juniperus virginiana), eastern redbud (Cercis canadensis), and winged elm (Ulmus alata).

Characteristic species of the shrub layer include several species of blueberry (Vaccinium spp.), huckleberry (Gaylussacia spp.), Carolina rose (Rosa carolina), St. Andrew's cross (Hypericum hypericoides ssp. multicaule), and arrowwood (Viburnum spp.).

DYNAMICS OF NATURAL SUCCESSION AND FIRE ECOLOGY
Beginning in the early 20th century, a widespread fire suppression campaign resulted in a dramatic decrease in the frequency of fires across the Southeast. These changes gradually altered the vegetation structure and species composition of ecosystems that were dependent on fire for seedling recruitment, reproduction, and maintenance.

On this ecological site, the partially open canopy structure seen in some remnant examples is maintained, at least in part, by extremes in plant water availability. Few tree species are tolerant of alternating periods of soil saturation and the extremely dry soil conditions which develop during the growing season. Further, herbaceous plants are more tolerant of shrinking and swelling cycles that lead to shearing of the fine roots. Still, the natural fire regime would have produced a much more open canopy and understory than is seen in most examples presently, and promoted a dense herbaceous layer that could efficiently carry fire in future burns.

Because these communities are predominantly small-patch and spatially insular, fires would have spread primarily from the surrounding landscape. In all likelihood, the fire return interval would have largely matched that of the surrounding forests. However, because of extreme fluctuations in soil moisture, the effects of fire would have been greater, presumably maintaining a more open woodland structure than is seen presently. With a dense grassy herb layer, burning would have been more complete and fire more intense than in the current hardwood litter. Under a more regular fire regime, pyrophytic oaks, pines, and other fire-dependent plant species are more competitive. Under these conditions, tree replacement would presumably be less dependent on canopy gaps and more on fire than under fire-suppressed conditions, or compared to the more prevalent oak-hickory forests of the surrounding landscape.

A combination of prescribed burns and selective removals can open up the understory and constrain the growth of fire-intolerant opportunistic species, thereby restoring the health and vigor of forests that evolved under a more regular fire regime (Pinchot and Ashe 1897; Peet and Christensen 1980; Schafale and Weakley 1990; Schwartz et al. 2007; Spira 2011; Guyette et al. 2012; Schafale 2012a, 2012b; Vander Yacht et al. 2020; Fleming et al. 2021; Greenberg et al. 2021; Spooner et al. 2021).

SPECIES LIST
Canopy layer: Quercus stellata, Quercus marilandica, Pinus echinata, Quercus alba, Quercus phellos, Carya tomentosa, Carya glabra, Carya carolinae-septentrionalis, Pinus taeda, Quercus falcata, Quercus velutina

Subcanopy layer: Nyssa sylvatica, Cornus florida, Diospyros virginiana, Juniperus virginiana, Cercis canadensis, Ulmus alata, Chionanthus virginicus, Liquidambar styraciflua, Acer rubrum, Fraxinus americana, Ilex opaca

Shrub layer: Vaccinium stamineum, Vaccinium arboreum, Vaccinium tenellum, Vaccinium pallidum, Vaccinium fuscatum, Viburnum rafinesqueanum, Gaylussacia frondosa, Gaylussacia baccata, Rosa carolina, Hypericum hypericoides ssp. multicaule, Ceanothus americanus, Viburnum rufidulum, Elaeagnus umbellata (I)

Vines/lianas: Smilax rotundifolia, Smilax glauca, Smilax bona-nox, Vitis rotundifolia, Campsis radicans, Smilax bona-nox, Parthenocissus quinquefolia, Lonicera sempervirens, Loncera japonica (I.),

Herb layer - forbs: Pteridium aquilinum, Asplenium platyneuron, Hieracium gronovii, Oenothera fruticosa, Galium circaezans, Symphyotrichum patens, Symphyotrichum undulatum, Symphyotrichum dumosum, Solidago erecta, Solidago nemoralis, Euphorbia corollata, Parthenium integrifolium, Erigeron strigosus, Hypoxis hirsuta, Galium pilosum, Desmodium laevigatum, Hieracium venosum, Potentilla canadensis, Coreopsis major, Viola palmata, Stylosanthes biflora, Lespedeza virginica, Lespedeza hirta, Lespedeza procumbens, Liatris pilosa, Helianthus divaricatus, Ipomoea pandurata, Chimaphila maculata, Goodyera pubescens, Sericocarpus linifolius, Pycnanthemum tenuifolium, Packera anonyma, Lobelia spicata, Maianthemum racemosum ssp. racemosum, Aristolochia serpentaria, Rudbeckia hirta, Houstonia caerulea, Desmodium paniculatum, Desmodium nudiflorum, Antennaria plantaginifolia, Aureolaria virginica, Fragaria virginiana, Cladonia spp., Euthamia caroliniana, Lespedeza cuneata (I), Lespedeza bicolor (I)

Herb layer - graminoids: Schizachyrium scoparium, Danthonia spicata, Sorghastrum nutans, Piptochaetium avenaceum, Scleria oligantha, Dichanthelium dichotomum, Dichanthelium boscii, Andropogon ternarius, Tripsacum dactyloides, Saccharum alopecuroides, Saccharum brevibarbe var. contortum, Carex albicans, Danthonia sericea, Panicum capillare, Andropogon virginicus, Juncus coriaceus, Sphenopholis obtusata, Panicum philadelphicum, Andropogon gerardii,

(I) = introduced

State and transition model

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T1A	-	Clearcut logging or other large-scale disturbances that cause canopy removal.
T1B	-	Selective removals of the most valuable timber specimens, leaving inferior trees behind.
T1C	-	Mechanical tree/brush/stump/debris removal, seedbed preparation, and planting of perennial grasses and forbs.
T1D	-	Mechanical tree/brush/stump/debris removal, seedbed preparation, applications of fertilizer/lime, and planting of crop or cover crop seed.
T2A	-	Long-term natural succession.
T2B	-	Site preparation and tree planting.
T2C	-	Mechanical tree/brush/stump/debris removal, seedbed preparation, and planting of perennial grasses and forbs.
T2D	-	Mechanical tree/brush/stump/debris removal, seedbed preparation, applications of fertilizer/lime, weed control, planting of crop or cover crop seed.
T3A	-	Clearcut logging or other large-scale disturbances that cause canopy removal.
T3C	-	Mechanical tree/brush/stump/debris removal, seedbed preparation, applications of fertilizer/lime, weed control, and planting of perennial grasses and forbs.
T3D	-	Mechanical tree/brush/stump/debris removal, seedbed preparation, applications of fertilizer/lime, weed control, planting of crop or cover crop seed.
T4A	-	Abandonment of forestry practices.
T4B	-	Timber harvest, mechanical stump and debris removal, seedbed preparation, and planting of perennial grasses and forbs.
T4C	-	Timber harvest, mechanical stump and debris removal, seedbed preparation, fertilizer/lime, weed control, planting of crop or cover crop seed.
T5A	-	Long-term cessation of grazing.
T5B	-	Site preparation and tree planting.
T5C	-	Seedbed preparation, applications of fertilizer/lime, weed control, and planting of crop or cover crop seed.
T6A	-	Agricultural abandonment.
T6B	-	Site preparation and tree planting.
T6C	-	Seedbed preparation, weed control, and planting of perennial grasses and forbs.

State 1 submodel, plant communities

1.1. Triassic Basin Hardpan Woodland - Fire Maintained Phase

1.2. Triassic Basin Hardpan Forest - Fire Suppressed Phase

1.1A	-	Long-term exclusion of fire.
1.2A	-	Prescribed burns and selective removals.

State 2 submodel, plant communities

2.1. Old-field Pine-Hardwood Forest Phase

2.2. Shrub-dominated Successional Phase

2.3. Herbaceous Early Successional Phase

2.1A	-	Clearcut logging.
2.2A	-	Natural succession.
2.2B	-	Brush management.
2.3A	-	Natural succession.

State 6 submodel, plant communities

6.1. Conservation-management Cropland Phase

6.2. Conventional-management Cropland Phase

6.1A	-	Conventional tillage is reintroduced.
6.2A	-	Implementation of conservation tillage and other soil conservation practices

State 1
Reference State

This mature forest state is generally dominated by dry-site oaks or an unusual mixture of dry-site oaks and bottomland oaks. Pines are usually interspersed.

Characteristics and indicators. Stands are uneven-aged with at least some old trees present.

Resilience management. Deer population management is critical to sustaining the diversity of herbaceous understory species.

Community 1.1
Triassic Basin Hardpan Woodland - Fire Maintained Phase

This is an open canopy mature forest community/phase. Regular low-intensity fires have been reintroduced, keeping the understory open, increasing the cover and diversity of herbaceous species and limiting the importance of fire-intolerant woody species.

Resilience management. This community/phase is maintained through regular prescribed burns. The recruitment of fire-adapted oaks and pines benefits from regular low-intensity ground fires, as these forests evolved under a more regular fire regime. Tree ring data suggests that the mean fire return interval of the past in the Southern Piedmont is approximately 6 years, though the actual return interval varied from 3 to 16 years. To approximate the pre-colonial fire regime, prescribed burns should be carried out every 4 to 8 years.

Forest overstory.The overstory is dominated by oaks. Representative species include post oak (Quercus stellata) and blackjack oak (Quercus marilandica). Other important canopy species include shortleaf pine (Pinus echinata), white oak (Quercus alba), willow oak (Quercus phellos), and hickory (Carya glabra, C. tomentosa, C. carolinae-septentrionalis).

Forest understory. Representative understory tree species include blackgum (Nyssa sylvatica), flowering dogwood (Cornus florida), common persimmon (Diospyros virginiana), eastern redcedar (Juniperus virginiana), and eastern redbud (Cercis canadensis). Representative understory shrub species include several species of blueberry (Vaccinium spp.), huckleberry (Gaylussacia spp.), Carolina rose (Rosa carolina), St. Andrew's cross (Hypericum hypericoides ssp. multicaule), and downy arrowwood (Viburnum rafinesqueanum). The herb layer is denser, grassier and more diverse than the fire suppressed phase.

Dominant plant species

post oak (Quercus stellata), tree
blackjack oak (Quercus marilandica), tree
shortleaf pine (Pinus echinata), tree
white oak (Quercus alba), tree
willow oak (Quercus phellos), tree
mockernut hickory (Carya tomentosa), tree
blackgum (Nyssa sylvatica), tree
flowering dogwood (Cornus florida), tree
common persimmon (Diospyros virginiana), tree
eastern redcedar (Juniperus virginiana), tree
deerberry (Vaccinium stamineum), shrub
farkleberry (Vaccinium arboreum), shrub
small black blueberry (Vaccinium tenellum), shrub
Carolina rose (Rosa carolina), shrub
St. Andrew's cross (Hypericum hypericoides ssp. multicaule), shrub
downy arrowwood (Viburnum rafinesqueanum), shrub
New Jersey tea (Ceanothus americanus), shrub
blackberry (Rubus), shrub
blue huckleberry (Gaylussacia frondosa), shrub
trumpet honeysuckle (Lonicera sempervirens), shrub
little bluestem (Schizachyrium scoparium), grass
poverty oatgrass (Danthonia spicata), grass
Indiangrass (Sorghastrum nutans), grass
littlehead nutrush (Scleria oligantha), grass
blackseed speargrass (Piptochaetium avenaceum), grass
cypress panicgrass (Dichanthelium dichotomum), grass
Bosc's panicgrass (Dichanthelium boscii), grass
splitbeard bluestem (Andropogon ternarius), grass
eastern gamagrass (Tripsacum dactyloides), grass
silver plumegrass (Saccharum alopecuroides), grass
western brackenfern (Pteridium aquilinum), other herbaceous
queendevil (Hieracium gronovii), other herbaceous
narrowleaf evening primrose (Oenothera fruticosa), other herbaceous
licorice bedstraw (Galium circaezans), other herbaceous
late purple aster (Symphyotrichum patens), other herbaceous
showy goldenrod (Solidago erecta), other herbaceous
ticktrefoil (Desmodium), other herbaceous
lespedeza (Lespedeza), other herbaceous
flowering spurge (Euphorbia corollata), other herbaceous
wild quinine (Parthenium integrifolium), other herbaceous

Community 1.2
Triassic Basin Hardpan Forest - Fire Suppressed Phase

This is a partially open to closed canopy mature forest community/phase. This phase accounts for the majority of contemporary examples. Canopy cover is higher than in stands in which fire has been reintroduced and the herbaceous understory is typically sparser. The pine component can have a greater proportion of loblolly pine and the understory usually contains a greater proportion of fire-intolerant species.

Forest overstory.The overstory is dominated by oaks. Representative species include post oak (Quercus stellata), blackjack oak (Quercus marilandica), and willow oak (Quercus phellos). Other important canopy species include hickory (Carya glabra, C. tomentosa, C. carolinae-septentrionalis), shortleaf pine (Pinus echinata), loblolly pine (Pinus taeda), and white oak (Quercus alba).

Forest understory. Representative understory tree species include blackgum (Nyssa sylvatica), flowering dogwood (Cornus florida), common persimmon (Diospyros virginiana), eastern redcedar (Juniperus virginiana), eastern redbud (Cercis canadensis), sweetgum (Liquidambar styraciflua), red maple (Acer rubrum), and American holly (Ilex opaca). Representative understory shrub species include several species of blueberry (Vaccinium spp.), huckleberry (Gaylussacia spp.), downy arrowwood (Viburnum rafinesqueanum), and several vines. The herb layer is sparser, less diverse, and less grassy than in the fire maintained phase.

Dominant plant species

post oak (Quercus stellata), tree
blackjack oak (Quercus marilandica), tree
willow oak (Quercus phellos), tree
mockernut hickory (Carya tomentosa), tree
white oak (Quercus alba), tree
shortleaf pine (Pinus echinata), tree
loblolly pine (Pinus taeda), tree
sweetgum (Liquidambar styraciflua), tree
red maple (Acer rubrum), tree
American holly (Ilex opaca), tree
deerberry (Vaccinium stamineum), shrub
farkleberry (Vaccinium arboreum), shrub
small black blueberry (Vaccinium tenellum), shrub
roundleaf greenbrier (Smilax rotundifolia), shrub
muscadine (Vitis rotundifolia), shrub
trumpet creeper (Campsis radicans), shrub
downy arrowwood (Viburnum rafinesqueanum), shrub
blue huckleberry (Gaylussacia frondosa), shrub
poverty oatgrass (Danthonia spicata), grass
whitetinge sedge (Carex albicans), grass
ebony spleenwort (Asplenium platyneuron), other herbaceous
striped prince's pine (Chimaphila maculata), other herbaceous
rattlesnakeweed (Hieracium venosum), other herbaceous

Pathway 1.1A
Community 1.1 to 1.2

Long-term exclusion of fire causes an increase in fire-intolerant understory species and a deterioration of the abundance and diversity of herbaceous species.

Key drivers

Fire
Lack of fire

Key ecosystem services affected

Nutrient cycling
Wildlife habitat
Plant biodiversity

Pathway 1.2A
Community 1.2 to 1.1

The fire suppressed phase can be managed towards the fire maintained phase through a combination of prescribed burns and selective removals. To approximate the pre-colonial fire regime, prescribed burns should be carried out every 4 to 8 years.

Context dependence.After decades of fire suppression, most upland hardwood forests of the Southeast have undergone mesophication, or succession toward forest systems that are less apt to burn. If prescribed fire is to be used as a management tool in fire suppressed ecosystems of the Piedmont, planning will be needed in some forest systems to overcome the effects of mesophication in the early stages of fire reintroduction.

Key drivers

Fire

Key ecosystem services affected

Nutrient cycling
Wildlife habitat
Plant biodiversity

State 2
Secondary Succession State

This state develops in the immediate aftermath of agricultural abandonment, clearcut logging, or other large-scale disturbances that lead to canopy removal. Which species colonize a particular location in the wake of a disturbance does involve a considerable degree of chance. It also depends a great deal on the type, duration, and magnitude of the disturbance event.

Characteristics and indicators. Plant age distribution is even. Plants exhibit pioneering traits such as rapid growth, early reproduction, and shade-intolerance.

Community 2.1
Old-field Pine-Hardwood Forest Phase

This forested successional phase develops in the wake of long-term agricultural abandonment or other large-scale disturbances that have led to canopy removal in the recent past. Stands are even-aged and species diversity is low. The canopy is usually dominated by pines, though opportunistic hardwoods can also be important, particularly in the early stages of tree establishment. Species that exhibit pioneering traits are usually most abundant.

Forest overstory.The overstory is dominated by pines, including loblolly pine (Pinus taeda), Virginia pine (P. virginiana), and shortleaf pine (P. echinata). Generally, Virginia pine becomes increasingly important to the north and west, while loblolly pine is favored toward the south and east.

Forest understory. Sweetgum (Liquidambar styraciflua) is the most representative understory tree species, though its importance tends to decline as the pines mature. Other common species include eastern redcedar (Juniperus virginiana), red maple (Acer rubrum), and sassafras (Sassafras albidum). Seedlings of oaks and hickories are usually present in the understory. These seedlings are released gradually as the forest matures and the pines begin to die off.

Dominant plant species

loblolly pine (Pinus taeda), tree
shortleaf pine (Pinus echinata), tree
sweetgum (Liquidambar styraciflua), tree
eastern redcedar (Juniperus virginiana), tree
Virginia pine (Pinus virginiana), tree
red maple (Acer rubrum), tree
white ash (Fraxinus americana), tree
sassafras (Sassafras albidum), tree
oak (Quercus), tree
hybrid hickory (Carya), tree
greenbrier (Smilax), shrub
trumpet creeper (Campsis radicans), shrub
muscadine (Vitis rotundifolia), shrub
blueberry (Vaccinium), shrub
Japanese honeysuckle (Lonicera japonica), shrub
eastern poison ivy (Toxicodendron radicans), shrub
Virginia creeper (Parthenocissus quinquefolia), shrub
littlehead nutrush (Scleria oligantha), grass
rosette grass (Dichanthelium), grass
ebony spleenwort (Asplenium platyneuron), other herbaceous
wild garlic (Allium vineale), other herbaceous
sparselobe grapefern (Botrychium biternatum), other herbaceous

Community 2.2
Shrub-dominated Successional Phase

This successional phase is dominated by shrubs and vines, along with seedlings of opportunistic hardwoods and pines. It typically develops beginning in the third year after agricultural abandonment or clearcut logging. It grades into the forested successional phase as tree seedlings become saplings and begin to occupy more of the canopy cover.

Forest overstory.Species composition varies considerably from location to location.

Dominant plant species

sweetgum (Liquidambar styraciflua), tree
loblolly pine (Pinus taeda), tree
eastern redcedar (Juniperus virginiana), tree
Callery pear (Pyrus calleryana), tree
winged elm (Ulmus alata), tree
common persimmon (Diospyros virginiana), tree
white ash (Fraxinus americana), tree
black cherry (Prunus serotina), tree
tree of heaven (Ailanthus altissima), tree
blackberry (Rubus), shrub
rose (Rosa), shrub
greenbrier (Smilax), shrub
trumpet creeper (Campsis radicans), shrub
winged sumac (Rhus copallinum), shrub
Japanese honeysuckle (Lonicera japonica), shrub
grape (Vitis), shrub
eastern poison ivy (Toxicodendron radicans), shrub
Chinese privet (Ligustrum sinense), shrub
velvet panicum (Dichanthelium scoparium), grass
broomsedge bluestem (Andropogon virginicus), grass
dogfennel (Eupatorium capillifolium), other herbaceous
Canada goldenrod (Solidago altissima), other herbaceous
aster (Symphyotrichum), other herbaceous
sericea lespedeza (Lespedeza cuneata), other herbaceous
Indianhemp (Apocynum cannabinum), other herbaceous

Community 2.3
Herbaceous Early Successional Phase

This transient community is composed of the first herbaceous invaders in the aftermath of agricultural abandonment, clearcut logging, or other large-scale natural disturbances that lead to canopy removal.

Resilience management. If the user wishes to maintain this community/phase for wildlife or pollinator habitat, a prescribed burn, mowing, or prescribed grazing will be needed at least once annually to prevent community pathway 2.3A. To that end, as part of long-term maintenance, periodic overseeding of wildlife or pollinator seed mixtures can be helpful in ensuring the viability of certain desired species and maintaining the desired composition of species for user goals.

Dominant plant species

greenbrier (Smilax), shrub
Japanese honeysuckle (Lonicera japonica), shrub
trumpet creeper (Campsis radicans), shrub
broomsedge bluestem (Andropogon virginicus), grass
hairy crabgrass (Digitaria sanguinalis), grass
smooth crabgrass (Digitaria ischaemum), grass
southern crabgrass (Digitaria ciliaris), grass
annual bluegrass (Poa annua), grass
annual ragweed (Ambrosia artemisiifolia), other herbaceous
dogfennel (Eupatorium capillifolium), other herbaceous
American burnweed (Erechtites hieraciifolius), other herbaceous
American pokeweed (Phytolacca americana), other herbaceous
Canadian horseweed (Conyza canadensis), other herbaceous
Canada goldenrod (Solidago altissima), other herbaceous
Carolina horsenettle (Solanum carolinense), other herbaceous
aster (Symphyotrichum), other herbaceous
fleabane (Erigeron), other herbaceous
cudweed (Pseudognaphalium), other herbaceous

Pathway 2.1A
Community 2.1 to 2.3

The old-field pine-hardwood forest phase can return to the herbaceous early successional phase through clearcut logging or other large-scale disturbances that cause canopy removal.

Key drivers

Timber management

Pathway 2.2A
Community 2.2 to 2.1

The shrub-dominated successional phase naturally moves towards the old-field pine-hardwood forest through natural succession.

Pathway 2.2B
Community 2.2 to 2.3

The shrub-dominated successional phase can return to the herbaceous early successional phase through brush management, including herbicide application, mechanical removal, prescribed grazing, or fire.

Context dependence.Note: if the user wishes to use this community pathway to create wildlife or pollinator habitat, please contact a local NRCS office for a species list specific to the area of interest and user needs. If the user wishes to maintain the shrub-dominated successional phase long term, for wildlife habitat or other uses, periodic use of this community pathway is necessary to prevent community pathway 2.2A, which happens inevitably unless natural succession is set back through disturbance.

Key drivers

Fire
Livestock grazing or browsing
Brush management initiated by humans.

Pathway 2.3A
Community 2.3 to 2.2

The herbaceous early successional phase naturally moves towards the shrub-dominated successional phase through natural succession. The process takes approximately 3 years on average, barring any major disturbances capable of inhibiting natural succession.

State 3
High-graded Hardwood Forest State

This state develops as a consequence of high-grading, where the most valuable trees are removed, leaving less desirable timber specimens behind. Trees left behind include undesirable timber species, trees of poor form, diseased trees, or genetically inferior trees.

Characteristics and indicators. Typically, high-graded stands consist of a combination of residual stems from the previous stand, a high proportion of undesirable shade-tolerant species, along with some regrowth from desirable timber species. In some cases, large-diameter trees of desirable timber species may be present, but upon closer inspection, these trees usually have serious defects that resulted in their being left behind in earlier cuts.

Resilience management. Landowners with high-graded stands have two options for improving timber production: 1) rehabilitate, or 2) regenerate. To rehabilitate a stand, the landowner must evaluate existing trees to determine if rehabilitation is justified. If the proportion of high-quality specimens present in the stand is low, then the stand should be regenerated. In many cases, poor quality of the existing stand is the result of decades of mismanagement. Drastic measures are often required to get the stand back into good timber production.

Dominant plant species

blackgum (Nyssa sylvatica), tree
common persimmon (Diospyros virginiana), tree
red maple (Acer rubrum), tree
eastern redcedar (Juniperus virginiana), tree
eastern redbud (Cercis canadensis), tree
oak (Quercus), tree
hybrid hickory (Carya), tree
pine (Pinus), tree

State 4
Managed Pine Plantation State

This converted state is dominated by planted timber trees. Loblolly pine (Pinus taeda) is the most commonly planted species. Even-aged management is the most common timber management system.

Note: if the user wishes to convert stands dominated by hardwoods to planted pine, clearcutting will usually be necessary first, allowing herbaceous pioneers to establish on the site in the weeks or months prior to planting. Users should utilize measures described in transition T2B under these circumstances.

Resilience management. Hardwood Encroachment: Hardwood encroachment can be problematic in managed pine plantations. Good site preparation, proper stocking, and periodic thinning are advisable to reduce hardwood competition. Overstocking: The overstocked condition commonly occurs in naturally regenerated stands. When competition from other pines begins to impact the health and productivity of the stand, precommercial thinning should be considered. At this point, the benefit of thinning usually outweighs the potential for invasion and competition from non-pine species. As the target window for thinning passes, the condition of the stand can slowly deteriorate if no action is taken. Under long-term overstocked conditions, trees are more prone to stresses, including pine bark beetle infestation and damage from wind or ice. High-grading: In subsequent commercial thinnings, care should be taken in tree selection. High quality specimens should be left to reach maturity, while slower growing trees or those with defects should be removed sooner. If high quality specimens are harvested first, trees left behind are often structurally unsound, diseased, genetically inferior, or of poor form. This can have long-term implications for tree genetics and for the condition of the stand (Felix III 1983; Miller et al. 1995, 2003; Megalos 2019).

Dominant plant species

loblolly pine (Pinus taeda), tree
sweetgum (Liquidambar styraciflua), tree
red maple (Acer rubrum), tree
sassafras (Sassafras albidum), tree
oak (Quercus), tree
hybrid hickory (Carya), tree
grape (Vitis), shrub
Japanese honeysuckle (Lonicera japonica), shrub
greenbrier (Smilax), shrub
blueberry (Vaccinium), shrub
blackberry (Rubus), shrub
St. Johnswort (Hypericum), shrub
rosette grass (Dichanthelium), grass
littlehead nutrush (Scleria oligantha), grass
broomsedge bluestem (Andropogon virginicus), grass
sedge (Carex), grass
silver plumegrass (Saccharum alopecuroides), grass
sortbeard plumegrass (Saccharum brevibarbe var. contortum), grass
ebony spleenwort (Asplenium platyneuron), other herbaceous
dwarf cinquefoil (Potentilla canadensis), other herbaceous
ticktrefoil (Desmodium), other herbaceous
lespedeza (Lespedeza), other herbaceous

State 5
Pasture/Hayland State

This converted state is dominated by herbaceous forage species.

Resilience management. Overgrazing and High Foot Traffic: In areas that are subject to high foot traffic from livestock and equipment, and/or long-term overgrazing, unpalatable weedy species tend to invade, as most desirable forage species are less competitive under these conditions. High risk areas include locations where livestock congregate for water, shade, or feed, and in travel lanes, gates, and other areas of heavy use. Plant species that are indicative of overgrazing or excessive foot traffic on this ecological site include buttercup (Ranunculus spp.), plantain (Plantago spp.), curly dock (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=RUCR" target="_blank" title="Open in plants.usda.gov">Rumex crispus</a>), sneezeweed (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=HEAM" target="_blank" title="Open in plants.usda.gov">Helenium amarum</a>), cudweed (Pseudognaphalium spp.), slender yellow woodsorrel (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=OXDI2" target="_blank" title="Open in plants.usda.gov">Oxalis dillenii</a>), Carolina horsenettle (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=SOCA3" target="_blank" title="Open in plants.usda.gov">Solanum carolinense</a>), Virginia pepperweed (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=LEVI3" target="_blank" title="Open in plants.usda.gov">Lepidium virginicum</a>), black medick (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=MELU" target="_blank" title="Open in plants.usda.gov">Medicago lupulina</a>), Japanese clover (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=KUST2" target="_blank" title="Open in plants.usda.gov">Kummerowia striata</a>), annual bluegrass (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=POAN" target="_blank" title="Open in plants.usda.gov">Poa annua</a>), poverty rush (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=JUTE" target="_blank" title="Open in plants.usda.gov">Juncus tenuis</a>), rattail fescue (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=VUMY" target="_blank" title="Open in plants.usda.gov">Vulpia myuros</a>), and Indian goosegrass (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=ELIN3" target="_blank" title="Open in plants.usda.gov">Eleusine indica</a>), among others. A handful of desirable forage species are also tolerant of heavy grazing and high foot traffic, including white clover (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=TRRE3" target="_blank" title="Open in plants.usda.gov">Trifolium repens</a>), dallisgrass (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=PADI3" target="_blank" title="Open in plants.usda.gov">Paspalum dilatatum</a>), and bermudagrass (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=CYDA" target="_blank" title="Open in plants.usda.gov">Cynodon dactylon</a>). An overabundance of these species, along with poor plant vigor and areas of bare soil, may imply that excessive foot traffic and/or overgrazing is a concern, either in the present or in the recent past. Soil Fertility and pH Management: Like overgrazing and excessive foot traffic, inadequate soil fertility and pH management can lead to invasion from several common weeds of pastures and hayfields. Species indicative of poor soil fertility and/or suboptimal pH on this ecological site include broomsedge bluestem (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=ANVI2" target="_blank" title="Open in plants.usda.gov">Andropogon virginicus</a>), sweet vernalgrass (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=ANOD" target="_blank" title="Open in plants.usda.gov">Anthoxanthum odoratum</a>), dogfennel (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=EUCA5" target="_blank" title="Open in plants.usda.gov">Eupatorium capillifolium</a>), Japanese clover (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=KUST2" target="_blank" title="Open in plants.usda.gov">Kummerowia striata</a>), common sheep sorrel (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=RUAC3" target="_blank" title="Open in plants.usda.gov">Rumex acetosella</a>), and Carolina horsenettle (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=SOCA3" target="_blank" title="Open in plants.usda.gov">Solanum carolinense</a>), among others. Most of these weedy invaders do not compete well in dense, rapidly growing pastures and hayfields. By maintaining soil fertility and pH, managing grazing to favor desirable forage species, and clipping behind grazing rotations when needed, forage grasses and forbs can usually outcompete weedy invaders. Brush Encroachment: Brush encroachment can be problematic in some pastures, particularly near fence lines where there is often a ready seed source. Pastures subject to low stocking density and long-duration grazing rotations can also be susceptible to encroachment from woody plants. Shorter grazing rotations of higher stocking density can help alleviate pressure from shrubs and vines with low palatability or thorny stems. Clipping behind grazing rotations, annual brush hogging, and multispecies grazing systems (cattle with or followed by goats) can also be helpful. Common woody invaders of pasture on this ecological site include rose (Rosa spp.), blackberry (Rubus spp.), saw greenbrier (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=SMBO2" target="_blank" title="Open in plants.usda.gov">Smilax bona-nox</a>), Japanese honeysuckle (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=LOJA" target="_blank" title="Open in plants.usda.gov">Lonicera japonica</a>), common persimmon (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=DIVI5" target="_blank" title="Open in plants.usda.gov">Diospyros virginiana</a>), sweetgum (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=LIST2" target="_blank" title="Open in plants.usda.gov">Liquidambar styraciflua</a>), eastern redcedar (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=JUVI" target="_blank" title="Open in plants.usda.gov">Juniperus virginiana</a>), and black cherry (<a class="species-link" href="https://plants.usda.gov/core/profile?symbol=PRSE2" target="_blank" title="Open in plants.usda.gov">Prunus serotina</a>).

Dominant plant species

tall fescue (Schedonorus arundinaceus), grass
dallisgrass (Paspalum dilatatum), grass
beaked panicgrass (Panicum anceps), grass
Bermudagrass (Cynodon dactylon), grass
purpletop tridens (Tridens flavus), grass
Indiangrass (Sorghastrum nutans), grass
hairy crabgrass (Digitaria sanguinalis), grass
broomsedge bluestem (Andropogon virginicus), grass
sweet vernalgrass (Anthoxanthum odoratum), grass
white clover (Trifolium repens), other herbaceous
red clover (Trifolium pratense), other herbaceous
vetch (Vicia), other herbaceous
narrowleaf plantain (Plantago lanceolata), other herbaceous
black medick (Medicago lupulina), other herbaceous
field clover (Trifolium campestre), other herbaceous
dogfennel (Eupatorium capillifolium), other herbaceous
common dandelion (Taraxacum officinale), other herbaceous
wild garlic (Allium vineale), other herbaceous

State 6
Cropland State

This converted state produces food or fiber for human uses. It is dominated by domesticated crop species, along with typical weedy invaders of cropland.

Community 6.1
Conservation-management Cropland Phase

This cropland phase is characterized by the practice of no-tillage or strip-tillage, and other soil conservation practices. Though no-till systems offer many benefits, several weedy species tend to be more problematic under this type of management system. In contrast with conventional tillage systems, problematic species in no-till systems include biennial or perennial weeds, owing to the fact that tillage is no longer used in weed management.

Dominant plant species

corn (Zea mays), grass
common wheat (Triticum aestivum), grass
grain sorghum (Sorghum bicolor ssp. bicolor), grass
soybean (Glycine max), other herbaceous

Community 6.2
Conventional-management Cropland Phase

This cropland phase is characterized by the recurrent use of tillage as a management tool. Due to the frequent disturbance regime, weedy invaders tend to be annual herbaceous species that reproduce quickly and are prolific seed producers.

Resilience management. The potential for soil loss is high under this management system. Measures should be put in place to limit erosion.

Dominant plant species

corn (Zea mays), grass
common wheat (Triticum aestivum), grass
grain sorghum (Sorghum bicolor ssp. bicolor), grass
soybean (Glycine max), other herbaceous

Pathway 6.1A
Community 6.1 to 6.2

The conservation-management cropland phase can shift to the conventional-management cropland phase through cessation of conservation tillage practices and the reintroduction of conventional tillage practices.

Context dependence.Soil and vegetation changes associated with this community pathway typically occur several years after reintroduction of conventional tillage practices. These changes continue to manifest as conventional tillage is continued, before reaching a steady state.

Key drivers

Mechanical soil disturbance

Key ecosystem services affected

Erosion control
Climate regulation: carbon cycling and storage
Food and fiber: crops

Pathway 6.2A
Community 6.2 to 6.1

The conventional-management cropland phase can be brought into the conservation-management cropland phase through the implementation of one of several conservation tillage options, including no-tillage or strip-tillage, along with implementation of other soil conservation practices.

Context dependence.Soil and vegetation changes associated with this community pathway typically occur several years after implementation of conservation tillage. These changes continue to manifest as conservation tillage is continued, before reaching a steady state.

Key drivers

Mechanical soil disturbance

Key ecosystem services affected

Erosion control
Climate regulation: carbon cycling and storage
Food and fiber: crops

Transition T1A
State 1 to 2

The reference state can transition to the secondary succession state through clearcut logging or other large-scale disturbances that cause canopy removal.

Key drivers

Timber management

Transition T1B
State 1 to 3

The reference state can transition to the high-graded hardwood forest state through selective removal of the most valuable trees, leaving undesirable timber specimens behind. This may occur through multiple cutting cycles over the course of decades or longer, each cut progressively worsening the condition of the stand.

Key drivers

Timber management

Key ecosystem services affected

Food and fiber: wood products
Plant biodiversity

Transition T1C
State 1 to 5

The reference state can transition to the pasture/hayland state through 1) mechanical tree/brush/stump/debris removal, 2) seedbed preparation, and 3) planting of perennial grasses and forbs.

Context dependence.Herbicide applications, fire, and/or root-raking can be helpful in transitioning treed land to pasture. This is done in part to limit coppicing, as many woody plants are capable of sprouting from residual plant structures left behind after clearing. Judicious use of root-raking is recommended, as this practice can have long-term repercussions with regard to soil structure. Applications of fertilizer and lime can also be helpful in establishing perennial forage species. Grazing should be deferred until grasses and forbs are well established.

Key drivers

Mechanical soil disturbance
Timber management
Seeding

Key ecosystem services affected

Cultural heritage values
Food and fiber: livestock forage
Plant biodiversity
Natural heritage values

Transition T1D
State 1 to 6

The reference state can transition to the cropland state through 1) mechanical tree/brush/stump/debris removal, 2) seedbed preparation, 3) applications of fertilizer/lime, and 4) planting of crop or cover crop seed.

Context dependence.A broad spectrum herbicide, fire, and/or root-raking can be helpful in transitioning treed land to cropland. This is done in part to limit coppicing, as many woody plants are capable of sprouting from residual plant structures left behind after clearing. Judicious use of root-raking is recommended, as this practice can have long-term repercussions with regard to soil structure. Weedy grasses and forbs can also be problematic on these lands.

Key drivers

Mechanical soil disturbance
Timber management
Seeding

Key ecosystem services affected

Cultural heritage values
Erosion control
Climate regulation: carbon cycling and storage
Wildlife habitat
Plant biodiversity
Natural heritage values
Food and fiber: crops

Transition T2A
State 2 to 1

The secondary succession state can transition to the reference state through long-term natural succession. This process can be accelerated to some degree by a combination of prescribed burns and selective harvesting of pines and opportunistic hardwoods.

Transition T2B
State 2 to 4

The secondary succession state can transition to the managed pine plantation state through site preparation and planting of timber trees. Thinning alone may be sufficient for portions of the forest if pines have already established, though it is rarely sufficient for an entire forest patch.

Key drivers

Timber management

Key ecosystem services affected

Food and fiber: wood products

Transition T2C
State 2 to 5

The secondary succession state can transition to the pasture/hayland state through through 1) mechanical tree/brush/stump/debris removal, 2) seedbed preparation, and 3) planting of perennial grasses and forbs.

Context dependence.A broad spectrum herbicide, fire, and/or root-raking can be helpful in transitioning wooded or semi-wooded land to pasture. This is done in part to limit coppicing, as many woody pioneers are capable of sprouting from residual plant structures left behind after clearing. Judicious use of root-raking is recommended, as this practice can have long-term repercussions with regard to soil structure. Applications of fertilizer and lime can also be helpful in establishing perennial forage species. Grazing should be deferred until grasses and forbs are well established.

Key drivers

Livestock grazing or browsing
Seeding
Brush management

Key ecosystem services affected

Food and fiber: livestock forage

Transition T2D
State 2 to 6

The secondary succession state can transition to the cropland state through 1) mechanical tree/brush/stump/debris removal, 2) seedbed preparation, 3) applications of fertilizer/lime, 4) weed control, 5) planting of crop or cover crop seed.

Context dependence.A broad spectrum herbicide, fire, and/or root-raking may be needed to successfully transition land that has been fallow for some time back to cropland. This is done in part to limit coppicing, as many woody pioneers are capable of sprouting from residual plant structures left behind after clearing. Judicious use of root-raking is recommended, as this practice can have long-term repercussions with regard to soil structure. Weedy grasses and forbs can also be problematic on these lands.

Key drivers

Mechanical soil disturbance
Seeding
Mechanical land clearing

Key ecosystem services affected

Erosion control
Climate regulation: carbon cycling and storage

Transition T3A
State 3 to 2

The high-graded hardwood forest state can transition to the secondary succession state through clearcut logging or other large-scale disturbances that cause canopy removal.

Key drivers

Timber management

Transition T3C
State 3 to 5

The high-graded hardwood forest state can transition to the pasture/hayland state through 1) mechanical tree/brush/stump/debris removal, 2) seedbed preparation, and 3) planting of perennial grasses and forbs.

Key drivers

Mechanical soil disturbance
Timber management
Seeding

Key ecosystem services affected

Food and fiber: livestock forage

Transition T3D
State 3 to 6

The high-graded hardwood forest state can transition to the cropland state through 1) mechanical tree/brush/stump/debris removal, 2) seedbed preparation, 3) applications of fertilizer/lime, 4) weed control, 5) planting of crop or cover crop seed.

Context dependence.A broad spectrum herbicide, fire, and/or root-raking can be helpful in transitioning treed land to cropland. This is done in part to limit coppicing, as many woody pioneers are capable of sprouting from residual plant structures left behind after clearing. Judicious use of root-raking is recommended, as this practice can have long-term repercussions with regard to soil structure. Weedy grasses and forbs can also be problematic on these lands.

Key drivers

Mechanical soil disturbance
Timber management
Seeding

Key ecosystem services affected

Erosion control
Climate regulation: carbon cycling and storage
Plant biodiversity
Food and fiber: crops

Transition T4A
State 4 to 2

The managed pine plantation state can transition to the secondary succession state through abandonment of forestry practices (with or without timber tree harvest).

Key drivers

Timber management

Key ecosystem services affected

Food and fiber: wood products

Transition T4B
State 4 to 5

The managed pine plantation state can transition to the pasture/hayland state through 1) timber harvest, 2) mechanical stump and debris removal, 3) seedbed preparation, 4) planting of perennial grasses and forbs.

Context dependence.Applications of fertilizer and lime can be helpful in establishing perennial forage species. Grazing should be deferred until grasses and forbs are well established.

Key drivers

Mechanical soil disturbance
Timber management
Seeding

Key ecosystem services affected

Food and fiber: livestock forage
Food and fiber: wood products

Transition T4C
State 4 to 6

The managed pine plantation state can transition to the cropland state through 1) timber harvest, 2) mechanical stump and debris removal, 3) seedbed preparation, 4) applications of fertilizer/lime, 5) weed control, 6) planting of crop or cover crop seed.

Key drivers

Mechanical soil disturbance
Timber management
Seeding

Key ecosystem services affected

Erosion control
Food and fiber: wood products
Food and fiber: crops

Transition T5A
State 5 to 2

The pasture/hayland state can transition to the secondary succession state through long-term cessation of grazing.

Key ecosystem services affected

Aesthetic values
Food and fiber: livestock forage

Transition T5B
State 5 to 4

The pasture/hayland state can transition to the managed pine plantation state through site preparation and tree planting.

Key drivers

Timber management

Key ecosystem services affected

Food and fiber: livestock forage
Food and fiber: wood products

Transition T5C
State 5 to 6

The pasture/hayland state can transition to the cropland state through 1) seedbed preparation, 2) applications of fertilizer/lime, 3) weed control, and 4) planting of crop or cover crop seed.

Key drivers

Mechanical soil disturbance
Seeding

Key ecosystem services affected

Erosion control
Food and fiber: livestock forage
Climate regulation: carbon cycling and storage
Food and fiber: crops

Transition T6A
State 6 to 2

The cropland state can transition to the secondary succession state through agricultural abandonment.

Transition T6B
State 6 to 4

The cropland state can transition to the managed pine plantation state through site preparation and tree planting.

Key drivers

Timber management
Food and fiber: crops

Key ecosystem services affected

Food and fiber: wood products
Food and fiber: crops

Transition T6C
State 6 to 5

The cropland state can transition to the pasture/hayland state through 1) seedbed preparation, 2) weed control, and 3) planting of perennial forage grasses and forbs.

Context dependence.To convert cropland to pasture or hayland, weed control and good seed-soil contact are important. It is also critical to review the labels of herbicides used for weed control and on the previous crop. Many herbicides have plant-back restrictions, which if not followed could carryover and kill forage seedlings as they germinate. Grazing should be deferred until grasses and forbs are well established.

Key drivers

Mechanical soil disturbance
Seeding

Key ecosystem services affected

Erosion control
Food and fiber: livestock forage
Climate regulation: carbon cycling and storage
Food and fiber: crops

Additional community tables

Table 11. Community 1.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 12. Community 1.2 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 13. Community 2.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 14. Community 2.2 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 15. Community 2.3 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 16. Community 6.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 17. Community 6.2 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Supporting information

Inventory data references

Data collection and analysis of field data will be performed during the Verification Stage of ESD development.

Other references

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Contributors

Yogev Erez
Dee Pederson

Approval

Charles Stemmans, 5/02/2025

Rangeland health reference sheet

Interpreting Indicators of Rangeland Health is a qualitative assessment protocol used to determine ecosystem condition based on benchmark characteristics described in the Reference Sheet. A suite of 17 (or more) indicators are typically considered in an assessment. The ecological site(s) representative of an assessment location must be known prior to applying the protocol and must be verified based on soils and climate. Current plant community cannot be used to identify the ecological site.

Author(s)/participant(s)
Contact for lead author
Date	10/13/2026
Approved by
Approval date
Composition (Indicators 10 and 12) based on	Annual Production

Indicators

Number and extent of rills:
Presence of water flow patterns:
Number and height of erosional pedestals or terracettes:
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
Number of gullies and erosion associated with gullies:
Extent of wind scoured, blowouts and/or depositional areas:
Amount of litter movement (describe size and distance expected to travel):
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
Functional/Structural Groups (list in order of descending dominance by above-ground annual-production or live foliar cover using symbols: >>, >, = to indicate much greater than, greater than, and equal to):

Dominant:

Sub-dominant:

Other:

Additional:
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Average percent litter cover (%) and depth ( in):
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
Potential invasive (including noxious) species (native and non-native). List species which BOTH characterize degraded states and have the potential to become a dominant or co-dominant species on the ecological site if their future establishment and growth is not actively controlled by management interventions. Species that become dominant for only one to several years (e.g., short-term response to drought or wildfire) are not invasive plants. Note that unlike other indicators, we are describing what is NOT expected in the reference state for the ecological site:
Perennial plant reproductive capability:

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Natural ResourcesConservation Service

Ecological site F136XY400NC

Triassic Basin Upland Woodland, Expansive Clay, Seasonally Wet and Dry

Last updated: 5/02/2025 Accessed: 10/13/2026

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General information

MLRA notes

LRU notes

Classification relationships

Ecological site concept

Associated sites

Similar sites

Figure 1. EPA level IV ecoregions of the Southern Piedmont (45).

Figure 2. View of the Southern Piedmont Major Land Resource Area with a focus on Triassic Basins, including the Deep River, Dan River-Danville, Richmond, Davie, Farmville, Scottsville, and Taylorsville basins.

Figure 3. Spatial illustration of soil temperature regimes of the Southern Piedmont.

Figure 4. Spatial extent of this ecological site representing the major areas where this site is important on the landscape.

Table 5. Dominant plant species

Natural Resources
Conservation Service

Last updated: 5/02/2025
Accessed: 10/13/2026