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Ecological site F131AY203AR

St. Francis - Wet Transitional Backswamp Forest

Last updated: 6/10/2025
Accessed: 08/16/2026

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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): 131A–Southern Mississippi River Alluvium

The Southern Mississippi River Alluvium (MLRA 131A) is the largest of 4 MLRAs within Land Resource Region O, the Mississippi Delta Cotton and Feed Grains Region. It occurs in portions of 7 states including Louisiana (32 percent), Arkansas (26 percent), Mississippi (26 percent), Missouri (12 percent), Tennessee (3 percent), Kentucky (1 percent), and Illinois (less than 1 percent). The MLRA is comprised of 29,555 square miles and extends roughly 650 miles from an area near Cape Girardeau, Missouri in the north to the MLRA’s transition to the Gulf Coast Marsh (MLRA 151) in the south. Average elevations range from 330 feet in the north to sea level in the southern part of the area. For much of the north-south distance, the MLRA is bounded to the east by an abrupt rise in elevation of loess-capped bluffs and hills, the Southern Mississippi Valley Loess (MLRA 134). West of the Mississippi River, the boundary is less distinct except to the northwest where the MLRA abuts the Ozark Plateaus and Ouachita province (MLRAs 116A, 117, and 118A). South of the Ozark and Ouachita escarpment, the MLRA adjoins the Southern Mississippi River Terraces (MLRA 131D), which includes the fabled Grand Prairie and merges with the valleys of the Arkansas and Ouachita rivers (MLRA 131B) and the Red River (MLRA 131C). Occurring within or bordering the Southern Mississippi River Alluvium are three separate loess-capped, upland remnants: Crowley’s Ridge, Macon Ridge, and Lafayette Loess Plain, which are western units of MLRA 134 (USDA-NRCS, 2006a).

MLRA 131A is characterized by landscapes that were created and influenced by the current and earlier paths of the Mississippi River and its tributaries. Waters transporting the materials that formed the area originate from as far west as the east slope of the Continental Divide to the western edge of the Appalachian Divide in the east. This comprises a drainage basin of roughly 1,245,000 square miles and includes all or parts of thirty-one U.S. states and two Canadian provinces (Elliott, 1932). The drainage basin of the Mississippi River roughly resembles a funnel, which has its spout at the Gulf of America. Waters from as far east as New York and as far west as Montana contribute to flows in the lower extent of the river (USACE, 2017). The soils of these alluvial landscapes are very deep, dominantly poorly and somewhat poorly drained, and have textures that are mostly loamy or clayey. Principal soil orders are Alfisols, Vertisols, Inceptisols, and Entisols (USDA-NRCS, 2006a).

The fluvial processes that shaped the area were highly dynamic, diverse, and complex. During the Pleistocene epoch, multiple continental glacial-interglacial cycles resulted in extreme fluctuations in river discharge and sediment loads. A braided river regime characterized the fluvial dynamics of the Mississippi River through much of the last glacial cycle (Autin et al., 1991; Rittenhour et al., 2007). Rapid aggradation of glacial outwash led to the development of prominent valley train features over a large portion of the area (Autin et al., 1991; Saucier, 1994; Aslan and Autin, 1999; Blum et al., 2000; Rittenour et al., 2007). A changing climate, meltwater withdrawal, and sea-level change induced a transition from a braided river regime to a predominantly single-channeled, laterally migrating river system during the Holocene epoch (Rittenhour et al., 2007; Shen et al., 2012) – characteristics that continue today. Fluvial dynamics of the migrating river resulted in the development of broad meander belts, backswamp environments, and extensive deltaic complexes (Saucier, 1994; Klimas et al., 2011a).

Tremendous expanses of bottomland hardwood forests once covered much of the area. Today, the land base is largely in agriculture production, and soybeans, cotton, corn, and rice are the principal crops with sugarcane rising in importance in the southernmost portion of the MLRA (USDA-NRCS, 2022).

Due to its size and biophysical variability, the technical team advised subdividing the MLRA into six subregions: Western Lowlands, St. Francis Basin, Yazoo Basin, Tensas Basin, Delta Plain, and Batture.

LRU notes

There are no agency-approved and established Land Resource Units (LRUs) for MLRA 131A. However, the characteristics of each of the six subregions in this MLRA warrant noting and are presented here for each associated ecological site. This provisional ecological site is broadly mapped within the St. Francis Basin.

The St. Francis Basin is geographically positioned in northeastern Arkansas and southeastern Missouri where it, in addition to the Batture and Western Lowlands, form the northern terminus of MLRA 131A. For convenience and ease of administering the Ecological Site Inventory, small portions of the MLRA occurring east of the Mississippi River in extreme western Tennessee and Kentucky are collectively grouped with the basin’s extent in Arkansas and Missouri. The following characterization includes the combined area.

The MLRA boundary of the basin extends some 190 miles (north to south) from Cape Girardeau, Missouri to the vicinity of Helena, Arkansas. For much of its north-south distance, its width (east to west) is approximately 40 miles but narrows considerably south of Memphis, TN. The basin is bounded to the west by Crowley’s Ridge and to the east by the most recent meander belt of the Mississippi River. Elevations range from about 340 feet in the north to around 175 feet in the south (Saucier, 1994). St. Francis Basin includes portions of: Lee, St. Francis, Crittendon, Cross, Poinsett, and Mississippi counties of Arkansas; Pemiscot, Dunkin, New Madrid, and Mississippi counties of Missouri; Lake, Dyer, and Lauderdale counties of Tennessee. Major towns include: West Memphis, Marked Tree, Trumann, Blytheville, Paragould, Piggott, and Black Oak, Arkansas; Caruthersville, Hayti, Portageville, Kennett, Charleston, Sikeston, and Cape Girardeau, Missouri; and Tiptonville, Tennessee. Major highways include: Interstate 55, Interstate 40, U.S. Highway 61, U.S. Highway 63, U.S. Highway 64, U.S. Highway 78, and TN Highway 103.

The geomorphology of the basin is exceedingly complex – manifestations of incredible hydrogeologic and geologic forces. The most significant of these forces for the Mississippi River Valley was serving as a sluiceway through which huge quantities of glacial meltwater and outwash were funneled during multiple continental glaciations. The northwestern two thirds of the basin is mainly comprised of Late Pleistocene (ca. 11,700 to 129,000 years B.P.; chronology after Head, 2019) glacial outwash materials. Large landscapes or “basin subareas” were created or influenced by tremendous amounts of outwash material that, episodically, were released during catastrophic outburst floods of enormous magnitude (Saucier, 1994). Fluvial dynamics of these events resulted in braided river regimes of both the Mississippi and Ohio rivers. Examples of large landscapes that were shaped and reshaped by these fluvial processes and episodes include Sikeston Ridge, Charleston Fan, Morehouse Lowland, and Malden Plain (Stevens and Krusekopf, 2020). Major geomorphic features created in the wake of these forces include prominent sandy ridges; broad, braided-stream terraces (valley trains) at varying elevations or levels; and eolian environments of sand dune fields east of Sikeston Ridge (Saucier, 1994).

A changing climate, meltwater withdrawal, and sea-level change induced a transition from a braided river regime to a predominantly single-channeled, laterally migrating river system during the Holocene epoch (ca. 11,700 years B.P. to present; chronology after Head, 2019) (Rittenour et al., 2007; Shen et al., 2012). Landscapes across the southeastern third of the St. Francis Basin are mainly comprised of former paths of the Mississippi River and its associated alluvial environment of sinuous meander belts. Major landforms comprising the meander belt environment include natural levees, point bar deposits (meander scrolls) and abandoned channels (oxbow lakes) and courses. The higher elevations of natural levees and point bars form an alluvial ridge, which often directs local drainage and floodwaters to the intervening flood basins or backswamps (Saucier, 1994).

In addition to hydrologic influences, the basin’s landscapes are subject to geologic forces. In 1811-1812, four of the largest earthquakes to hit eastern North America occurred in an area that encompassed extreme northeastern Arkansas, southeastern Missouri, and northwestern Tennessee. This area is known as the New Madrid Seismic Zone, which is named after a small settlement near the epicenter of one of the earthquakes (Saucier, 1994). Reports of the New Madrid earthquakes included widespread bank caving, reversal of river flow, landslides, earth waves, forest destruction, land uplifts, and land sinking. A few of the notable land areas or features attributed to or influenced by the seismic events include the St. Francis Sunken Lands, Tiptonville Dome, Ridgely Ridge, Reelfoot Lake, and massive landslides occurring along the adjoining Loess Bluffs of MLRA 134 (Fuller, 1912; Saucier, 1994). Perhaps the most dramatic geomorphic effects were the land fissuring and sand blows resulting from liquefaction (Saucier, 1994). According to Castilla and Audemard (2007), these are “…the largest ever-reported isolated sand blows.” Saucier (1994) emphasized that there are millions of liquefaction features from the earthquakes that are distributed over a 4,000 square mile area.

The movement of water through the basin is influenced by the complex sequence of remnant braided outwash channels, overflow channels, distributaries, and former channels and courses of the Mississippi River. Many of these features convey smaller modern streams within them. Principal streams of the basin are its namesake, the St. Francis River in addition to Little Rivers, Tyronza River, and Pemiscot Bayou (Saucier, 1994). Historically, large floods on the Mississippi River and in the St. Francis tributary system and greater basin led to frequent flooding, inundating landscapes of low relief for very long durations (Moore, 1972). To lessen the severity of flooding, the St. Francis Basin underwent a coordinated and comprehensive flood control and drainage effort. Extensive modification of the basin’s natural hydrology included hundreds of miles of constructed levees along the mainstem of the Mississippi River and basin tributaries; channel modifications on many streams; constructed floodways; water control structures; land leveled areas; and an extensive network of surface drainage systems (Klimas et al., 2013). The extensive modifications to the basin’s hydrology coupled with increased access set the stage for broadscale conversion of former forestland to a variety of land uses with agriculture production being dominant.

All ecological sites in the St. Francis Basin are bounded by the extensive constructed levee system along the Mississippi River. The constructed levee occurs on both sides (i.e., east and west) of the active river channel. The areas protected by levees east of the Mississippi River include portions of Lake, Obion, Dyer, and northern Lauderdale counties in Tennessee and the western extent of Fulton County, Kentucky. (Soils mapped in southern Illinois’s portion of MLRA 131A mostly have a mesic soil temperature regime and do not correlate to this ecological site.) All lands between the river channel and the constructed levee (or Loess Hills where levees are absent) are referred to as the Batture, and that subregion encapsulates its own complement of ecological sites due to significantly different hydrologic regimes (Smith and Klimas, 2002).

Classification relationships

All or portions of the geographic range of this site fall within several ecological and land classifications including:
- NRCS Major Land Resource Area (MLRA) 131A – Southern Mississippi River Alluvium (USDA-NRCS, 2006a)
- National Hierarchical Framework of Ecological Units: 234 Lower Mississippi Riverine Forest Province; 234D White and Black River Alluvial Plains Section; 234Da North Mississippi River Alluvial Plain Subsection (Cleland et al., 2007)
- Environmental Protection Agency Level III Ecoregion: 8.5.2 Mississippi Alluvial Plain; Level IV Ecoregion: Northern Holocene Meander Belt, 73a; Northern Pleistocene Valley Trains, 73b; St. Francis Lowlands, 73c; Northern Backswamp, 73d; Western Lowlands Holocene Meander Belts, 73f; Western Lowlands Pleistocene Valley Trains, 73g (Griffith et al., 1998; Chapman et al., 2002; Woods et al., 2002; Woods et al., 2004; Wiken et al., 2011)
- Mississippi River Low Floodplain (Bottomland), CES203.195 (NatureServe, 2020)
- Sweetgum – Willow Oak (Society of American Foresters, SAF, Type No. 92; Eyre, 1980) and Sugarberry – American Elm – Green Ash (SAF Type No. 93; Eyre, 1980)

Ecological site concept

This site functions as a transitional bridge between the toe and lower backslopes of recent natural levees to the low, clayey backswamp environments. The soils associated with this site are poorly drained to somewhat poorly drained that formed in recent clayey and clayey over loamy alluvium. Reaction of these soils ranges from strongly acid to moderately alkaline but are dominantly nonacid. Permeability through the clayey upper layers is very slow but increases to moderate in the loamy lower horizon(s), where present. Slopes are dominantly 0 to 3 percent but range to 5 percent; the higher slope percentages occur on low, narrow ridges and rises within the flood basin. Flooding typically occurs in winter to early spring with durations that can last from a few days to several weeks depending on flood severity and proximity to flood source. Important canopy trees of this site include sweetgum (Liquidambar styraciflua), Nuttall oak (Quercus texana), water oak (Q. nigra), willow oak (Q. phellos), eastern cottonwood (Populus deltoids), green ash (Fraxinus pennsylvanica), American sycamore (Platanus occidentalis), sugarberry (Celtis laevigata), American elm (Ulmus americana), cedar elm (U. crassifolia), black willow (Salix nigra), red maple (Acer rubrum), and common persimmon (Diospyros virginiana). In northern portions of the site, pin oak (Q. palustris) and hackberry (C. occidentalis) increase in importance. Associates of occasional occurrence include cherrybark oak (Q. pagoda) and pecan (Cara illinoinensis) on drier locations and overcup oak (Q. lyrata) and water hickory (C. aquatica) in areas that remain saturated for longer periods. Dominance patterns are likely to vary tremendously with respect to location, and the prevailing forest type in most areas may be the sugarberry – American elm – green ash association. Former and current land use practices, local drainage patterns, and proximity to other community types, among other factors, contribute to species variability on this site. Most areas, today, are cleared and under various forms of agriculture production.

The species listed in Table 1 were derived from literature reviews, conversations with technical specialists, and limited observations. One or more of the species listed may not be dominant or present at a given location, and opinions may differ as to the dominant or representative species of this ecological site. Extreme caution should be exercised when developing or inferring conservation decisions, actions, or determinations based on Table 1, alone. A more complete listing of species anticipated on this site, including species targeted for their conservation value, can be found in the Ecological Dynamics section of this report.

Associated sites

F131AY201AR	St. Francis - Wet Clayey Backswamp Flat This ecological site occupies the level, wet clayey backswamps, which adjoins F131AY203AR in areas that transition between the recent meander belt to the deep backswamps. Where this occurs, the heavy clay soils of the Sharkey series are typically the representative backswamp soils of site F131AY201AR.
F131AY202AR	St. Francis - Low Clayey Backswamp Ridge Forest This ecological site is characterized by low ridges, rises, and embankments in clayey backswamp environments. It adjoins F131AY203AR locally as that site grades from the margins of the recent meander belt to the wet clayey flood basin.
F131AY214AR	St. Francis - Recent Wet Natural Levee and Meander Scroll Forest This site characterizes the somewhat poorly to poorly drained soils of the toeslope and backslope positions of recent natural levees and occupies one of the lowest positions of the most recent Mississippi River meander belt. The site grades to and adjoins the slightly lower Wet Transitional Backswamp Forest (F131AY203AR).
F131AY105AR	Western Lowlands - Frequently Flooded and Ponded Oxbow and Swale Forest This site is characteristic of prominent depressions including oxbows, meander scroll swales, sloughs, and backswamp depressions. Locally, site F131AY203AR may adjoin the prominent depressions and sloughs of F131AY105AR.

Similar sites

F131AY304MS	Yazoo - Wet Transitional Backswamp Forest This site occupies similar positions and has similar drainage characteristics as F131AY203AR. The principal difference is that F131AY304MS is situated in the Yazoo Basin.
F131AY402LA	Tensas Basin - Poorly Drained Backswamp This ecological site occurs in the Tensas Basin and supports similar concepts as the Wet Transitional Backswamp site (F131AY203AR) of the St. Francis Basin. The principal soils of the latter, Tunica soils, is one of several poorly drained soils that characterizes F131AY402LA.
F131AY502LA	Delta Plain - Poorly Drained Backswamp This ecological site occurs in the Delta Plain and supports similar concepts as the Wet Transitional Backswamp site (F131AY203AR) of the St. Francis Basin. The principal soils of the latter, Tunica soils, is one of several poorly drained soils that characterizes F131AY502LA.
F131AY603MS	Batture - Frequently Flooded Wet Backswamp Flat Forest This ecological site occurs within the Batture and has similar concepts as the Wet Transitional Backswamp site (F131AY203AR) of the St. Francis Basin. The principal soils of the latter, Tunica soils, is one of the characteristic components of F131AY603MS.

Figure 1. Distribution of F131AY203AR.

Table 2. Dominant plant species

Tree	(1) Celtis laevigata (2) Ulmus americana
Shrub	(1) Ilex decidua (2) Campsis radicans
Herbaceous	(1) Laportea canadensis (2) Commelina virginica

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Physiographic features

This ecological site’s distribution in the St. Francis Basin primarily occurs within and along the periphery of Mississippi River meander belts. The site mainly functions as a transitional bridge between the toe and lower backslopes of natural levees and the low backswamp environments of the floodplain. This transitional bridge between the natural levee and the backswamp occurred during the shifting of the Mississippi River channel within the meander belt. Elevation and landscape position of these soils are slightly lower than the Recent Wet Natural Levee and Meander Scroll (F131AY214AR) site but are slightly higher than the adjoining Wet Clayey Backswamp Flat (F131AY201AR) where Sharkey and Alligator soils are dominant. Hence, this site grades from the diverse and complex natural levees and meander scrolls to the wet flood basin or backswamp. Secondarily, the soils of this site have been mapped on swales within meander scrolls.

Figure 1. Block diagram of the recent natural levee-backswamp catena. Keyespoint and Openlake soils correlate to F131AY203AR.

Block diagram illustrating the transition of natural levees to backswamp environments. The Earle series (this site) represents that transition.

Figure 2. Block diagram illustrating the transition of natural levees to backswamp environments. The Earle series (this site) represents that transition.

Table 3. Representative physiographic features

Landforms	(1) Alluvial plain > Backswamp > Rise (2) Meander belt > Meander scroll > Swale
Runoff class	Low to high
Flooding duration	Long (7 to 30 days)
Flooding frequency	None to frequent
Ponding frequency	None
Elevation	150 – 330 ft
Slope	0 – 6 %
Water table depth	5 – 24 in
Aspect	Aspect is not a significant factor

Climatic features

Climate of the St. Francis Basin is classified as Humid Subtropical (Koppen System), which is typified by mostly cool to mild winters; long, hot and humid summers; and no routinely recurring wet or dry season (Klimas et al., 2011b). The average annual air temperature from 1980 through 2010 was 60 degrees F and the mean annual precipitation for the same period was 49 inches.

In the warmer season (and throughout much of the year), winds from the south convey moisture from the Gulf of America leading to humid, semitropical conditions that are favorable for convective thunderstorms. These storms produce a significant proportion of the area’s annual precipitation and are at times accompanied by locally destructive winds. A potential hazard during late summer through early fall is the tropical cyclone. While most impacts from hurricanes and tropical storms are confined along the coastal zone, heavy rainfall, severe flooding, and high winds can occur well into the basin when such systems pass through the area. To the extreme, the region is susceptible to the effects of a strong Bermuda High during the summer, which can cause devastating drought conditions for weeks and even months in some years. Typically, August and September are the driest months of the year with an average monthly low at or less than 2.8 inches.

In the colder season, the area’s weather is dominated by the positions of the Polar and Subtropical Jet Streams, both of which exert strong control over the passages of cold and warm fronts. These fronts alternately bring cold continental air and warm tropical air with periods of varying length. Particularly strong cold fronts can produce large and sudden drops in air temperature; however, cold spells seldom last over a week. The coldest month of the year is typically January with an average monthly low and high of 24 and 47 degrees, respectively. The frost-free period from 1980 to 2010 averaged 181 days basin-wide and ranged from 162 days in the northernmost extent to 193 days in the south. Likewise, the freeze-free period averaged 215 days and ranged from 192 days in the north to 223 days in the southern part of the basin.

Snow and/or sleet falls in the area in most years with the greatest frequency and accumulations occurring in the northern extent. Winter precipitation sometimes occurs as freezing rain and damaging ice storms hit some portion of the basin on occasion. However, these wintry events are generally the exception; they are typically brief and do not persist for very long. Rain is the characteristic form of winter precipitation, and the period of greatest rainfall generally occurs from November through July with April and May being the months of highest averages.

Table 4 Representative climatic features

Frost-free period (characteristic range)	180-190 days
Freeze-free period (characteristic range)	210-220 days
Precipitation total (characteristic range)	50-50 in
Frost-free period (actual range)	170-190 days
Freeze-free period (actual range)	200-220 days
Precipitation total (actual range)	50-50 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 3. Monthly precipitation range

Characteristic range

Actual range

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Figure 4. Monthly minimum temperature range

Characteristic range

Actual range

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Figure 5. Monthly maximum temperature range

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Figure 6. Monthly average minimum and maximum temperature

Figure 7. Annual precipitation pattern

Figure 8 Annual average temperature pattern

Climate stations used

(1) ADVANCE 1 S [USW00093825], Advance, MO
(2) CHARLESTON [USC00231540], Charleston, MO
(3) SIKESTON PWR STN [USC00237772], Sikeston, MO
(4) NEW MADRID [USC00236045], Hickman, MO
(5) MALDEN MUNI AP [USC00235207], Malden, MO
(6) PORTAGEVILLE [USC00236804], Portageville, MO
(7) KENNETT RADIO KBOA [USC00234417], Kennett, MO
(8) CARUTHERSVILLE [USC00231364], Caruthersville, MO
(9) BLYTHEVILLE MUNI AP [USW00053869], Blytheville, AR
(10) PARAGOULD 1S [USC00035563], Paragould, AR
(11) KEISER [USC00033821], Keiser, AR
(12) WEST MEMPHIS MUNI AP [USW00053959], Marion, AR

Influencing water features

This site occurs in a variety of water receiving positions. It’s primary distribution and function is that it forms a bridge between the wet toeslopes of recent natural levees and the low, clayey flats (or talfs) of the flood basin. Secondarily, the soils of this site are mapped locally along or near active tributaries and on some meander scroll swales. The soils are heavily influenced by precipitation, a high water table, and are subject to occasional overland flow and backwater flooding. Today, this site occurs on the protected side of an extensive levee system and no longer receives overland flooding on the same scale that it may have experienced prior to levee construction. Locations that may continue to flood on any predictable basis are typically restricted to stream corridors and other low features (e.g., depressions) that receive overland flow or backwater flooding. Notably, the seasonal high water table and somewhat poorly to poorly drained soils of this site may provide suitable conditions for hydric indicators to be present including both soil and vegetation characteristics. However, in many locations, this site occurs on higher transitional areas and may not meet hydric soil criteria (Kirchner et al., 1992). The soils of this site may prove problematic when attempting wetland determinations, particularly those with thick dark surfaces, such as the Bondurant, Bowdre, Keyespoint, and Tunica series. The dark surfaces of these soils may have organics that mask redoximorphic features, leaving the soils without clear indicators of hydric conditions. Other soils of this site (i.e., Earle, Newellton, and Openlake) are problematic due to the way they were mapped and may show indicators of hydric conditions if examined onsite.

Wetland description

Under the Cowardin et al. (1979) system, this site is classified as:<br />
System: Palustrine<br />
Class: Forested Wetland<br />
Subclass: Broad-leaved Deciduous

Soil features

Please note that the soils listed in this section of the description may not be all inclusive. There may be additional soils that fit the site’s concepts. Additionally, the soils that provisionally form the concepts of this site may occur elsewhere, either within or outside of the MLRA and may or “may not” have the same geomorphic characteristics or support similar vegetation. Some soil map units and soil series included in this “provisional” ecological site were used as a “best fit” for a particular soil-landform catena during a specific era of soil mapping, regardless of the origin of parent material or the location of MLRA boundaries. Therefore, the listed soils may not be typical for MLRA 131A or a specific location, and the associated soil map units may warrant further investigation in a joint ecological site inventory-soil survey project. When utilizing this provisional description, the user is encouraged to verify that the area of interest meets the appropriate ecological site concepts by reviewing the soils, landform, vegetation, and physical location. If the site concepts do not match the attributes of the area of interest, please review the Similar or Associated Sites listed in this description to determine if another site may be a better fit for your area of interest.

This site is characterized by very deep, somewhat poorly and poorly drained soils that formed in recent clayey and clayey over loamy Mississippi River alluvium. Slopes are dominantly 0 to 3 percent but may range upward to 5 and 7 percent on low, narrow ridges or rises. Depending on location, land use history, and soil horizon, reactions generally range from moderately acid to moderately alkaline. The available water capacity is high; organic matter content is moderate; and natural fertility is high. The clayey horizons of these soils have a high shrink-swell potential and permeability is very slow. Permeability improves and generally increases to moderate in the loamy horizons of those soils that have underlying loamy material. These soils are episaturated in the surface layer and along cracks and slickensides in the upper subsoil during the wetter periods of winter into early spring. All underlying layers are wet. Soils provisionally correlated to this site include the Bondurant, Bowdre, Earle, Keyespoint, Newellton, Openlake, Roellen, and Tunica series. Note that these soils may or may not have a hydric rating (depending on location) and can be considered "problematic soils" in that regard due to thick dark surfaces where organics may mask redoximorphic features or where the soils were mapped on lower transitional landscapes.

The Bondurant (fine, smectitic, thermic Fluvaquentic Vertic Endoaquolls) series consists of somewhat poorly drained soils that formed in clayey alluvium in the upper 3.5 to 6 feet and the underlying loamy alluvium. Thickness of the solum is 60 to 80 inches. A key characteristic of these soils is the presence of a mollic epipedon that ranges from 10 to 23 inches thick. Clay content averages 40 to 50 percent in the particle size control section. Cracks around 0.5 to 1.5 inches (1 to 4 cm) wide develop to a depth of 27 to 40 inches (70 to 100 cm) in most years. A lithologic discontinuity is at a depth of 3.5 to 6 feet. The water table is within 1.0 to 2.0 feet during winter and early spring. Slopes range from 0 to 3 percent. Reaction ranges from strongly acid to slightly alkaline throughout.

The Bowdre (clayey over loamy, smectitic, thermic Fluvaquentic Hapludolls) series consists of somewhat poorly drained soils that formed in layered alluvium consisting of a thin clayey layer over loamy and sandy lower layers. Depth to the contrasting loamy layers ranges from 12 to 20 inches from the surface. Permeability is slow in the clayey surface layers but moderate in the underlying loamy material. The water table fluctuates between a depth of 1.5 to 2.0 feet during winter and early in spring. Another distinction of Bowdre soils is the presence of a mollic epipedon that extends to a depth of approximately 16 inches from the surface. Reaction is medium acid to neutral in the A horizon and slightly acid to moderately alkaline in the B and C horizons. Slopes generally range from 0 to 3 percent but may extend to 8 percent, locally. (Depending on the survey area, these soils were mapped either on a transitional zone that bridged the meander belt to backswamp environments (this site) or they were mapped along the base or toe of the natural levee (Site F131AY214AR). The survey areas that mapped Bowdre soils matching the concepts of this site include Cross, Poinsett, and St. Francis counties, Arkansas.)

The Earle (vintage taxonomic classification: clayey over loamy, montmorillonitic, acid, thermic Vertic Haplaquepts) series consists of poorly drained soils that formed in clayey over loamy alluvium. The upper clayey horizons range from 20 to 36 inches thick and exhibit vertic features of slickensides that do not intersect (Bg2 horizon). Earle soils have very slow permeability in the clay horizons, which increases to moderate in the underlying loamy material. These soils have a perched seasonal water table within 12 inches of the soil surface during wet seasons. Reaction ranges from very strongly acid or strongly to slightly acid throughout. Slope gradients are dominantly 0 to 3 percent but range to 6 percent on narrow ridges within the floodplain. (Please note that the vintage taxonomic classification for Earle is based on a classification listed in the Crittenden and Lee County soil survey manuscripts of 1974 and 1977, respectively. A current taxonomic classification is not indicated in the Official Series Description for the Earle series.)

The Keyespoint (clayey over loamy, smectitic over mixed, superactive, nonacid, thermic Vertic Epiaquepts) series consists of somewhat poorly drained soil that formed in recent clayey alluvium in the upper part and loamy alluvium in the lower part. Thickness of the solum ranges from 24 to 38 inches. These soils have vertic properties of slickensides in the upper clayey subsoil, and cracks just under 0.5 to about 1 inch (1 to 2 cm) wide develop to a depth of 20 inches (50 cm) or more in most years. Depth to the contrasting loamy discontinuity is 24 to 40 inches. Reaction ranges from moderately acid to mildly alkaline in the upper layer and subsoil and moderately acid to moderately alkaline in the loamy substratum. Slopes are dominantly 0 to 2 percent but range to 5 percent. Keyespoint soils were formerly mapped in the Tunica series. They differ from Tunica in that they have a chroma of 2 (value of 4 or 5) and up to 3 in the upper part of the Bg horizon, whereas Tunica soils are darker and have a chroma less than 2 or equal to 2 (but with a value of 6) in that horizon.

The Newellton (clayey over loamy, smectitic over mixed, superactive, nonacid, thermic Fluvaquentic Epiaquepts) series consists of somewhat poorly drained soils that formed in recent clayey over older loamy alluvium. Newellton soils have chroma 1 or 2, value 4 or 5 in the clayey upper subsoil. Depth to the contrasting loamy discontinuity is less than 20 inches thick. The clayey upper layers are shallower than either Tunica or Keyespoint soils. The underlying loamy alluvium averages 10 to 28 percent clay content. These soils are wet in the surface layer and wet in the loamy layers below a depth of 1 to 3 feet during December through April in most years. However, the clayey subsoil is not saturated for significant periods of time. Reaction ranges from moderately acid through neutral in the upper layer; moderately acid through slightly alkaline in the Bg horizon; and strongly acid through moderately alkaline in all underlying loamy layers. Slopes are dominantly 0 to 3 percent but may range to 5 percent, locally. Newellton soils were formerly included in the Bowdre series.

The Openlake (fine, smectitic, nonacid, thermic Vertic Epiaquepts) series consists of somewhat poorly drained soils that formed in thick deposits of recent clayey alluvium. Unlike some of the other components of this site, they do not have a clayey over loamy particle-size control section. Openlake soils exhibit vertic properties of slickensides, but average less than 60 percent clay in the particle size control section. The thickness of the solum ranges from 37 to 80 inches. Cracks just under 0.5 to about 1 inch (1 to 2 cm) wide develop to a depth of 20 to 30 inches (50 to 75 cm) in most years. This soil is most often flooded in the winter and early spring and can remain flooded for several days to a month. The water table is within 1 to 2 feet of the surface during the winter and early spring. Reaction ranges from strongly acid to slightly alkaline throughout. Slopes are dominantly 0 to 2 percent but may range to 5 percent in some areas. Openlake soils were formerly included in the Sharkey series. These soils need more study to determine if there are slickensides and wedge-shaped aggregates that meet the requirements for Vertisols classification.

The Roellen (fine, smectitic, thermic Vertic Epiaquolls) series consists of poorly drained, slowly permeable soils that formed in clayey alluvium. A diagnostic characteristic of these soils is the presence of a mollic epipedon that ranges up to 14 inches thick. Cracks extend into the B horizon during dry periods and can remain open for more than 30 cumulative days during the year. A seasonal high water table occurs within 0 to 1 foot of the surface during winter and early spring. The soil commonly is slightly acid or neutral throughout, but it ranges from moderately acid to mildly alkaline. Some pedons are calcareous below a depth of 40 inches. Slopes range from 0 to 2 percent.

The dominant (modal) soils of this site are the Tunica (clayey over loamy, smectitic over mixed, superactive, nonacid, thermic Vertic Epiaquepts) series. This series consists of poorly drained soils that formed in clayey and the underlying loamy alluvium. Tunica soils have vertic properties of slickensides in the upper clayey subsoil. Depth to the contrasting loamy discontinuity ranges from 20 to 36 inches from the surface. Clay content above the discontinuity ranges from 35 to 75 percent and 10 to 32 percent below the discontinuity. They are saturated in the surface layer and along cracks and slickenside faces in the subsoil during December through April in most years. Reaction ranges from moderately acid to slightly alkaline in the clayey upper layers and subsoil and moderately acid to moderately alkaline in the underlying loamy layers. Slopes are dominantly 0 to 3 percent but range to 5 percent on narrow ridges within the flood plain (Soil Survey Staff).

Additional soils may be added to this site as new and updated information suggest their inclusion is warranted. Conversely, some provisional soil components may be transferred to a different site during subsequent phases of ecological site development.

Figure 9. Profile of Newellton soils, Washington County, MS.

Table 5. Representative soil features

Parent material	(1) Alluvium (2) Backswamp deposits
Surface texture	(1) Clay (2) Silty clay (3) Silty clay loam
Family particle size	(1) Clayey over loamy (2) Fine
Drainage class	Poorly drained to somewhat poorly drained
Permeability class	Very slow to moderately rapid
Soil depth	80 in
Surface fragment cover <=3"	Not specified
Surface fragment cover >3"	Not specified
Available water capacity (Depth not specified)	3.4 – 7.8 in
Calcium carbonate equivalent (Depth not specified)	Not specified
Electrical conductivity (Depth not specified)	0 – 1 mmhos/cm
Sodium adsorption ratio (Depth not specified)	Not specified
Soil reaction (1:1 water) (Depth not specified)	5 – 7.3
Subsurface fragment volume <=3" (40in)	0 – 2 %
Subsurface fragment volume >3" (40in)	Not specified

Ecological dynamics

Historically, this ecological site was part of a vast forested landscape with processes and functions directly connected to the highly dynamic nature of the Mississippi River (Gardiner and Oliver, 2005). Today, this site is effectively disconnected from the river via the vast network of constructed levees and, in many areas, local drainage controls. Widespread changes to the landscape occurred long before any intensive studies of the primeval natural communities were conducted. Accordingly, reference conditions of this ecological site are still under review.

The soils of this site are often associated and grouped with other clayey soils of backswamp or “slackwater” environments, such as the Sharkey and Alligator soil series. However, this ecological site is positioned a little higher in elevation, and the loamy subsoils, where present, have better internal drainage than the very deep, heavy clays of either Sharkey or Alligator soils. Although mapped in a variety of floodplain settings, a characteristic occurrence (or distribution) of these clayey over loamy soils is along the lower and wetter periphery of recent natural levees where they typically extend to the lower and much wetter backswamps, often adjoining Sharkey soils (see USDA-SCS, 1958; USDA-SCS, 1961). This ecological site forms a soil and vegetation gradient or transition from the higher riverfront hardwoods of the recent natural levees and point bars to the low, overcup oak – water hickory community of the wet, clayey backswamps (see Ecological Site ID F131AY201AR).

Species occurring on this site consist of a mix of riverfront hardwoods that are tolerant of wet conditions in addition to components that typically occur in low backswamp environments. Tree species listed as frequently occurring on the dominant soils of this site include sweetgum, Nuttall oak, water oak, willow oak, pin oak (northern areas), American elm, sugarberry, hackberry (northern areas), and red maple. Associates or species occasionally occurring include green ash, eastern cottonwood, cherrybark oak, Shumard's oak (Quercus shumardii), pecan, common persimmon, American sycamore, cedar elm, and black willow (Broadfoot and McKnight, 1961; Broadfoot, 1976). The wettest locations may support occasional occurrences of overcup oak and water hickory (Broadfoot and McKnight, 1961).

The species reportedly occurring on these soils overlap with components that are associated with three major forest types, including their variants: sweetgum – willow oak (Society of American Foresters, SAF, type No. 92), American sycamore – pecan – American elm (SAF type No. 94, Mississippi River Valley variant) and sugarberry – American elm – green ash (SAF type No. 93; Eyre, 1980). An important characteristic that has been repeatedly stressed by forest authorities is the transition of the sweetgum – willow oak (often referred to as sweetgum – water oaks or red oaks) and American sycamore – pecan – American elm types to the sugarberry – American elm – green ash association following major disturbances such as heavy cutting or repeated partial harvests (Putnam and Bull, 1932; Putnam, 1951; Hodges, 1997; Oliver et al., 2005). Today, the prevailing association occurring on this ecological site may be the sugarberry – American elm – green ash forest association or a variant of this type given the intensive land use histories most areas have incurred. Eyre (1980) provides a general description of the sugarberry – American elm – green ash type and several components listed above are associates of that type including species that are highly favored in management on this ecological site, such as Nuttall oak, willow oak, water oak, sweetgum, and green ash. Oliver et al. (2005), however, warns that red oaks (e.g., cherrybark, willow, water, and Nuttall) are not regrowing in sufficient concentrations to sustain their former densities, which could impact other factors such as wildlife and commercial timber values. These concerns are founded on forest composition transitioning to a dominantly shade-tolerant community such as the sugarberry – American elm – green ash type. Hodges (1997) emphasized that the latter is long-lived and capable of self-replacement.

Overall, natural cover types on this site are minor compared to other uses. Most areas have been cleared and are used extensively for production, and many areas have been land leveled with soil surface cuts of up to 3 feet to meet irrigation needs. A secondary use on this site is pasturage.

Following this narrative, a “provisional” state and transition model is provided that includes the “perceived” reference state and several alternative (or altered) vegetation states that have been observed and/or projected for this ecological site. This model is based on limited inventories, literature, expert knowledge, and interpretations. Plant communities may differ from one location to the next depending on the severity of local land use activities and rates of deposition. Depending on objectives, the reference plant community may not necessarily be the management goal.

The environmental and biological characteristics of this site are complex and dynamic. As such, the following diagram suggests pathways that the vegetation on this site might take, given that the modal concepts of climate and soils are met within an area of interest. Specific locations with unique soils and disturbance histories may have alternate pathways that are not represented in the model. This information is intended to show the possibilities within a given set of circumstances and represents the initial steps toward developing a defensible description and model. The model and associated information are subject to change as knowledge increases and new information is garnered. This is an iterative process. Most importantly, local and/or state professional guidance should always be sought before pursuing a treatment scenario.

State and transition model

More interactive model formats are also available. View Interactive Models
Click on state and transition labels to scroll to the respective text

T1A	-	Manipulate composition and manage for production (Community 2.1); heavy timber cutting or repeated partial harvests with no management (Community 2.2).
T1B	-	Vegetation/stump removal (mechanical/chemical); preparation for cultivation.
T1C	-	Vegetation/stump removal (mechanical/chemical); seedbed preparation; establishment of desired forage; manage for grazing.
T2A	-	Re-establish missing species; control exotics (mechanical/chemical); timber stand improvement; natural stand dynamics.
T2B	-	Vegetation/stump removal (mechanical/chemical); preparation for cultivation.
T2C	-	Vegetation/stump removal (mechanical/chemical); seedbed preparation; establishment of desired forage; manage for grazing.
T3A	-	Precision land leveling
T3B	-	Vegetation/stump removal (mechanical/chemical); seedbed preparation; establishment of desired forage; manage for grazing.
T3C	-	Natural succession (Community 6.1) or prep area (plow pan breakup, fertilizing, etc.); planting species appropriate for site (Community 6.2).
T3D	-	Establish select native species suitable for site; prep area for planting (herbicide and/or mechanical).
T5A	-	Vegetation/stump removal (mechanical/chemical); preparation for cultivation.
T5B	-	Natural succession (Community 6.1) or prepare area (e.g., plow pan breakup, fertilizing, etc.) for planting tree species appropriate for site (Afforestation - Community 6.2).
T5C	-	Establish select native species suitable for site and prepare area for planting (herbicide and/or mechanical).
T6A	-	Vegetation/stump removal (mechanical/chemical); preparation for cultivation.
T6B	-	Vegetation/stump removal (mechanical/chemical); seedbed preparation; establishment of desired forage; manage for grazing.
T7A	-	Vegetation/stump removal (mechanical/chemical); preparation for cultivation.
T7B	-	Vegetation/stump removal (mechanical/chemical); seedbed preparation; establishment of desired forage; manage for grazing.
T7C	-	Natural succession (Community 6.1) or prepare area (e.g., plow pan breakup, fertilizing, etc.) for planting tree species appropriate for site (Afforestation - Community 6.2).

State 1 submodel, plant communities

1.1. Mixed Bottomland Hardwoods

State 2 submodel, plant communities

2.1. Forest Management

2.2. Non-managed/High-graded

2.1A	-	Cessation of management followed by heavy cutting or repeated partial harvests.
2.2A	-	Silvicultural treatments: removal of undesirable species; re-establish species favored in management; timber stand improvement; establish advance regeneration.

State 3 submodel, plant communities

3.1. Conservation Management

3.2. Transitional Conservation Management

3.3. Conventional Management

3.1A	-	Soil disturbance (tillage); reduction of soil health.
3.1B	-	Conventional tillage, seeding, and fertility management for crops.
3.2A	-	No-till, cover crops, reduced till-soil health improvements.
3.2B	-	Conventional tillage, seeding, and fertility management for crops.
3.3A	-	Reduced till, no-till, and cover crops with soil health improvements as a goal.

State 4 submodel, plant communities

4.1. Land Leveled Cropland

State 5 submodel, plant communities

5.1. Monoculture Grassland

5.2. Mixed Species System

5.3. Mixed Species, Non-seeded

5.4. Early Woody Succession

5.1A	-	Seeding and/or management for desired species composition.
5.1B	-	Species management without overseeding.
5.2A	-	Seeding, fertilizing, management/removal of undesirable species.
5.2B	-	Species management without overseeding.
5.3A	-	Seeding, fertilizing, management/removal of undesirable species.
5.3B	-	Seeding and/or management for desired species composition.
5.3C	-	Lack of disturbance; no (or infrequent) mowing, herbivory, or brush management; natural succession of woody species.
5.4A	-	Brush management/removal of unwanted species.

State 6 submodel, plant communities

6.1. Ruderal/Opportunistic Regrowth

6.2. Afforestation

6.1A	-	Remove undesirable competitors; final soil preparation; establish site-appropriate species (favored in management and suitable for planting).

State 7 submodel, plant communities

7.1. Pollinator Planting/Native Grasses

State 1
Reference: Wet Bottomland Forest

Removal of the historic natural communities of this site occurred long before thorough studies and investigations were conducted. Modifications to the basin's natural hydroperiod and drainage patterns coupled with location-specific land use histories have further complicated species-site relationships. Such complexity will likely be reflected in much variability in vegetation composition and structure of local forest stands (Stanturf et al., 2001). Accordingly, reference conditions for this site have yet to be confirmed, but they are perceived to consist of mature forest stands that support a diverse mix of southern bottomland hardwoods adapted to the somewhat poorly and poorly drained soils of this site. Once assigned or identified, the reference community will not represent the pre-settlement forest community, but it should identify an assemblage of naturally occurring species that reflects and contributes to regional biodiversity and local forest ecology. Implicated in the latter is that the “local” geomorphic features and drainage patterns of this soil-site environment should not have been drastically altered or removed (e.g., land leveled).

The return or transition pathway from the altered states (currently, only State 2) back to reference conditions is intended to represent the suite of hardwood species that, reportedly, frequently to occasionally occur and are favored in management on this site. Realistically, it may not always be possible to return to a “perceived” reference state from a former altered condition. While planting and establishing trees appropriate for a site may be possible, achieving restoration of the understory and other system functions are challenges that may never be realized (Stanturf et al., 2001; Flinn and Vellend, 2005).

Community 1.1
Mixed Bottomland Hardwoods

Components of the reference community are likely to vary by location depending on the local environment. This site mainly occurs as a bridge between the poorly drained periphery of the recent meander belt and the very wet, clayey backswamp environments of the flood basin. Where the site occurs along active tributaries or stream systems, plant composition and structure may be strongly influenced by flooding frequency and duration, deposition or overwash, and pre-existing vegetation along the stream corridor or floodplain. Still, many of the same components are likely to occur in both environments, although dominance patterns may vary.

Species reportedly occurring in older stands of this site include sweetgum, Nuttall oak, water oak, willow oak, American elm, sugarberry, and red maple. Associates or species occasionally occurring include green ash, eastern cottonwood, cherrybark oak, Shumard’s oak (Quercus shumardii), pecan, common persimmon, American sycamore, cedar elm, boxelder (Acer negundo), red mulberry (Morus rubra), and black willow (Broadfoot and McKnight, 1961; Broadfoot, 1976). In northern portions of the site, minor associates may include swamp white oak (Q. bicolor) and shellbark hickory (Carya laciniosa) (Doug Wallace, personal communication). The wettest locations may support occasional occurrences of overcup oak, water hickory, and bald cypress (Taxodium distichum) (Broadfoot and McKnight, 1961). Species characteristic of local floodplains and active tributaries include river birch (Betula nigra), eastern cottonwood, black willow, American sycamore, boxelder, American elm, sugarberry, and green ash. Understory composition may be quite variable depending on the degree of canopy openings or overstory shade but often consist of seedlings and saplings of the preceding in addition to American hornbeam (Carpinus caroliniana), possumhaw (Ilex decidua), blackberry (Rubus spp.), and giant cane (Arundinaria gigantea). A dense woody vine cover is typically present and often represented by poison ivy (Toxicodendron radicans), grape (Vitis spp.), Virginia creeper (Parthenocissus quinquefolia), peppervine (Nekemias arborea), American buckwheat vine (Brunnichia ovata), greenbrier (Smilax spp.), and trumpet creeper (Campsis radicans) (Eyre, 1980; Meadows and Nowacki, 1996). Herbaceous species observed on this site include Canadian woodnettle (Laportea canadensis), Virginia dayflower (Commelina virginica), smallspike false nettle (Boehmeria cylindrica), limestone wild petunia (Ruellia strepens), sedges (Carex spp.), and grasses such as beaked panicgrass (Panicum anceps) and rice cutgrass (Leersia oryzoides) in the wettest locations (Doug Wallace, personal communication).

It’s important to note that a shift in species composition towards a shade tolerant community such as the sugarberry – American elm – green ash type may occur in some stands depending on local land use history. While a precise reference community of this site has not been determined with field validation, interpretations based on data and field studies produced by regional forest authorities suggest that the sweetgum – willow oak forest type, and its variants, are representative (Putnam and Bull, 1932; Putnam, 1951). Several components of the type are highly prized and valued by industry, wildlife and forest specialists, and enthusiasts for the ecological services they provide (Oliver et al, 2005). Broadfoot (1976) provided the following site index ranges (base age 50 years for all species except cottonwood, which is 30 years) and the measured average for select components that are “favored in management” on the dominant soils, the Tunica soil series: Nuttall oak (90-110; average 98 feet), water oak (80-100; average 88 feet), willow oak (80-100; average 90 feet), cherrybark oak (85-105; average 96 feet), sweetgum (85-105; average 86 feet), American sycamore (90-110 feet), eastern cottonwood (90-110 feet), green ash (70-90 feet), and pecan (80-100 feet).

Dominant plant species

sweetgum (Liquidambar styraciflua), tree
Nuttall oak (Quercus texana), tree
water oak (Quercus nigra), tree
willow oak (Quercus phellos), tree
American elm (Ulmus americana), tree
sugarberry (Celtis laevigata), tree
red maple (Acer rubrum), tree
green ash (Fraxinus pennsylvanica), tree
cherrybark oak (Quercus pagoda), tree
American sycamore (Platanus occidentalis), tree
possumhaw (Ilex decidua), shrub
blackberry (Rubus), shrub
eastern poison ivy (Toxicodendron radicans), shrub
peppervine (Nekemias arborea), shrub
American buckwheat vine (Brunnichia ovata), shrub
greenbrier (Smilax), shrub
trumpet creeper (Campsis radicans), shrub
Virginia creeper (Parthenocissus quinquefolia), shrub
grape (Vitis), shrub
sedge (Carex), grass
panicgrass (Panicum), grass
cutgrass (Leersia), grass
Canadian woodnettle (Laportea canadensis), other herbaceous
Virginia dayflower (Commelina virginica), other herbaceous
smallspike false nettle (Boehmeria cylindrica), other herbaceous

State 2
Commercial Forestland

This state consists of two very different community phases and management approaches. Community Phase 2.1 represents forest management and production on this site. A distinguishing feature of this phase is the level of management intensity designed to maximize merchantable goals. Various silvicultural methods are available for selection, and these are generally grouped into even-aged (e.g., clearcutting, seed-tree, and shelterwood) and uneven-aged (e.g., single tree, diameter-limit, basal area, and group selection) approaches (Meadows and Stanturf, 1997). Depending on the method selected, different structural and compositional characteristics of the stand may result. Removal and control of community associates are typically a critical element of production goals. These actions may result in different community or “management phases” (and possibly alternate states) depending on the methods used and desired results. Finding the appropriate approach for a given stand and environment necessitates close consultation with trained, experienced, and knowledgeable forestry professionals. If there is a desire to proceed with this state, it is strongly urged and advised that professional guidance be obtained and a well-designed silvicultural plan developed in advance of any work conducted.

Community Phase 2.2 represents conditions of many stands that have incurred indiscriminate timber harvests (e.g., heavy cutting or diameter-limit harvests of select species) and opportunistic regrowth following such harvests (i.e., no management at any period). Some stands may continue to support a few desirable species and quality stems, but in many instances, affected stands will be comprised of mostly shade tolerant species or trees of desirable species that are defective and fail to meet their maximum potential. (Because of the intensive management required to rehabilitate affected stands, this community phase may warrant elevation to a standalone state. This should be considered in future iterations of this site’s development.)

Although this site is well suited for forest production, seasonal wetness imposes moderate to severe limitations for some forest operations. The principal management concerns are equipment limitations, intense plant competition, and seedling mortality (USDA-SCS, 1990; USDA-NRCS, 2004). Seasonal wetness and periods of heavy precipitation can impose limitations on heavy equipment usage. If possible, equipment operations are best conducted during drier periods of the year, which minimizes soil damage, compaction, erosion, and helps to maintain productivity. A seasonal high water table can kill recently planted seedlings, especially if they are not suited to these wet soils. Conversely, exceedingly long dry periods during the critical “spring flush” in March and April may also lead to seedling mortality, especially on shallow clayey over loamy soils (Mike Oliver, personal communication).

An important caveat of this state is its representation of forest conditions that have retained full site production potential. Currently, transitional pathways to this state originate from another forested state (State 1), only. Former land uses (alternate states) that result in altered conditions of the soil environment (e.g., land leveling) may deleteriously affect predicting and planning for species site selection, tree productivity, and possibly survival of the targeted species. State 6 (Forest Recovery) is representative of forest establishment and growth on locations where soil compaction and reduction of nutrients have occurred due to former land practices. Once a previously affected location has recovered its site potential, transition to this state may be possible. That potential transition is still under review and is currently not shown or addressed in the state and transition model.

Community 2.1
Forest Management

Prescribing a silvicultural system for a given stand depends on species composition and long-term production and postproduction goals (Gardiner et al., 2002). The canopy trees listed in Community Phase 1.1 as “favored in management” are all production options on this site ranging from single species plantations to complex multi-species stands. (Select species favored in management are indicated below under the "Dominant tree species" section for convenience.)

Broadfoot’s (1976) list of species favored in management consists of taxa that are associates of one of the more highly prized forest types of the Southern Mississippi River Alluvium, the sweetgum – willow oak type (Putnam, 1951). Managing for the oaks of this type may be preferred given the multiple values they provide (e.g., timber and wildlife). However, maintaining that component beyond a single rotation (or harvest) may be the most challenging. Creating conditions that promote oak persistence in future stands require a sufficient advance regeneration component. Ensuring that this future crop is established will require close adherence to a well-designed silvicultural plan, which requires programmatic intermediate operations (e.g., improvement cuttings, thinnings, and other partial cuttings). An even-aged silvicultural system that utilizes the clearcutting regeneration method along with brush management to reduce subsequent competition is typically the advocated approach when harvesting bottomland oak stands (Johnson and Shropshire, 1983; Clatterbuck and Meadows, 1993; Hodges, 1995; Meadows and Stanturf, 1997; Oliver et al., 2005). Of caution, some species that are favored in management may not be suitable for planting in every location of this ecological site. Species that are adapted to drier or better drained environments such as cherrybark oak may experience higher seedling mortalities if they are planted in areas that tend to flood or pond for long to very long durations (Mike Oliver, personal communication). Additionally, Broadfoot (1976) cautioned against planting oaks in locations where soil pH is around 7.5. Therefore, each targeted location should be carefully assessed and examined before costs are incurred and seedlings planted.

Except pecan, the remaining trees that are favored in management are light-seeded species. A variety of silvicultural systems may be implemented to promote production of these species including even-aged and group selection (uneven-aged) approaches (see Meadows and Stanturf, 1997). Eastern cottonwood, however, has different challenges due to its extreme shade intolerance and its inability to cast dense shade over the understory. Due to shade intolerance, it cannot succeed itself naturally and requires mechanical site preparation (or scarification) to expose the soil surface prior to establishing and reestablishing following harvests. The relatively “light shading” that its canopy produces permits invasion of shade tolerant species. Many such stands may have dense midstories and understories of American sycamore, pecan, green ash, sugarberry, American elm, boxelder, silver maple, and occasionally sweetgum (Johnson and Shropshire, 1983; Hodges, 1995; Meadows and Stanturf, 1997).

Dominant plant species

sweetgum (Liquidambar styraciflua), tree
Nuttall oak (Quercus texana), tree
water oak (Quercus nigra), tree
willow oak (Quercus phellos), tree
American sycamore (Platanus occidentalis), tree
eastern cottonwood (Populus deltoides), tree
green ash (Fraxinus pennsylvanica), tree
pecan (Carya illinoinensis), tree

Community 2.2
Non-managed/High-graded

This forest community is directly influenced by former harvesting practices that include repeated single-tree selection or diameter-limit harvests with no additional management activities (i.e., brush management, competitor control, etc.). These practices typically target the highest quality trees of the most desirable species. The result is usually an expansion and in-filling of shade tolerant subcanopy trees. Over time, this practice will lead to a predominantly shade tolerant community that may be comprised of American elm, sugarberry, cedar elm, boxelder, red maple, red mulberry, roughleaf dogwood, and possumhaw (Putnam et al., 1960).

Pathway 2.1A
Community 2.1 to 2.2

This pathway includes heavy cutting of the stand that removes the desired species (typically shade intolerant species) of sufficient diameters or repeated single-tree harvests (e.g., diameter-limit cuts) that removes the desired species followed by no management of the residual stand. The resulting stand is typically comprised of shade tolerant species with low commercial value.

Pathway 2.2A
Community 2.2 to 2.1

Intensive management will be required to push a shade tolerant community into a more commercially desirable and viable system. Actions will likely require a complete clearcut of the stand followed by repeated brush and competitor control (chemical and mechanical). If there is a lack of seed source, artificial regeneration will likely be required to reintroduce heavy-seeded species (e.g., oaks). Continual competitor control will be needed.

State 3
Cropland

This state is representative of the dominant land use activity on this ecological site, agriculture production. Crops reportedly grown on the dominant soils of this site include cotton (Gossypium hirsutum), corn (Zea mays), soybeans (Glycine max) and small grains such as wheat (Triticum aestivum) (Snipes et al., 2005). Minor crops, such as some specialty crops (e.g., fruits, vegetables, and tree nuts such as pecans), may be grown locally.

These soils are moderately to well suited to agriculture production depending on local hydrologic regimes, drainage patterns, and the intended crop (USDA-SCS, 1958; USDA-SCS, 1961; USDA-NRCS, 2004). They have moderate to high available water capacity, high natural fertility, and soil reactions that range from mildly acid to moderately alkaline. Applications of fertilizer and lime may not be a necessity everywhere or in every circumstance as these soils are naturally high in phosphorus and potassium and pH levels are generally within a favorable range. Soil tests should be conducted to determine fertilizer, lime, and nitrogen needs on a specific field and for a given crop (USDA-SCS, 1990). Management concerns are largely centered on seasonal high water tables, very slow permeabilities, slow runoff, delayed plantings, soil compaction under equipment traffic, poor tilth, development of a plow pan, and moderate organic matter content (USDA-SCS, 1990; USDA-NRCS, 2004). Areas that are prone to flooding or extended periods of wetness may not be suitable for small grain crops or to crops that require planting in April and May (USDA-SCS, 1990). Management measures to ameliorate some of these issues may include implementing a conservation tillage or management system; subsoiling to breakup plow pans; restricting tillage to appropriate soil moisture content; and establishing a drainage system or network in problematic areas (USDA-NRCS, 2004; USDA-NRCS, 2006b). Of caution, subsurface drainage systems (e.g., pipes or tiles) may not be effective in every situation due to very slow permeability or localized flooding (USDA-SCS, 1990). Major components that producers generally develop and plan are proper selection of crop cultivar, pest control, cropping system, tillage methods, nutrient management, and water management (Snipes et al., 2005). Key practices of some cropping systems often include two or more crops grown in a multiyear rotation, which has been documented to disrupt pest cycles. Leaving crop residue on the surface can help to maintain tilth, fertility, and organic matter content – all critical elements of soil quality and health. For monoculture cropping systems, the implementation of well-designed pest and nutrient management systems are imperative (Pringle et al., 2017). (For assistance, interested parties are advised to visit their local NRCS Field Office.)

Three separate management phases comprise this state: Conservation Management (3.1), Transitional Conservation Management (3.2), and Conventional Management (3.3). The three phases consist of varying tillage methods and approaches to soil health management systems.

Community 3.1
Conservation Management

This cropland phase utilizes long term, continuous conservation management systems that include reduced till and cover crops; no-till with cover crops; crop residue retention; and perennial cropping systems. The guiding principles of this system are minimizing soil disturbance and maximizing soil cover, biodiversity, and the presence of living roots. Implementing diverse crop rotations while maintaining these principles can lend to the development of an integrated pest management plan and contribute to overall system resilience.

Of caution, the above-ground crop growth or yields may not be the best tracking mechanism for assessing the efficacy or presence of this management phase. Indicators of these systems are generally determined via soil-site assessments with outcomes that may include enhanced soil aggregate stability, increased soil biological activity, higher organic matter content, and improved water holding capacity and infiltration rates while also alleviating soil compaction and reducing runoff and erosion (Chessman et al., 2019). Additional advantages to this system that have been noted by some producers are reductions in fuel and labor costs and less wear and tear on machinery and equipment.

There are challenges to this management system, especially in situations where tillage may be considered and/or needed to repair weather damage or other detrimental impacts. Implementation of conventional tillage even after long term conservation practices (e.g., no-till) can reset the affected area back to a conventional cropping system. However, those changes can be reversed and a return to a conservation management system is achievable.

Critical conservation practices associated with this phase include cover crops, no-till, and reduced till as the foundational practices. Additionally, this phase may include supporting and site-specific practices to address conservation needs for a given location.

Community 3.2
Transitional Conservation Management

This cropland phase utilizes a hybrid approach that combines conventional methods with conservation practices at specific periods and under specific situations. Practices under this phase may include a combination of conventional till, reduced till, strip till, and the inclusion of cover crops. For instance, perennial crop species could be in a continuous transitional phase where conventional tillage is implemented at the time of planting followed by reduced tillage during the rotation. Planted forage crops could also be included in this phase, especially when part of a crop rotation that utilizes reduced tillage for one crop followed by conventional tillage for a succeeding crop.

The development, implementation, and refinement of nutrient and pest management plans throughout component operations are imperative. Additionally, this phase may include supporting and site-specific practices to address conservation needs for a given location.

Community 3.3
Conventional Management

This management phase is representative of conventional cropland where tillage is implemented as an annual component of the production system. As crucial elements of the system, conservation practices such as nutrient and pest management are needed to address fertility requirements and pest concerns within the crop cycle. It is important to note that this phase may develop when tillage is implemented to address damage or for other purposes while under a conservation management system (Community Phase 3.1). There could also be associated, supporting, and site-specific practices that are needed to address specific conservation needs. Specific needs may include grade stabilization structures to control gully erosion, grassed waterways to trap sediment from sheet and rill erosion, or implementing reduced till.

Pathway 3.1A
Community 3.1 to 3.2

Soil disturbance (tillage); reduction of soil health.

Pathway 3.1B
Community 3.1 to 3.3

Conventional tillage, seeding, and fertility management for crops.

Pathway 3.2A
Community 3.2 to 3.1

No-till, cover crops, reduced till-soil health improvements.

Pathway 3.2B
Community 3.2 to 3.3

Conventional tillage, seeding, and fertility management for crops.

Pathway 3.3A
Community 3.3 to 3.2

Reduced till, no-till, and cover crops with soil health improvements as a goal.

State 4
Land Formed Cropland

This level to nearly level ecological site oftentimes adjoins gently sloping to undulating landscapes. It is bordered by soils of varying textures and drainage characteristics. Accordingly, inconsistencies in wetness and dryness, ease of operation, and production or yields may occur across a cropped location. An increasingly common practice consists of land forming or leveling surface irregularities into a predetermined and engineered, uniform slope. This practice removes drier and higher features, which are then used to fill wetter and lower positions (e.g., depressions or swales) across the targeted area. Advantages of land leveling may include reduced hazards of erosion and runoff rates, improved surface drainage, and enhanced distribution and conservation of irrigation water. Disadvantages of the practice is a churning of various surface and subsurface materials (former soil horizons) that no longer occur in a predictable or regular pattern. Organic matter content in the surface layer is generally low, and the surface tends to crust and pack after heavy rains (USDA-NRCS, 2006b). One potential hazard that appears to be emerging in some areas is the need for managing surface water runoff. As both irrigated and stormwater runs off leveled fields at uniform rates, surface water tends to collect cumulatively and simultaneously, which places tremendous demands on local drainage systems. Without “in field” structures (natural or artificial) to stagger runoff, the downslope (or lower) ends of some fields tend to back flood thereby contributing to more flooding overall in local watersheds (personal observations).

Immediately following land leveling, the constituent elements of soil health are likely to be absent. In some areas, producers have initiated practices such as applying organic residues (e.g., poultry litter) or growing rice crops for one to two years to rapidly boost fertility and introduce organic matter (via rice biomass) in the surface layer. Over time, the full complement of the management (or community) phases of State 3 may be possible on land leveled fields. They are not repeated or indicated here.

Currently, this state serves as an endpoint in the state and transition model because the ability to predict vegetation response when transitioning to a different state is no longer possible without soil-site investigations for each area of interest. The former soils of this ecological site, including surface and subsurface horizons, will have been redistributed as particles among other former soils depending on the depth of the initial “grade cuts” and leveling efforts.

Community 4.1
Land Leveled Cropland

Some of the crop species and management practices indicated and discussed in State 3 (including all three management phases) may be suitable for establishing on land leveled areas that once supported the soils of this site. However, the type of crops suited for newly leveled areas may ultimately depend on the prevailing soil particle-size distribution and internal drainage characteristics. Former studies on precision leveled fields have noted variabilities and inconsistencies in soil particle-size distributions, bulk density, soil biological properties, and nutrients (Brye et al., 2003; Walker et al., 2003; Brye et al., 2006). Management concerns for this phase may consist of restricted permeability, low organic matter content, and crusting and packing (USDA-NRCS, 2006b). These impacts may be improved by implementing conservation tillage, cover crops, retaining crop residue, and nutrient and pest management strategies.

State 5
Pastureland/Grassland

This state is representative of areas that have been converted to and maintained in pasture or grassland. This group consists of somewhat poorly and poorly drained nonacid clayey soils with a root zone of 20 to 40 inches. Limitations of this state are mainly associated with a seasonally high water table and the flooding of areas that are located along active tributaries. High water tables over long durations will restrict root growth and establishing plants in particularly wet locations may prove challenging. These soils are suited to most commonly grown forage species except bahiagrass (Paspalum notatum), crimson clover (Trifolium incarnatum), and some cool season annual forage plants. Note that bahiagrass and crimson clover do not respond well where soil reactions are above 6.5 (Houck, 2009; Young-Mathews, 2013). Overall, forage production is considered moderate to high when adequately fertilized and properly managed. Lime may not be needed on these nonacid soils.

Given that this ecological site occurs on lower, wetter soils, some forage operations may experience multiple wetness events in a single year. Management concerns are mainly centered on soil compaction due to grazing (USDA-NRCS, 2006b), and overgrazing can lead to numerous bare spots and muddy conditions that effectively reduces or destroys plant establishment and productivity. Planning or prescribing the intensity, frequency, timing, and duration of grazing will be very important on these wetter soils. Of caution, some annual and perennial winter plants naturally growing in wet locations (e.g., sedges, rushes, and some forbs) may be an additional challenge as these are often unpalatable or toxic if consumed.

Flood-prone areas may limit the type of forage suited for this site. In areas that flood on a regular basis, implementing management actions such as planting or overseeding appropriate cool season forage varieties (e.g., ‘Marshall’ ryegrass, Lolium perenne ssp. multiflorum; also known as annual ryegrass) into established warm season grasses at heavy forage rates have been observed to help protect riparian areas from detrimental river or stream scouring (personal observations by Rachel Stout Evans, contributing author). Initiating such remedial actions aid in the recovery and reestablishment of preferred warm season forage following seasonal flooding. (Note that herbicide resistant varieties could be problematic and may warrant reconsideration. Please consult with local NRCS Field Offices for assistance.) Where permissible, a system of artificial drainage or water control structures may be in place to facilitate continued forage production and grazing during wetter periods. Additionally, adjacent higher elevation or protected areas may be needed for the storage of harvested forage or the holding of livestock when wet or flooded conditions occur.

Establishing an effective pasture management program can help minimize degradation of the site and assist in maintaining growth of desired forage. An effective pasture management program includes selecting well-adapted grass and/or legume species that will grow and establish rapidly; maintaining proper soil pH and fertility levels; using controlled grazing practices; mowing at proper timing and stage of maturity; allowing newly seeded areas to become well established before use; and renovating pastures when needed (Rhodes et al., 2005; Green et al., 2006).

This state consists of four community phases that represent a range of forage management options and pasture and hayland condition scenarios. Options range from establishing a forage monoculture for haying to a broad mixture of forage species for production and grazing. It is strongly advised that consultation with local NRCS Service Centers be sought when assistance is needed in developing management recommendations or prescribed grazing practices.

Community 5.1
Monoculture Grassland

This phase is mainly characterized by planting forage species for hay production. Forage plantings generally consist of a single grass species. Native and non-native forage species can be seeded and is usually harvested as hay or haylage, although grazing may occur periodically. These environments are generally productive for forage and can provide ecological benefits to control soil erosion. Allowing for adequate rest and regrowth of desired species is required to maintain productivity. Maintenance of monoculture stands also requires control of unwanted species, which will require pest and nutrient management.

Forage suited for this community phase include hybrid and common Bermudagrass (Cynodon dactylon), dallisgrass (Paspalum dilatatum), or possibly sorghum-Sudangrass hybrid (Sorghum bicolor ssp. drummondii) in drier locations. Tall fescue (Schedonorus arundinaceus) may be an option in the northern portions of the basin. The application of fertilizer is generally needed to establish and maintain improved desirable hayfields and pastures. An additional measure to aid production may include prescribed grazing. Implementing limited and monitored grazing can promote deeper root penetration of grasses with the added benefit of greater nutrient and moisture uptake. This synergistic approach can lead to increased production of and may sustain desirable forages.

Conservation practices should include prescribed grazing or forage harvest management, nutrient and pest management, and potentially other site-specific practices.

Dominant plant species

Bermudagrass (Cynodon dactylon), grass
dallisgrass (Paspalum dilatatum), grass
tall fescue (Schedonorus arundinaceus), grass
Sudangrass (Sorghum bicolor ssp. drummondii), grass

Community 5.2
Mixed Species System

This community is characterized by mixed species composition of grasses and legumes. Components of this forage system are either planted or they established naturally. Typically, perennial warm-season grasses are the foundation of the stand that are periodically overseeded with adapted cool-season forages. The latter creates an added benefit of extending the grazing season. This community phase can be highly productive for grazing and haying operations and can provide beneficial habitat for some wildlife species.

Maintenance of grass stands also requires a series of management practices such as prescribed grazing, brush management, pest management, and nutrient management to maintain production of the desired species. Prescribed grazing includes maintaining proper grazing or forage heights, timing, and stocking rates. Supporting or facilitating practices such as fences, water lines, and watering facilities could be part of the system that maintains this phase.

Dominant plant species

Bermudagrass (Cynodon dactylon), grass
dallisgrass (Paspalum dilatatum), grass
tall fescue (Schedonorus arundinaceus), grass
white clover (Trifolium repens), other herbaceous

Community 5.3
Mixed Species, Non-seeded

This community is characterized by a mixture of native and naturalized non-native species. Forage is usually grazed or harvested as stored forage, hay or haylage. Commonly established species may include Bermudagrass, dallisgrass, and potentially tall fescue in the north.

Stands are generally productive, and forage and grazing management can maintain the community. Healthy stands provide additional benefits by protecting soils from excessive runoff and erosion. However, a common peril associated with this phase is overgrazing, which lowers production and favors less palatable weedy species, especially in areas where livestock congregate. Proper stocking rates or grazing systems that allow for adequate rest and plant regrowth are required to maintain productivity. When forage species are afforded adequate recovery time between grazing intervals, they develop deeper root systems and greater leaf area. Conversely, when plants are not allowed to adequately recover, root development will be restricted leading to lower forage and biomass production. Additionally, maintenance of grass stands requires implementing pest management practices to control unwanted weedy and woody species.

Community 5.4
Early Woody Succession

This community is characterized by a diverse composition of grasses and forbs with an increasing presence of woody species (both native and non-native) that are immature and of low stature. Woody species grow quickly on this site and can be difficult and expensive to control. One potentially problematic species may be honeylocust (Gleditsia triacanthos). Putnam (1951) reported honeylocust as being common on old pastures, and the species can be difficult to remove once established. Management to transition this phase to other forage communities of this state is still possible without excessive inputs and effort, particularly if stem diameters remain below 2 inches and are widely scattered (e.g., a density of less than 100 stems per acre). However, if diameters become greater than 3 inches and densities exceed 300 stems per acre, far more investment, effort, and inputs will be required. If brush management measures are not undertaken, the plant community will transition to the Ruderal/Opportunistic Regrowth (Community Phase 6.1) of State 6.

Of note, this community phase is often very beneficial habitat for some wildlife species, especially a specific guild of resident and Neotropical migratory bird species that are habitat-specific on old field to young tree stand habitats.

Pathway 5.1A
Community 5.1 to 5.2

Seeding and/or management for desired species composition.

Pathway 5.1B
Community 5.1 to 5.3

Species management without overseeding.

Pathway 5.2A
Community 5.2 to 5.1

Seeding, fertilizing, management/removal of undesirable species.

Pathway 5.2B
Community 5.2 to 5.3

Species management without overseeding.

Pathway 5.3A
Community 5.3 to 5.1

Seeding, fertilizing, management/removal of undesirable species.

Pathway 5.3B
Community 5.3 to 5.2

Seeding and/or management for desired species composition.

Pathway 5.3C
Community 5.3 to 5.4

Lack of disturbance; no (or infrequent) mowing, herbivory, or brush management; natural succession of woody species.

Pathway 5.4A
Community 5.4 to 5.3

Brush management/removal of unwanted species.

State 6
Forest Recovery

This state is representative of forest recovery in areas that were once under former intensive land use such as long-term row crop cultivation. Characteristics that distinguish this state from other forest states on this site include a suite of soil-site properties that reportedly affect tree growth such as higher soil bulk density due to compaction, presence of a plow pan, lower organic matter content, and reduced fertility (Baker and Broadfoot, 1979; Groninger et al., 1999). Two community phases are provisionally recognized for this state. Community Phase 6.1 represents natural colonization of tree and shrub species without management. Community Phase 6.2 is representative of intentional forest establishment by artificial regeneration or planting.

For Community Phase 6.2, determining the objectives and goals of the future stand is imperative to increase the probability of successful establishment and production of the afforested area. These decisions will ultimately determine the species to be established, preparation requirements, planting density, and post-planting operations (e.g., competitor control, future improvement cuttings and thinnings, regeneration methods, and overall stand health). Since each area targeted for afforestation may have unique or different land use histories, having a clear understanding of the soil-site conditions is essential. Some areas may necessitate a series of soil improvement actions prior to planting. These actions may include subsoiling or deep plowing to breakup plow pans and fertilizing the targeted area. An additional option is to allow the area to undergo fallowing for a predetermined period (Community Phase 6.1) to potentially increase soil organic matter content, enhance soil aggregate stability, increase soil biological activity, and improve water holding capacity and infiltration rates. Controlling competing vegetation (chemical and mechanical treatment) will most likely be critical. Post-planting operations and maintenance of the stand can enhance survival, future development, and achieve goals and objectives (see Gardiner et al., 2002).

Finding the appropriate approach for a given environment necessitates close consultation with trained, experienced, and knowledgeable forestry professionals. If there is a desire to proceed with this state, it is strongly urged and advised that professional guidance be obtained and a well-designed afforestation and silvicultural plan developed in advance of any work conducted. For an exceptional review and summarization of the afforestation literature, techniques, and practices within the Southern Mississippi River Alluvium, interested parties are directed to Gardiner et al. (2002).

Community 6.1
Ruderal/Opportunistic Regrowth

This community phase is representative of former working lands (e.g., cropland and possibly high concentration areas of former pastureland) that have fallowed and subsequently undergone natural colonization by vegetation. Depending on location, a profusion of growth may initiate within five to ten years of becoming idle – one that typically includes grasses, forbs, woody seedlings and shrubs, and an increasing presence and covering of vines. Initial colonization may be dominant in annuals followed by a shift to perennial vegetation. Shrubs and tree seedlings may appear very early following abandonment, however the rate of colonization and period to stand establishment likely depends on the proximity of established mature stands (Battaglia et al., 1995; Battaglia et al., 2002). If established stands consisting of light-seeded species adjoin fallow fields, colonizing tree species will likely be comprised of those taxa (e.g., elm, sycamore, and cottonwood) (Allen, 1990; Stanturf et al., 2001). Some areas may be far removed from established forest stands. Under this scenario, establishment of woody species (especially overstory tree species) may be very slow, and years may be required before stand establishment is reached (Battaglia et al., 1995; Allen, 1997). In fact, natural colonization by some species may be delayed indefinitely with some stands or areas being understocked (Allen, 1997; Battaglia et al., 2002; Groninger, 2005). Heavy-seeded species like pecan or oaks may not have an opportunity to colonize available areas due to distance and lack of a dependable dispersing agent (e.g., wildlife and water). Non-native invasive species may become part of the developing stand given the proliferation of exotic plant species over the past century.

It is extremely difficult, if not impossible, to predict the future composition and structure of an abandoned field on this site. Many different environmental factors will influence initial colonization and development trajectories. The following projections are simply based on native plant species reported to occur on the soils of this site. As the young stand matures and eventually enters the stem exclusion stage (crown or canopy closure), eastern cottonwood or black willow may be the dominant species if the stand began on bare mineral soils. Otherwise, the developing stand may be largely comprised of associates of the riverfront hardwoods including American sycamore, American elm, sugarberry, green ash, sweetgum, silver maple, boxelder, and eastern cottonwood as a secondary component. Problematic non-native species that may occur include Japanese honeysuckle (Lonicera japonica), Chinese privet (Ligustrum sinense), and possibly Callery pear (Pyrus calleryana). Vines in the young, developing stand may include greenbrier (Smilax spp.), eastern poison ivy, trumpet creeper, grape, Virginia creeper, peppervine, and American buckwheat vine. As the stand matures decades into the future and the overstory stratifies (i.e., the understory reinitiation stage), shade tolerant species may dominate the stand.

Dominant plant species

American sycamore (Platanus occidentalis), tree
American elm (Ulmus americana), tree
green ash (Fraxinus pennsylvanica), tree
sugarberry (Celtis laevigata), tree
boxelder (Acer negundo), tree
silver maple (Acer saccharinum), tree
sweetgum (Liquidambar styraciflua), tree
eastern cottonwood (Populus deltoides), tree
greenbrier (Smilax), shrub
eastern poison ivy (Toxicodendron radicans), shrub
peppervine (Nekemias arborea), shrub
American buckwheat vine (Brunnichia ovata), shrub
trumpet creeper (Campsis radicans), shrub
Virginia creeper (Parthenocissus quinquefolia), shrub

Community 6.2
Afforestation

This community phase is representative of areas planted in tree species that are suited for and favored in management on this ecological site. Preparation of this phase may be initiated immediately following a former landuse activity (e.g., State 3) or it may be started following a fallow period (Community Phase 6.1). If afforestation is initiated immediately following years of conventional tillage without soil-site preparation and improvement efforts, potential productivity of the targeted area could be less than optimal (Baker and Broadfoot, 1979; Groninger et al., 1999; Gardiner et al., 2002).

Groninger et al. (1999) utilized the Baker and Broadfoot (1979) model for site evaluation to predict potential productivity of green ash, Nuttall oak, American sycamore, sweetgum, swamp chestnut oak, water oak, and cottonwood on what they termed “marginal soybean lands.” These are croplands occurring on frequently flooded areas that typically produce low soybean yields under conventional tillage. Soils associated with these areas are generally poorly drained, clayey, and typically classified as hydric. Two of the principal soil series of this site, Newellton and Tunica soils, were included for evaluation. Based on information presented in Groninger et al. (1999), site index predictions on Newellton soils that had undergone extensive conventional tillage ranged 5 to 20 percent lower than what are generally reported in soil survey manuscripts for eastern cottonwood, green ash, Nuttall oak, sweetgum, and water oak. The estimated site index values for those species were listed as 80, 77, 61, 81, and 72 for cottonwood, green ash, Nuttall oak, sweetgum, and water oak, respectively. The same site index predictions on Tunica soils indicated a 17 to 19 percent reduction for eastern cottonwood and sweetgum, respectively. Estimated site index values on Tunica soils were 75 for eastern cottonwood and 73 for green ash. Comparing the Baker and Broadfoot (1979) estimated site index values of former conventional tilled cropland to the site index values generated from long established forestland are noteworthy (see Community Phase 1.1 for Tunica soils). The site index predictions in Groninger et al. assumes that no soil-site improvement actions were undertaken. (Note that site index is the height in feet of select tree species at 50 years of growth except for eastern cottonwood which is height in 30 years of growth.)

Over the years, various afforestation innovations have increased the likelihood of success in addition to soil-site amelioration such as planting large, high-quality seedlings with well-developed root systems in an appropriate cover crop (Dey et al., 2010); interplanting seedlings within a fast-growing pioneer species nurse crop (e.g., cottonwood) (Gardiner et al., 2001); and planting companionable species combinations for mixed species stands (Lockhart et al., 2008). The cover crop and nurse crop approaches reportedly help to control rapid overtopping and crowding by competing vegetation and wildlife herbivory (Dey et al., 2010). A completely different approach must be taken if eastern cottonwood is the sole targeted species for planting. For eastern cottonwood, all potential competitors must be removed and the soil surface scarified via mechanical site preparation (Johnson and Shropshire, 1983; Hodges, 1995; Meadows and Stanturf, 1997). Finding the appropriate strategy for a given location requires matching the species to the local hydrologic and soil-site environment; determining short- and long-term objectives and goals; and implementing the appropriate management actions at the required intervals.

Several species that frequently occur and are favored in management are likely appropriate for planting on this ecological site. Broadfoot (1976) listed sweetgum, Nuttall oak, green ash, eastern cottonwood, and American sycamore as species suitable for planting. He also listed cherrybark oak, water oak, and willow oak as species to favor in management. The desirability and importance for establishing oaks have prompted many to attempt plantings on sites that were not conducive to oak production. Some of these former attempts likely targeted high pH soils (i.e., nonacid or alkaline) or species selections that were site incompatible (Mike Oliver, personal communication). Broadfoot warned against planting oaks on locations where soil reactions are pH 7.5 or higher. If oaks are planted on this site, intensive plant competition will likely dictate the need for scheduled competitor control efforts that cannot be delayed or postponed. If cherrybark oak is chosen to be planted, then targeted locations should be better drained than low-lying areas that remain wet for long periods, and even then, productivity may be lower than anticipated.

Dominant plant species

sweetgum (Liquidambar styraciflua), tree
Nuttall oak (Quercus texana), tree
green ash (Fraxinus pennsylvanica), tree
eastern cottonwood (Populus deltoides), tree
American sycamore (Platanus occidentalis), tree

Pathway 6.1A
Community 6.1 to 6.2

Remove undesirable competitors; final soil preparation; establish site-appropriate species (favored in management and suitable for planting).

State 7
Conservation (Herbaceous)

This state is representative of the range of conservation actions that may be implemented and established on this ecological site. Apart from planting trees and managing for forest, one may elect to establish native herbaceous species and manage for predominantly a native grassland; a complex mixture of native grasses and forbs; or a pollinator planting whereby native forbs dominate the mix. In each of these options, it is strongly advised (possibly a programmatic requirement) that the species comprising the planting or seed mix consist of spring, summer, and fall flowering species. Depending on goals and objectives, various conservation programs and practices may be available. For additional information and assistance, please contact or visit the local NRCS Field Office.

Community 7.1
Pollinator Planting/Native Grasses

This community phase represents the establishment of native forbs or wildflowers for pollinator habitat or native grasses. The seed mix for planting may be quite varied depending on objectives and goals. Ideally, the mix includes a wide range of species that flower at various times of the growing season (spring, summer, and fall). Plant species in some pollinator mixes may include but are not limited to beebalm (Monarda spp.), milkweeds (Asclepias spp.), beardtongue (Penstemon spp.), vervain (Verbena spp.), various legumes such as native lespedeza (Lespedeza spp.), Illinois bundleflower (Desmanthus illinoensis), partridge pea (Chamaecrista fasciculata), and a broad assortment of composites such as asters (Symphyotrichum spp.), tickseed (Coreopsis spp.), blazing star (Liatris spp.), coneflower (Rudbeckia spp.), sunflower (Helianthus spp.) among many others. If goals and objectives are to establish native grasses within a forb mix or in a grass-dominant stand, species suitable for planting may include switchgrass (Panicum virgatum), eastern gamagrass (Tripsacum dactyloides), big bluestem (Andropogon gerardii), little bluestem (Schizachyrium scoparium) and Indiangrass (Sorghastrum nutans). Of caution, if eastern gamagrass is chosen to be planted, soil pH must be below 8.0 as the species’ productivity falters under alkaline conditions (Henson, 2012).

Key to the establishment of this phase is initial preparation, seeding rate, planting period, follow-up treatment, and maintenance of the planting. The selection of species to establish on any given area may ultimately depend on size and conditions of the location where the planting will occur, landowner/manager goals and objectives, and the advice and knowledge of the conservation practitioner.

Transition T1A
State 1 to 2

Stand composition is heavily altered and managed to favor select species for production (Community Phase 2.1). This transitional pathway also includes heavy timber cutting and/or repeated partial harvests (high-grading) leading to Community Phase 2.2.

Transition T1B
State 1 to 3

Actions include mechanical removal of vegetation and stumps; herbicide treatment of residual plants; and preparation for cultivation.

Transition T1C
State 1 to 5

Actions include mechanical removal of vegetation and stumps; herbicide treatment of residual plants; seedbed preparation; and establishment of desired forage.

Transition T2A
State 2 to 1

This transition represents a return to perceived reference conditions and involves the reestablishment of missing species; the control or removal of exotic species (herbicide and mechanical); stand improvement practices that favors a return of more shade intolerant components.

Transition T2B
State 2 to 3

Actions include mechanical removal of vegetation and stumps; herbicide treatment of residual plants; and preparation for cultivation.

Transition T2C
State 2 to 5

Actions include mechanical removal of vegetation and stumps; herbicide treatment of residual plants; seedbed preparation; and establishment of desired forage.

Transition T3A
State 3 to 4

Precision land leveling

Transition T3B
State 3 to 5

Vegetation/stump removal (mechanical/chemical); seedbed preparation; establishment of desired forage; manage for grazing.

Transition T3C
State 3 to 6

Natural succession (Community 6.1) or prep area (plow pan breakup, fertilizing, etc.); planting species appropriate for site (Community 6.2).

Transition T3D
State 3 to 7

Establish select native species suitable for site; prep area for planting (herbicide and/or mechanical).

Transition T5A
State 5 to 3

Actions include mechanical removal of vegetation; herbicide treatment of residual plants; and preparation for cultivation.

Transition T5B
State 5 to 6

Natural succession (Community 6.1) or prepare area (e.g., plow pan breakup, fertilizing, etc.) for planting tree species appropriate for site (Afforestation - Community 6.2).

Transition T5C
State 5 to 7

Establish select native species suitable for site and prepare area for planting (herbicide and/or mechanical).

Transition T6A
State 6 to 3

Cropland establishment: vegetation removal (mechanical/chemical) and preparation for cultivation.

Transition T6B
State 6 to 5

Mechanical removal of vegetation and stumps; herbicide treatment of residual plants; establish desired forage species and manage for grazing.

Transition T7A
State 7 to 3

Cropland establishment: vegetation removal (mechanical/chemical) and preparation for cultivation.

Transition T7B
State 7 to 5

Establish desired forage species and manage for grazing.

Transition T7C
State 7 to 6

Natural succession (Community 6.1) or prepare area (e.g., plow pan breakup, fertilizing, etc.) for planting tree species appropriate for site (Afforestation - Community 6.2).

Additional community tables

Table 6. Community 1.1 plant community composition

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

Table 7. Community 2.1 plant community composition

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

Table 8. Community 2.2 plant community composition

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

Table 9. Community 3.1 plant community composition

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

Table 10. Community 3.2 plant community composition

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

Table 11. Community 3.3 plant community composition

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

Table 12. Community 4.1 plant community composition

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

Table 13. Community 5.1 plant community composition

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

Table 14. Community 5.2 plant community composition

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

Table 15. Community 5.3 plant community composition

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

Table 16. Community 5.4 plant community composition

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

Table 17. Community 6.1 plant community composition

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

Table 18. Community 6.2 plant community composition

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

Table 19. Community 7.1 plant community composition

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

Supporting information

Inventory data references

The information provided on the states and community phases in this provisional description report were generated from literature reviews, conversations with technical specialists, and limited personal observations and experience on this soil-site environment. Intensive vegetation inventories were not conducted during the development of this provisional report. Those tasks will occur during future phases of ecological site development.

Other references

Allen, J.A. 1990. Establishment of bottomland oak plantations on the Yazoo National Wildlife Refuge Complex. Southern Journal of Applied Forestry 14(4): 206-210.

Allen, J.A. 1997. Reforestation of bottomland hardwoods and the issue of woody species diversity. Restoration Ecology 5(2): 125-134.

Aslan, A. and W.J. Autin. 1999. Evolution of the Holocene Mississippi River floodplain, Ferriday, Louisiana: Insights on the origin of fine-grained floodplains. Journal of Sedimentary Research 69: 800-815.

Autin, W.J., S.F. Burns, B.J. Miller, R.T. Saucier, and J.I. Snead. 1991. Quaternary geology of the Lower Mississippi Valley. p. 547-582. In R.B. Morrison (Editor). Quaternary Nonglacial Geology: Conterminous U.S. Geological Society of America. The Geology of North America, Volume K-2. Boulder, CO.

Baker, J.B. and W.M. Broadfoot. 1979. A practical field method of site evaluation for commercially important southern hardwoods. General Technical Report SO-26. Southern Forest Experiment Station, New Orleans, LA. 51p.

Battaglia, L.L., J.R. Keough, and D.W. Pritchett. 1995. Early secondary succession in a southeastern U.S. alluvial floodplain. Journal of Vegetation Science 6(6): 769-776.

Battaglia, L.L., P.R. Minchin, and D.W. Pritchett. 2002. Sixteen years of old-field succession and reestablishment of a bottomland hardwood forest in the Lower Mississippi Alluvial Valley. Wetlands 22(1): 1-17.

Blum, M.D., M.J. Guccione, D.A. Wysocki, P.C. Robnett, and M. Rutledge. 2000. Late Pleistocene evolution of the Lower Mississippi Valley, southern Missouri to Arkansas. Geological Society of America Bulletin 112: 221-235.

Broadfoot, W.M. 1976. Hardwood suitability for and properties of important Midsouth soils. USDA Forest Service Research Paper SO-127. Southern Forest Experiment Station, New Orleans, LA. 84 p.

Broadfoot, W.M. and J.S. McKnight. 1961. Soil suitability for hardwoods in the Mississippi Delta. Information Sheet 716. Agriculture Experiment Station, Mississippi State University, State College, Mississippi. Delta Branch Experiment Station, Stoneville, MS. 2 p.

Brye, K.R., N.A. Slaton, M.C. Savin, R.J. Norman, and D.M. Miller. 2003. Short-term effects of land leveling on soil physical properties and microbial biomass. Soil Science Society of America Journal 67: 1405-1417.

Brye, K.R., N.A. Slaton, and R.J. Norman. 2006. Soil physical and biological properties as affected by land leveling in a clayey Aquert. Soil Science Society of America Journal 70: 631-642.

Castilla, R.A. and F.A. Audemard. 2007. Sand blows as a potential tool for magnitude estimation of pre-instrumental earthquakes. Journal of Seismology 11(4): 473-487.

Chapman, S.S., J.M. Omernik, G.E. Griffith, W.A. Schroeder, T.A. Nigh, and T.F. Wilton. 2002. Ecoregions of Iowa and Missouri (color poster with map, descriptive text, summary tables, and photographs): Reston, Virginia, U.S. Geological Survey (map scale 1:1,800,000).

Chessman, D., B.N. Moebius-Clune, B.R. Smith, and B. Fisher. 2019. The basics of addressing resource concerns with conservation practices within integrated soil health management systems on cropland. Soil Health Technical Note No. 450-04. U.S. Department of Agriculture, Natural Resources Conservation Service. Available: https://directives.sc.egov.usda.gov/OpenNonWebContent.aspx?content=44340.wba (Accessed: 9 September 2020).

Clatterbuck, W.K. and J.S. Meadows. 1993. Regenerating oaks in the bottomlands. p: 184-195. In: D.L. Loftis and C.E. McGee (Editors). Oak Regeneration: Serious Problems, Practical Recommendations. Symposium Proceedings, 8-10 September 1992, Knoxville, TN. General Technical Report SE-84. USDA Forest Service, Southeastern Forest Experiment Station, Asheville, NC.

Cleland, D.T., J.A. Freeouf, J.E. Keys, G.J. Nowacki, C.A. Carpenter, and W.H. McNab. 2007. Ecological Subregions: Sections and Subsections for the conterminous United States. General Technical Report WO-76D, Map on CD-ROM (A.M. Sloan, cartographer). U.S. Department of Agriculture, Forest Service, Washington, DC. presentation scale 1:3,500,000; colored.

Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deepwater habitats of the United States. U.S. Department of the Interior, Fish and Wildlife Service, Washington, D.C. FWS/OBS 79/31. 103 p.

Dey, D.C., E.S. Gardiner, J.M. Kabrick, J.A. Stanturf, and D.F. Jacobs. 2010. Innovations in afforestation of agricultural bottomlands to restore native forests in the eastern USA. Scandinavian Journal of Forest Research 25(S8): 31-42.

Elliott, D.O. 1932. The Improvement of the Lower Mississippi River for Flood Control and Navigation. Volume 1. U.S. Waterways Experiment Station, Vicksburg, MS.

Eyre, F.H. 1980. Forest cover types of the United States and Canada. Society of American Foresters, Washington, DC. 148 p.

Flinn, K.M. and M. Vellend. 2005. Recovery of forest plant communities in post-agricultural landscapes. Frontiers in Ecology and the Environment 3(5): 243-250.

Fuller, M.L. 1912. The New Madrid Earthquake. U.S. Geological Survey Bulletin 494. 120 p.

Gardiner, E.S. and J.M. Oliver. 2005. Restoration of bottomland hardwood forests in Lower Mississippi Alluvial Valley, U.S.A. p. 235-251. In: J.A. Stanturf and P. Madsen (Editors). Restoration of Boreal and Temperate Forests. Boca Raton, FL: CRC Press.

Gardiner, E.S., D.R. Russell, M. Oliver, and L.C. Dorris, Jr. 2002. Bottomland hardwood afforestation: state of the art. p. 75-86. In: M.M. Holland, M.L. Warren, and J.A. Stanturf (Editors). Proceedings of a conference on sustainability of wetlands and water resources: how well can riverine wetlands continue to support society into the 21st century? General Technical Report SRS-50. USDA Forest Service, Southern Research Station, Asheville, NC.

Gardiner, E.S., C.J. Schweitzer, and J.A. Stanturf. 2001. Photosynthesis of Nuttall oak (Quercus nuttallii Palm.) seedlings interplanted beneath an eastern cottonwood (Populus deltoides Bartr. ex Marsh.) nurse crop. Forest Ecology and Management 149: 283-294.

Green, Jonathan D., W.W. Witt, and J.R. Martin. 2006. Weed management in grass pastures, hayfields, and other farmstead sites. University of Kentucky Cooperative Extension Service, Publication AGR-172.

Griffith, G.E., J.M. Omernik, S. Azevedo. 1998. Ecoregions of Tennessee (color poster with map, descriptive text, summary tables, and photographs): Reston, VA., U.S. Geological Survey (map scale 1:1,000,000).

Groninger, J.W. 2005. Increasing the impact of bottomland hardwood afforestation. Journal of Forestry 103(4): 184-188.

Groninger, J.W., M.W. Aust, M. Miwa, and J.A. Stanturf. 1999. Tree species-soil relationships on marginal soybean lands in the Mississippi Delta. p. 205-209. In: J.D. Haywood (Editor). Proceedings of the Tenth Biennial Southern Silvicultural Research Conference, Shreveport, LA. General Technical Report SRS-30. USDA Forest Service, Southern Research Station, Asheville, NC. 632 p.

Head, M.J. 2019. Formal subdivision of the Quaternary System/Period: Present status and future directions. Quaternary International 500: 32-51.

Henson, J.F. 2012. Plant Guide for eastern gamagrass (Tripsacum dactyloides). USDA-Natural Resources Conservation Service, National Plant Data Center, Baton Rouge, LA 70803.

Hodges, J.D. 1995. The southern bottomland hardwood region and brown loam bluffs subregion. p. 227-269. In: J.W. Barrett (Editor). Regional Silviculture of the United States. Third Edition. John Wiley & Sons, Inc., New York, NY.

Hodges, J.D. 1997. Development and ecology of bottomland hardwood sites. Forest Ecology and Management 90: 117-125.

Houck, M., 2009. Plant fact sheet for bahiagrass (Paspalum notatum Flüggé). USDA-Natural Resources Conservation Service, Louisiana State Office, Alexandria, Louisiana 71302.

Johnson, R.L. and F.W. Shropshire. 1983. Bottomland Hardwoods. p. 175-179. In: R.M. Burns (Editor). Silvicultural Systems for the Major Forest Types of the United States. Agricultural Handbook 445. USDA Forest Service, Washington, DC.

Kirchner, W.N., B.A. Kleiss, E.J. Clairain, Jr., W.B. Parker, and C.J. Newling. 1992. Delineation of Wetlands of the Yazoo River Basin in Northwestern Mississippi. Miscellaneous Paper EL-92-2, U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS.

Klimas, C.V., E.O. Murray, J. Pagan, H. Langston, and T. Foti. 2011b. A Regional Guidebook for Applying the Hydrogeomorphic Approach to Assessing Functions of Forested Wetlands in the Delta Region of Arkansas, Lower Mississippi River Alluvial Valley, Version 2.0. U.S. Army Corps of Engineers, Ecosystem Management and Restoration Research Program, ERDC/EL TR-11-12.

Klimas, C., J. Pagan, T. Foti., and B.E. Tirpak. 2011a. Potential Natural Vegetation of the Mississippi Alluvial Valley: Yazoo Basin, Mississippi. U.S. Fish and Wildlife Service, Lower Mississippi Valley Joint Venture. Vicksburg, MS.

Klimas, C., T. Foti, J. Pagan, and M. Williamson. 2013. Potential Natural Vegetation of the Mississippi Alluvial Valley: St. Francis Basin, Arkansas, Field Atlas. U.S. Army Corps of Engineers, Ecosystem Management and Restoration Research Program, ERDC/EL TR-12-23.

Lockhart, B.R., E. Gardiner, T. Leininger, and J. Stanturf. 2008. A stand-development approach to oak afforestation in the Lower Mississippi Alluvial Valley. Southern Journal of Applied Forestry 32(3): 120-129.

Meadows, J.S. and G.J. Nowacki. 1996. An old-growth definition for eastern riverfront forests. General Technical Report SRS-4. U.S. Department of Agriculture, Forest Service, Southern Research Station, Asheville, NC. 7 p.

Meadows, J.S. and J.A. Stanturf. 1997. Silvicultural systems for southern bottomland hardwoods. Forest Ecology and Management 90: 127-140.

Moore, N.R. 1972. Improvement of the Lower Mississippi River and Tributaries 1931-1972. Mississippi River Commission, Vicksburg, MS.

NatureServe. 2020. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available: http://explorer.natureserve.org. (Accessed: 21 July 2020).

Oliver, C.D., E.C. Burkhardt, and D.A. Skojac. 2005. The increasing scarcity of red oaks in Mississippi River floodplain forests: influence of the residual overstory. Forest Ecology and Management 210: 393-414.

Oliver, J.M. personal communication. State Forester (Retired), USDA Natural Resources Conservation Service, Murfreesboro, TN.

Pringle, H.C., III, L. Falconer, D.K. Fisher, and L.J. Krutz. 2017. Initiation of furrow irrigation in corn on a Dundee/Forestdale silty clay loam soil with and without deep tillage. Applied Engineering in Agriculture 33(2): 205-216.

Putnam, J.A. 1951. Management of bottomland hardwoods. U.S. Department of Agriculture, Forest Service, Southern Forest Experiment Station, Occasional Paper 116.

Putnam, J.A. and H. Bull. 1932. The Trees of the Bottomlands of the Mississippi River Delta Region, U.S. Department of Agriculture, Forest Service, Southern Forest Experiment Station, Occasional Paper 27.

Putnam, J.A., G.M. Furnival, and J.S. McKnight. 1960. Management and inventory of southern hardwoods. USDA Forest Service. Agriculture Handbook Number 181. 108 p.

Rhodes, G.N., Jr., G.K. Breeden, G. Bates, and S. McElroy. 2005. Hay crop and pasture weed management. University of Tennessee, UT Extension, Publication PB 1521-10M-6/05 (Rev). Available: https://extension.tennessee.edu/washington/Documents/hay_crop.pdf.

Rittenhour, T.M., M.D. Blum, and R.J. Goble. 2007. Fluvial evolution of the Lower Mississippi River Valley during the last 100 k.y. glacial cycle: Response to glaciation and sea-level change. Geological Society of America Bulletin 119: 586-608.

Saucier, R.T. 1994. Geomorphology and Quaternary geologic history of the Lower Mississippi Valley. Volumes I (report) and II (map folio). U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS.

Shen, Z., T.E. Tornqvist, W.J. Autin, Z.R.P. Mateo, K.M. Straub, and B. Mauz. 2012. Rapid and widespread response of the Lower Mississippi River to eustatic forcing during the last glacial-interglacial cycle. Geological Society of America Bulletin 124: 690-704.

Smith, R.D. and C. Klimas. 2002. A regional guidebook for applying the hydrogeomorphic approach to assessing wetland functions of selected regional wetland subclasses, Yazoo Basin, Lower Mississippi River Alluvial Valley. ERDC/EL TR-02-4, U.S. Army Engineer Research and Development Center, Vicksburg, MS.

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Stanturf, J.A., S.H. Schoenholtz, C.J. Schweitzer, and J.P. Shepard. 2001. Achieving restoration success: myths in bottomland hardwood forests. Restoration Ecology 9(2): 189-200.

Stevens, G. and H. Krusekopf. 2020. Delta soils of Southeast Missouri. Publication No. G9011. University of Missouri Extension, Columbia, MO. Available: https://extension.missouri.edu/publications/g9011 (Accessed: 21 February 2021).

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[USDA-NRCS] United States Department of Agriculture, Natural Resources Conservation Service. 2006b. Soil Survey of Leflore County, Mississippi. 281 p. Available: https://archive.org/details/usda-soil-survey-of-leflore-county-mississippi (Accessed: 13 August 2018).

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[USDA-SCS] United States Department of Agriculture, Soil Conservation Service. 1961. Soil Survey of Issaquena County, Mississippi. Series 1959, No. 2. Available: https://archive.org/details/usda-soil-survey-of-issaquena-county-mississippi (Accessed: 16 January 2018).

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Contributors

Barry Hart
Rachel Stout Evans

Approval

Charles Stemmans, 6/10/2025

Acknowledgments

We would like to express our sincere appreciation to the MLRA 131A Technical Team for their assistance and input in the development of this report. Special recognition is owed to Tom Foti (Ecologist, Arkansas Natural Heritage Commission, Retired) and Henry Langston (Wetland Ecologist, Arkansas Department of Transportation, Retired) for their time, personal travel expenses, and willingness to share their vast knowledge of the region. Their assistance with field reconnaissance, identifying sites and locations for investigating, and verifying ecological factors across multiple Mississippi River basins has led to a deeper understanding of the ecological sites and their associated states and community phases in the Southern Mississippi River Alluvium.

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	08/16/2026
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 F131AY203AR

St. Francis - Wet Transitional Backswamp Forest

Last updated: 6/10/2025 Accessed: 08/16/2026

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General information

MLRA notes

LRU notes

Classification relationships

Ecological site concept

Associated sites

Similar sites

Figure 1. Distribution of F131AY203AR.

Table 2. Dominant plant species

Natural Resources
Conservation Service

Last updated: 6/10/2025
Accessed: 08/16/2026