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Ecological site F131AY405LA

Tensas Basin - Somewhat Poorly Drained Bottomland Hardwoods

Last updated: 6/10/2025
Accessed: 08/29/2026

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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, 2006).

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, 2006).

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., 2011).

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

The Tensas Basin subregion of the MLRA, which this site is delineated within, is in the southern portion of MLRA 131A west of the Mississippi River in Louisiana and Arkansas. The Arkansas River provides the northern boundary, the Red River and the Delta Basin provide the southern boundary, the Mississippi River main line levee is the eastern boundary and the west is bounded by the Western Gulf Coastal Plain (MLRA 133B) and the Macon Ridge Loess (MLRA 134). It is in the Mississippi Alluvial Plain Section of the EPA Level IV Ecoregions in sub-sections 73a - Northern Holocene Meander Belts, portions of 73d - Northern Backswamps, portions of 73k - Southern Holocene Meander Belts, portions of 73l - Southern Pleistocene Valley Trains and portions of 73m - Southern Backswamps. The dissected plains in this portion of the MLRA have mixed soil mineralogy having influences from much of the drainage area of the Mississippi River, including the Arkansas River drainage area.

As mentioned previously, this subregion’s southern extent is found at the Red River where the Old River Control Structures regulate the flows of the Mississippi, Red, and Atchafalaya Rivers. Additional components include the river levee systems which further regulate the flows and flooding of these rivers and their tributaries. These man-made constraints to the system have substantially altered the hydrologic functions of the sites found within the whole of MLRA 131A. Areas within the confines of the levee systems, the unprotected areas, have increased frequency, duration, depth, and force of flooding. The areas outside of the levee systems, the protected areas, have reduced total flooding other than catastrophic events. These hydrologic alterations have changed ecological sites within the MLRA to where attempts at describing historic communities are at best scientific concepts, so most sites are described based on current regimes.

This area once consisted entirely of bottomland hardwood deciduous forests, mixed hardwood and cypress swamps. The major tree species in the native plant communities in the areas of bottomland hardwoods formerly were and currently are water oak, Nuttall oak, cherrybark oak, native pecan, red maple, sweetgum, eastern cottonwood, and hickory. The major tree species in the native plant communities in the swamps formerly were and currently are bald cypress, water tupelo, water oak, green ash, red maple, and black willow. The important native understory species are palmetto, greenbrier, wild grape, and poison ivy in the areas of bottomland hardwoods and buttonbush, lizardtail, waterlily, water hyacinth, sedges, and rushes in the swamps.

Some of the major wildlife species in this area are white-tailed deer, feral hogs, red fox, coyote, rabbit, gray squirrel, American alligator, water turtles, water snakes, frogs, otters, beavers, armadillo, crawfish, wild turkey, mourning doves, ducks, and geese. Fishing is mainly in oxbow lakes, rivers, and bayous. The species of fish in the area include largemouth bass, smallmouth bass, catfish, drum, bluegill, gar, and yellow perch.

Classification relationships

Major Land Resource Area (MLRA) and Land Resource Unit (LRU) (USDA-NRCS, 2006) MLRA 131A Southern Mississippi River Alluvium

EPA Level IV Ecoregion (portions of 73a - Northern Holocene Meander Belts, 73d - Northern Backswamps, 73i - Arkansas/Ouachita River Backswamps, 73m - Southern Backswamps and 73K Southern Holocene Meander Belts, of the Southern Mississippi River Alluvium Major Land Resource Area.)

The Natural Communities of Louisiana - (Louisiana Natural Heritage Program - Louisiana Department of Wildlife and Fisheries) - Bottomland Hardwood Forest

Foti et al. 2011. Potential Natural Vegetation of the Mississippi Alluvial Valley Tensas Basin - Not a direct one to one relationship between concepts and PNV Classification, however PNV concepts are very useful in informing the site concepts. This site is similar to the some of the "Flats" PNV designations.

Ecological site concept

Bottomland forests of this ecological site are generally higher in elevation and occur above the regular flooding frequency of the adjoining poorly drained sites. Specifically, the site occupies positions that are intermediate to the higher, better drained areas and the lower, wetter toeslopes of natural levees and meander scroll ridges. The site's position likely supports a gradation or overlapping of vegetation types consisting of components preferring drier conditions and species more tolerant of wetter environments.

The soils of this site are a little more coarsely textured than the lower poorly drained soils which improves the internal drainage and will provide opportunities for species that will favor better drainage to thrive. This site typically sheds precipitation, however at high stream flows can become inundated. Slopes on this site range from 0 to 3 percent, are generally around 0.5 percent

Hydrology is a major driver of this ecological site. Although disconnected from the Mississippi River via flood control structures, significant inflow into this site may occur from local waterways in addition to backwater flooding from tributaries to the Mississippi River. In the event of a catastrophic failure of the levee system, this area would be impacted by direct flows from the Mississippi River.

Areas are on flood plains in portions of Level IV EPA Ecoregions 73a - Northern Holocene Meander Belts, 73d - Northern Backswamps, 73i - Arkansas/Ouachita River Backswamps, 73m - Southern Backswamps and 73K - Southern Holocene Meander Belts, of the Southern Mississippi River Alluvium Major Land Resource Area. Located within the central western portion of the MLRA is the Tensas Basin which extends from approximately where the Arkansas River influence begins within the MLRA to the Red River to the south. Of note, this site occurs on the “protected” side of the extensive Mississippi River levee system and is distinguished from similar landforms within the “batture lands” (i.e., the alluvial land between the river channel and the constructed levee system).

Associated sites

F131AY402LA	Tensas Basin - Poorly Drained Backswamp The poorly drained back swamp site is the next lower site on the local landscape. There is a transition between these sites that is gradual in some locations.
F131AY406LA	Tensas Basin - Natural Levees and Ridge Hardwoods The natural levee and ridge site is the next higher site on the local landscape and there is a transition between these sites that is gradual in some locations.

F131AY402LA

Tensas Basin - Poorly Drained Backswamp

The poorly drained back swamp site is the next lower site on the local landscape. There is a transition between these sites that is gradual in some locations.

F131AY406LA

Tensas Basin - Natural Levees and Ridge Hardwoods

The natural levee and ridge site is the next higher site on the local landscape and there is a transition between these sites that is gradual in some locations.

Similar sites

F131AY201AR	St. Francis - Wet Clayey Backswamp Flat Is a similar site in a similar landscape position, but would be more clay soils. The difference is the St. Francis Basin site is found north of the Arkansas River in the Mississippi River Alluvium and this site is found further south.
F131AY213AR	St. Francis - Recent Moderately Wet Natural Levee and Meander Scroll Forest Is a similar site in a similar landscape position. The difference is the St. Francis Basin site is found north of the Arkansas River in the Mississippi River Alluvium and this site is found further south.
F131AY307MS	Yazoo - Old Moderately Wet Natural Levee and Meander Scroll Ridge Forest Is a similar site in a similar landscape position. The difference is the Yazoo Basin site is found east of the Mississippi River in the Mississippi River Alluvium and this site is found to the west of the river.
F131AY311MS	Yazoo - Recent Moderately Wet Natural Levee and Meander Scroll Ridge Forest Is a similar site in a similar landscape position. The difference is the Yazoo Basin site is found east of the Mississippi River in the Mississippi River Alluvium and this site is found to the west of the river.
F131AY503LA	Delta Plain - Somewhat Poorly Drained Bottomland Hardwoods The Delta Basin SWPD Bottomland site will occupy a similar position on the landscape however it will be found further south in the MLRA below where the Red River enters the MLRA.
F131AY403LA	Tensas Basin - Poorly Drained Ridge and Swale Complex The Tensas Basin - Poorly Drained Ridge and Swale Complex will have similarities in the ridge portion of that concept, having the same drainage class and similar vegetation.

Figure 1. 131AY405 ES Extent Map

Table 2. Dominant plant species

Tree	(1) Celtis laevigata (2) Ulmus americana
Shrub	Not specified
Herbaceous	Not specified

Download full description

Physiographic features

The Tensas Basin is located in the Mississippi River Alluvial Plain south of the Arkansas River and north of the Red River in northeast Louisiana and southeast Arkansas; it is about 180 miles in length. The basin is bounded by the Macon Ridge (MLRA 134) and uplands south of Sicily Island on the west, and the present Mississippi River meander belt on the east. The Tensas Basin is quite narrow, but widens steadily to the latitude of Vicksburg, and then varies in width between 25 and 45 miles. This portion of the MLRA is greatly affected by changes in hydrology over time, both natural and anthropogenic forces. The landscape was built by the flooding of the Mississippi River with influences of its drainage basin and is characterized entirely by Holocene meander belt and backswamp deposits.

This site occurs on low natural levees and meander scroll ridges in Mississippi River meander belts.

Table 3. Representative physiographic features

Landforms	(1) Flood plain (2) Natural levee (3) Ridge
Runoff class	Very low to negligible
Flooding duration	Very long (more than 30 days)
Flooding frequency	None to frequent
Ponding frequency	None
Elevation	0 – 180 ft
Slope	0 – 3 %
Ponding depth	0 in
Water table depth	0 – 47 in
Aspect	Aspect is not a significant factor

Climatic features

Northeast Louisiana and southeast Arkansas have a warm, humid climate, with fairly long summers and relatively short winters. The result is a long growing season and abundant plant growth. Water is a definitive part of the landscape, largely due to the combination of low elevation and fairly abundant rainfall in most years. Annual precipitation is fairly well distributed throughout the year, however there is a typical pattern of dryer weather during the summer, typically July through mid September with scattered rainfall events.

In the warmer season (and throughout much of the year), winds from the south convey moisture from the gulf leading to humid, semitropical conditions that are favorable for afternoon thunderstorms. These storms produce an average of about 25 percent of the area’s annual precipitation and are at times accompanied by locally destructive winds. An additional hazard of concern during late summer through early fall are tropical cyclones. 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 Tensas 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.

The following climatic data are averages from the weather stations listed below. Temperature and precipitation may vary considerably from that listed for each month. Site specific weather data should be used for land management decisions. For site specific weather conditions, obtain data from a weather station close to the site.

Information can be accessed from specific weather stations at http://www.wrcc.dri.edu/coopmap/ or http://www.wrcc.dri.edu/summary/climsmla.html.

Table 4 Representative climatic features

Frost-free period (characteristic range)	220-230 days
Freeze-free period (characteristic range)	250-260 days
Precipitation total (characteristic range)	60-60 in
Frost-free period (actual range)	220-230 days
Freeze-free period (actual range)	250-270 days
Precipitation total (actual range)	60-60 in
Frost-free period (average)	230 days
Freeze-free period (average)	260 days
Precipitation total (average)	60 in

Characteristic range

Actual range

Bar

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Figure 1. Monthly precipitation range

Characteristic range

Actual range

Bar

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Figure 2. Monthly minimum temperature range

Characteristic range

Actual range

Bar

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Figure 3. Monthly maximum temperature range

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Figure 4. Monthly average minimum and maximum temperature

Figure 5. Annual precipitation pattern

Figure 6 Annual average temperature pattern

Climate stations used

(1) ST JOSEPH 3 N [USC00168163], Newellton, LA
(2) TALLULAH [USC00168923], Tallulah, LA
(3) JONESVILLE LOCKS [USC00164739], Jonesville, LA
(4) LAKE PROVIDENCE [USC00165090], Lake Providence, LA

Influencing water features

This site is in an undulating landscape which receives and sheds water. Flow may be received from adjacent landscapes, upstream sources, and from backwater flooding.

Wetland description

Cowardin System:<br />
System - Palustrine<br />
Class - Forested Wetland

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 the Supporting Information section of this description to determine if another site may be a better fit for your area of interest.

The principal (or modal) soils of this site are very deep, somewhat poorly drained soils that formed in loamy alluvium on the intermediate backslope positions on natural levees and on low ridges of meander scrolls in recent Mississippi River meander belts. Dominant slope gradient is between 0 and 2 percent, but may range to a high of 3 percent on undulating meander scroll ridges. Permeability is moderately rapid to very slow, and runoff is medium to slow.

The Commerce and Dundee are the modal soils for this site, other soil series associated with this site are Tensas, Newellton, and Bowdre. Commerce (fine-silty, mixed, superactive, nonacid, thermic Fluvaquentic Endoaquepts) soil series occur on younger, more recent natural levees and meander scroll ridges of the Mississippi meander belts. Commerce soils can have a perched saturated zone above the clayey layers, but they also have saturated layers beneath them. Reaction in Commerce soils are slightly to moderately alkaline from the surface through the subsoil. Dundee soils (fine-silty, mixed, active, thermic Typic Endoaqualfs) occur on older natural levees of former channels and older meander scroll ridges of the Mississippi River. Reaction in Dundee soils are extremely acid to moderately acid from the surface through the subsoil. Due to artificial draining for intensive agricultural use, the water tables in both Commerce and Dundee range from 3.5 to 6 feet below the surface in drained areas. In undrained areas, or adjacent to the Mississippi River levee, an apparent water table is about 1.5 to 3.5 feet below the surface during winter and spring months.

Bowdre soils (clayey over loamy, smectitic, thermic Fluvaquentic Hapludolls) and Newellton soils (clayey over loamy, smectitic over mixed, superactive, nonacid, thermic Fluvaquentic Epiaquepts) occur on lower positions on younger, more recent natural levees, while Tensas soils (fine, smectitic, thermic Chromic Vertic Epiaqualfs) are located on older, low natural levees. Bowdre, Newellton, and Tensas formed in clayey Mississippi River alluvium overlying loamy alluvium.

Table 5. Representative soil features

Parent material	(1) Alluvium
Surface texture	(1) Loam (2) Silty clay loam (3) Silty clay (4) Silt loam (5) Clay
Family particle size	(1) Loamy
Drainage class	Somewhat poorly drained
Permeability class	Very slow to moderately rapid
Soil depth	80 in
Surface fragment cover <=3"	0 – 1 %
Surface fragment cover >3"	Not specified
Available water capacity (0-40in)	4.9 – 8.4 in
Calcium carbonate equivalent (0-40in)	Not specified
Electrical conductivity (0-40in)	Not specified
Sodium adsorption ratio (0-40in)	Not specified
Soil reaction (1:1 water) (0-40in)	3.5 – 8.4
Subsurface fragment volume <=3" (Depth not specified)	Not specified
Subsurface fragment volume >3" (Depth not specified)	Not specified

Ecological dynamics

Bottomland forests of this ecological site are generally higher in elevation and occur above the regular flooding frequency of the adjoining poorly drained sites. Specifically, the site occupies positions that are intermediate to the higher, better drained areas and the lower, wetter toeslopes of natural levees and meander scroll ridges. The site's position likely supports a gradation or overlapping of vegetation types consisting of components preferring drier conditions and species more tolerant of wetter environments.

The soils of this site are a little more coarsely textured than the lower poorly drained soils which improves the internal drainage and will provide opportunities for species that will favor better drainage to thrive. This site typically sheds precipitation, however at high stream flows can become inundated. Slopes on this site range from 0 to 3 percent, are generally around 0.5 percent

Hydrology is a major driver of this ecological site. Although disconnected from the Mississippi River via flood control structures, significant inflow into this site may occur from local waterways in addition to backwater flooding from tributaries to the Mississippi River. In the event of a catastrophic failure of the levee system, this area would be impacted by direct flows from the Mississippi River.

Areas are on flood plains in portions of Level IV EPA Ecoregions 73a - Northern Holocene Meander Belts, 73d - Northern Backswamps, 73i - Arkansas/Ouachita River Backswamps, 73m - Southern Backswamps and 73K - Southern Holocene Meander Belts, of the Southern Mississippi River Alluvium Major Land Resource Area. Within the central western portion of the MLRA in the Tensas Basin which extends from approximately where the Arkansas River influence begins within the MLRA and to the Red River to the south. Of note, this site occurs on the “protected” side of the extensive Mississippi River levee system and is distinguished from similar landforms within the “batture lands” (i.e., the alluvial land between the river channel and the constructed levee system).

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	-	Wind or water Force causing canopy gaps.
T*-3	-	Avulsion - Change in river or channel course
T1B	-	Clear and established the desired Community.
T1B	-	Clear and established the desired Community.
T1B	-	Clear and established the desired Community.
T1B	-	Clear and established the desired Community.
T1C	-	Manipulation of species composition.
T2A	-	Regeneration of BLH species.
T*-3	-	Avulsion - Change in river or channel course
T*-5	-	Establish desired forage species and manage for grazing.
T*-6	-	Plant or natural regeneration of woody and/or herbaceous species.
T*-8	-	Establish Trees & Herbaceous species and manage for multi use.
T*-9	-	Dedicate area to Urban development, Infrastructure and Protection Levees.
T*-4	-	Establish and manage crop rotation.
T*-6	-	Plant or natural regeneration of woody and/or herbaceous species.
T*-8	-	Establish Trees & Herbaceous species and manage for multi use.
T*-9	-	Dedicate area to Urban development, Infrastructure and Protection Levees.
T6-7	-	Manage succession for historic community.
T*-9	-	Dedicate area to Urban development, Infrastructure and Protection Levees.
T*-4	-	Establish and manage crop rotation.
T*-5	-	Establish desired forage species and manage for grazing.

State 1 submodel, plant communities

1.1. Mixed Bottomland Hardwood – transitional across wetness regimes

State 2 submodel, plant communities

2.1. Wind or Water Throws of Trees (Food Plot)

State 3 submodel, plant communities

3.1. Catastrophic River Change in Channel (Avulsion)

State 4 submodel, plant communities

4.1. Conservation Management

4.2. Transitional Conservation Management

4.3. Conventional Management

4.1A	-	Soil disturbance (Tillage) which reduces Soil Health.
4.1B	-	Conventional tillage, seeding, and fertility Management for crops.
4.2A	-	No-till, Cover crops, Reduced Till - Soil Health Improvements.
4.2B	-	Conventional tillage, seeding, and fertility Management for crops.
4.3A	-	No-till, Cover crops, Reduced Till with Soil Health Improvements as a goal.

State 5 submodel, plant communities

5.1. Managed Monoculture Grassland

SWAPAEH

5.2. Mixed Species Managed System

SWAPAEH

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 unwanted species.
5.2B	-	Species Management without overseeding.
5.3A	-	Seeding, fertilizing, management/ removal of unwanted species.
5.3B	-	Seeding and/or Management for desired species composition.
5.3C	-	Lack of disturbance: No or minimal Mowing, burning, herbivory or Brush Mgmt. and/or Plant or natural regeneration of woody species.
5.4A	-	Brush management / removal of unwanted plants.

State 6 submodel, plant communities

6.1. Old Field or planted hardwoods

State 7 submodel, plant communities

7.1. Restored Bottomland Hardwood Community

State 8 submodel, plant communities

8.1. Pecan Orchard or similar managed Woody and Herbaceous complex

State 9 submodel, plant communities

9.1. Urban

9.2. Protection Levees

State 10 submodel, plant communities

10.1. Bottomland Hardwoods

10.2. High graded harvested timber

10.1A	-	Harvest timber selecting highest value timber.
10.2A	-	Manage succession or manipulate species composition to improve value.

State 1
Historic Community Bottomland Hardwood

Historic stand of mixed bottomland hardwood species.

Community 1.1
Mixed Bottomland Hardwood – transitional across wetness regimes

Mixed Bottomland Hardwood – they transition across wetness regimes containing Sugarberry, American Elm, Ash, Components of -Cherrybark Oak, Water Oak, Bitternut Hickory, Cedar Elm, Palmetto, Rivercane, Sweetgum, Persimmon, Black Gum, Pawpaw.
In minor streams areas Willow Oak, & Nutall Oak will pickup in the stand also.

State 2
Canopy Gap

This state consists of forest canopy openings that are created by catastrophic disturbances, allowing sunlight to reach understory strata and ground surfaces. Depending on local conditions and disturbance regime and intensity, a continuum or range of successional stages and community structure (physiognomy) is represented. Provisionally, this state includes seral stages ranging from recent disturbances that consist mainly of sparse herbaceous cover over mostly bare soil to the regeneration of woody species among a dense herbaceous cover (early stand initiation stage) to the initial stem exclusion stage where woody growth overtops and shades out the herbaceous stratum. In future ecological site development efforts, multiple community phases that describe the composition and progression from one stage to the next may be warranted for specifying management strategies and actions.

Community 2.1
Wind or Water Throws of Trees (Food Plot)

Some of the potential mechanisms to create canopy gaps in a forest community are water and/or wind from a storm or catastrophic event. The site can be affected by both forces simultaneously during a tropical storm, hurricane or by similar events as well as by river flood events. An anthropogenic force that could cause similar state conditions would be the creation of food plots in managed hunting locations. Food plots may function similarly to cropland or pasture states depending on how they are managed, but initially they may be similar to this state. However, the transition of food plots to wooded conditions may not transition similarly to agricultural production fields depending on size and proximity to the natural community affecting the seed source. If an opening is large enough or adjacent seed sources are not present, the site will progress through succession similar to agriculture fields.

State 3
New River Run & Floodplain

Catastrophic river change in channel (Avulsion).

Community 3.1
Catastrophic River Change in Channel (Avulsion)

When the river changes courses, which is caused by multiple factors, this site will be affected in potentially many ways. This site may become the location of the new channel when the river re-occupies an older course or that of another river. Conversely when the river changes course and abandons previous backswamps the site may lose sediment and water inputs and become drier, which will allow the fluid sediments to consolidate. This State potentially has more phases compared to all other Ecological Site states in this sub-region.

State 4
Cropland

This state represents a crop production field. Annual plantings for forage production would also be included in this phase, which may include cool season annual grasses and legumes and warm season forage species. Vegetable crops are grown on this site and are generally on a small scale. Rice, soybeans, and corn are dominant crops and can be planted in fields with adequate management. Other row crop species have been produced on these sites. Often two or more crops will be grown in a multiyear rotation, this breaks pest cycles and some crops produce higher amounts of residue, which is left on the soil to improve soil health. Maintenance of monoculture crop stands also requires the control of unwanted species, which will require Pest Management and Nutrient Management to maintain the needed fertility for production of the desired species. Refer to E-Field Office Technical Guide and the local NRCS Field Office for management assistance.

The site may be established to crop species and utilized for production. Maintenance of the hydrologic control systems must be continued to maintain production, and if maintenance is abandoned or lost, wet conditions may return which will reduce utilization of the land for crop production. Conditions, even with control, may only allow production on an irregular basis or uneven production.

This site is an undulating landscape, so it is variably suited for crop production due to potential wetness and the variable textures which will present inconsistencies in production across a field. The site can be managed in cropland without leveling however production efficiency may be reduced especially when irrigation is utilized.

Careful planning considerations should be made when considering land leveling on this site to mitigate the multiple soil and drainage impacts that will occur. When the site is land leveled, production limitations can occur. Removing the better drained, coarse materials from the higher areas and depositing them in the lower positions may adversely impact production by introducing high variability of infiltration rates, unfavorable soil chemistry, and physical property issues such as available water capacity. Additional impacts often include a reduction in organic matter content in the surface layer. Mitigation measures to offset this impact (e.g., applying or introducing organic residues and materials in the surface layer) may need to be implemented to meet production goals. When the site is to be irrigated for crop production, land leveling can improve irrigation efficiencies and water use, which may justify the implementation. However, this change in the landscape will have other impacts that must be considered.

Community 4.1
Conservation Management

This cropland phase utilizes long term continuous conservation management systems including reduced till and cover crops, no-till with cover crops, and perennial cropping systems. Indicators of these systems take place in the soil and impacts how it functions. The state change can only be quantified using soil health indicator tests. The above-ground crop growth is not the best tracking mechanism for this phase. Implementation of tillage even after long term no-till will reset the system back to conventional cropping systems, however returning to a conservation management system is achievable. There are instances where, due to climatic conditions in a given crop year, tillage may be considered and/or needed to repair previous damage. These instances should be critically considered prior to implementing tillage if the desired outcome is aesthetics opposed to production.

Critical conservation practices associated with this phase include Cover Crops, No-Till, and reduced tillage as the bedrock practices. There could also be associated supporting and site-specific practices that are needed to address specific conservation needs in a given management unit.

Community 4.2
Transitional Conservation Management

This cropland phase is a common scenario and could be in a continuous ‘transitional’ phase of conservation management state forever. Getting past years 1-2 will reduce the need to apply pesticides that call for bare soil for activation. Perennial crop species could be in a continuous transitional phase where intense tillage is implemented at the time of planting and then reduced tillage during the rotation. Planted forage crops could also be included in this phase when part of a crop rotation, as well as when part of a rotation where reduced tillage is implemented for one crop and then tillage is utilized for another crop in the rotation.

Conservation practices are included with this phase and include Nutrient Management, Pest Management, Reduced Till, Strip Till and the inclusion of Cover Crops. There could also be associated supporting and site-specific practices that are needed to address specific conservation needs in a given management unit.

Community 4.3
Conventional Management

This cropland phase is typical conventional cropland where tillage is implemented as an annual part of the production system. This system is productive and will require the utilization of conservation practices such as Nutrient and Pest Management to address fertility needs and pest concerns within the crop production cycle. This phase may occur when tillage is implemented to address damage due to weather conditions during a previous crop cycle in a conservation management system and the intention is to return to the conservation management system.

There could also be associated, supporting, and site-specific practices that are needed to address specific conservation needs in a given management unit. Specific needs may include grade stabilization structures to control gully erosion, grassed waterways to trap sediment from sheet and rill erosion, or reduced tillage.

Pathway 4.1A
Community 4.1 to 4.2

Soil disturbance (tillage) which reduces soil health.

Pathway 4.1B
Community 4.1 to 4.3

Conventional tillage, seeding, and fertility management for crops.

Pathway 4.2A
Community 4.2 to 4.1

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

Pathway 4.2B
Community 4.2 to 4.3

Conventional tillage, seeding, and fertility management for crops.

Pathway 4.3A
Community 4.3 to 4.2

No-till, cover crops, reduced tillage with soil health improvements as a goal.

State 5
Converted State - Pasture or Grassland

This site is generally considered not suited for grazing due to flooding and wetness. When the site hydrology has been altered mechanically by the construction of levees, water control structures, and potentially pumps, forage species may be established, and the site utilized for grazing. Maintenance of the hydrologic control must be continued to maintain production and if control is abandoned or lost, site conditions may return to excessively wet conditions which will prevent utilization of the land for forage production. Conditions even with control may only allow forage production on an irregular basis. Additionally, adjacent higher elevation areas or protected areas may be needed for the storage of harvested forage or holding of livestock when wet or flooded conditions occur. Some forage operations on this site may experience none to multiple extreme wetness events in a single year that will require preplanning and resources to meet the needs of the livestock.

This state is characterized by a monoculture or a mixture of forage species planted or allowed to establish from naturalized species managed for forage production or as herbaceous ground cover.

Community 5.1
Managed Monoculture Grassland

Typically, this phase is characterized by planting forage species for hay production. Forage plantings generally consist of a single grass species. Introduced native and/or non-native forage species can be seeded. Forage is usually harvested as hay or haylage, although grazing may occur periodically. These sites are highly 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 management and nutrient management to maintain the needed fertility for the production of the species.

Generally, application of fertilizer and lime, is needed to establish and maintain improved desirable pastures. The exception to this is bahiagrass and common bermudagrass, which can be sustained under natural fertility and pH levels. Introduced legumes require higher pH, phosphorus, and potassium levels than most grasses. Introduced grasses, such as hybrid bermudagrass, require a higher level of sustained fertility, pH above 6.0, and good surface drainage to persist. Implementing prescribed 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 other site-specific facilitating practices.

Dominant plant species

Bermudagrass (Cynodon dactylon), grass
bahiagrass (Paspalum notatum), grass
dallisgrass (Paspalum dilatatum), grass

Dominant resource concerns

Ephemeral gully erosion
Classic gully erosion
Compaction
Organic matter depletion
Ponding and flooding
Plant productivity and health
Plant structure and composition
Feed and forage imbalance
Inadequate livestock water quantity, quality, and distribution

Figure 7. Annual production by plant type (representative values) or group (midpoint values)

Table 6. Annual production by plant type

Plant type	Low (lb/acre)	Representative value (lb/acre)	High (lb/acre)
Grass/Grasslike	2000	6000	10000
Total	2000	6000	10000

Figure 8. Plant community growth curve (percent production by month). LA0006 , Common Bermudagrass. Common Bermudagrass.

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
J	F	M	A	M	J	J	A	S	O	N	D
			3	15	32	31	12	5	2

Community 5.2
Mixed Species Managed System

This community is characterized by mixed species composition of grasses and legumes, which is planted or naturally established. Typically, perennial warm-season grasses are the foundation of the stand which is periodically overseeded with adapted cool-season forages to extend 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 collection 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 heights, timing, and stocking rates. Supporting or facilitating practices including fences, water lines and watering facilities could be part of the system that maintains this phase.

Dominant resource concerns

Ephemeral gully erosion
Classic gully erosion
Compaction
Ponding and flooding
Seasonal high water table
Plant productivity and health
Plant pest pressure
Feed and forage imbalance
Inadequate livestock shelter
Inadequate livestock water quantity, quality, and distribution

Community 5.3
Mixed Species, Non-seeded

This community is characterized by a stand where mixtures of native and naturalized non-native species occur. This could also include abandonment of cropping (i.e., idle cropland) that is not being utilized for forage production. This state represents low inputs after cropping, no initial seeding of pasture species, or periodic overseeding of adapted forage species. Forage is usually grazed and/or harvested as stored forage, hay or haylage. Commonly established species may include Bermudagrass, Bahiagrass, Vasey grass, and carpet grass. This state is productive, and forage and grazing management can maintain forage stands and protect soils from excessive runoff and erosion. A common peril associated with this phase is overgrazing which favors less productive and less palatable weedy species, especially in areas where livestock congregate. Proper stocking rates and/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 will develop deeper root systems and greater leaf area allowing for the capture of greater solar energy for plant growth. Conversely, when plants are not allowed to recover adequately, root development will be restricted and forage and biomass production will be reduced. Maintenance of grass stands also requires Pest Management for control of unwanted weedy and woody species.

Community 5.4
Early Woody Succession

This community is characterized by a diverse species composition of grasses and forbs with an increasing composition of woody species (native and non-native) that are immature and low stature. If this community phase is not managed, and no brush management measures are taken, the plant community will transition to the Woody Encroached State (6). Control of woody species will require the input of extensive resources to return to a Grassland or Cropland State. This phase is generally limited in woody species composition and size to the point where normal agricultural equipment is no longer able to return the site to a cropland phase by mowing or disking. When the threshold is crossed to where the stem diameter exceeds 2 - 3 inches and the cover density exceeds 100 - 300 stems per acre, the site has transitioned to the Woody Encroached State.

If the restored hardwood community is desired, proper management is required. This phase can be beneficial habitat for some wildlife species. Woody invasive species grow quickly and can be difficult and expensive to control. Some invasive woody species, such as tallow trees (Triadica sebifera), will invade and grow to produce seeds in as few as 3 years.

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 unwanted 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 unwanted 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 minimal mowing, burning, herbivory or brush management. And/or plant or natural regeneration of woody species.

Pathway 5.4A
Community 5.4 to 5.3

Brush management / removal of unwanted plants.

State 6
Woody encroached

Community 6.1
Old Field or planted hardwoods

This phase occurs when cropland or pastureland has been abandoned and allowed to naturally regenerate or when artificial regeneration is planned to re-introduce hardwoods to the site. This state will have succession similar to the Canopy Gap State of the historic community, however species composition may be very different depending on the available seed source. When this occurs from a Cropland or Pasture state species composition may be dominated by introduced species, but desired hardwood species can be established to regenerate the state to that desired community.

State 7
Conservation Area

Restored Bottomland Hardwood Community.

Community 7.1
Restored Bottomland Hardwood Community

This phase occurs when cropland or pastureland has been regenerated to re-introduce hardwoods to the site. This state will have succession similar to the canopy gap state of the historic community where the hardwood canopy has begun to shade out herbaceous competition. Species composition may be very different depending on the local available seed source and species that are planted. Desired hardwood species can be established to reach the community that best fits the site conditions.

State 8
Silvopasture

Combination of a relatively open canopy of trees and herbaceous ground cover.

Community 8.1
Pecan Orchard or similar managed Woody and Herbaceous complex

This phase occurs when the site is planted to a mixture of tree species as in an orchard and herbaceous species for crop, hay, or pasture are established and maintained. This phase is common in the alluvial plain as pecan orchards, however other species may be utilized. The herbaceous production of this phase is generally similar to that of the pastured state however they may or may not be utilized as a forage crop, depending on needs and management. Agronomic crops similar to the cropland state could also be planted depending on the management.

State 9
Long-term Dedicated Lands

Dedicated alternative uses.

Community 9.1
Urban

This phase occurs when the site is dedicated to urban use of homes, roads, businesses and other similar uses. This state will have little likelihood of returning to another state or phase of the site, however small inclusion of alternatives states may be included within an area of urban lands. Refer to those sections of the description for those land uses.

Community 9.2
Protection Levees

This phase occurs when the site is utilized for the construction of protection levees. The primary purpose is to provide protection from flooding, however these areas are often utilized for forage production and are hayed or grazed by livestock. These areas generally have long-term easements or ownership by units of government and are unlikely to be converted to other land uses.

State 10
Forested

Hardwoods managed for timber production and other uses.

Community 10.1
Bottomland Hardwoods

This phase is characterized by a stand of hardwood species planted or allowed to regenerate from seed trees managed for wood production as well as other uses. This phase may not have been harvested.

This site fits into multiple Woodland Suitability Groups (WS) (2w5, 2w6 or 1w5) depending on the soil map unit. The first part of the symbol indicates the soils potential productivity related to the production of important trees, very high (1) and high (2). The second part, a letter, indicates the major kind of soil limitation, limitation of excessive water in or on the soil (w). The third part of the symbol, a numeral, indicates the kind of trees for which the soils are best suited and the severity of the hazard or limitation. The numerals 5 and 6 indicate moderate and severe limitations and suitability for broadleaf trees.

These groups would generally describe this site as having a range of productivity from very high to high, with moderate to severe limitations for wetness for the production of broadleaf species.

WS 2w5 is described as moderately wet, loamy and clayey soils with high potential productivity; moderate equipment limitations and slight to moderate seedling mortality due primarily to excess water; best suited for southern hardwoods. Site index for green ash 80, cottonwood 110, oaks and sweetgum 90. Grazing is not recommended. Potential is high for management of deer, turkey, squirrels and ducks.

WS 2w6 is described as wet, Clayey soils with high potential productivity, severe equipment limitations and moderate seedling mortality due primarily to excess water; Site index for green ash 80, cottonwood 100, oaks and sweetgum 90. Grazing is not recommended. Potential is high for deer, ducks, squirrels and moderately high for turkey.

WS 1w5 is described as moderately wet, loamy soils with very high potential productivity; moderate equipment limitations due primarily to excess water; best suited for southern hardwoods. Site index for green ash 80-100, cottonwood 100-120, oaks 90-100, sweetgum 110. Grazing is not recommended. Potential is high for management of deer, ducks, squirrels, and turkey.

Community 10.2
High graded harvested timber

This phase occurs when most or all of the high-valued timber and desirable trees have been removed. The residual stand is left with mostly poorly formed desirable species and undesirable trees. This state will have value for wildlife, however measures will need to be taken to manipulate composition and structure if timber production is the desirable land use. To achieve the desired timber production, the stand will require intense management to attain long term production goals. Management actions may necessitate the removal of undesirable competitors and poorly formed stems of desirable species; scheduled stand improvement actions at appropriate intervals; and artificial regeneration where needed. Targeted stands should be carefully evaluated and a thorough silvicultural plan developed far in advanced of any initiated action.

Pathway 10.1A
Community 10.1 to 10.2

Harvest timber selecting highest value timber.

Pathway 10.2A
Community 10.2 to 10.1

Manage succession or manipulate species composition to improve value.

Transition T1A
State 1 to 2

Wind or water force causing canopy gaps.

Transition T*-3
State 1 to 3

Avulsion - Change in river or channel course

Transition T1B
State 1 to 4

Clear and established the desired community.

Transition T1B
State 1 to 5

Clear and established the desired community.

Transition T1B
State 1 to 8

Clear and established the desired community.

Transition T1B
State 1 to 9

Clear and established the desired community.

Transition T1C
State 1 to 10

Manipulation of species composition.

Transition T2A
State 2 to 1

Regeneration of Bottomland Hardwood species.

Transition T*-3
State 2 to 3

Avulsion - Change in river or channel course

Transition T*-5
State 4 to 5

Establish desired forage species and manage for grazing.

Transition T*-6
State 4 to 6

Plant or natural regeneration of woody and/or herbaceous species.

Transition T*-8
State 4 to 8

Establish trees and herbaceous species and manage for multi use.

Transition T*-9
State 4 to 9

Dedicate area to urban development, infrastructure and protection levees.

Transition T*-4
State 5 to 4

Establish and manage crop rotation.

Transition T*-6
State 5 to 6

Plant or natural regeneration of woody and/or herbaceous species.

Transition T*-8
State 5 to 8

Establish trees and herbaceous species and manage for multi use.

Transition T*-9
State 5 to 9

Dedicate area to urban development, infrastructure and protection levees

Transition T6-7
State 6 to 7

Manage succession for historic community.

Transition T*-9
State 6 to 9

Dedicate area to urban development, infrastructure and protection levees.

Transition T*-4
State 8 to 4

Establish and manage crop rotation.

Transition T*-5
State 8 to 5

Establish desired forage species and manage for grazing.

Additional community tables

Table 7. Community 1.1 plant community composition

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

Table 8. Community 2.1 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 4.1 plant community composition

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

Table 11. Community 4.2 plant community composition

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

Table 12. Community 4.3 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 (%)
Grass/Grasslike
1	Warm Season Grass			2000–10000
	Bermudagrass	CYDA	Cynodon dactylon	2000–10000	–

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 7.1 plant community composition

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

Table 19. Community 8.1 plant community composition

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

Table 20. Community 9.1 plant community composition

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

Table 21. Community 9.2 plant community composition

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

Table 22. Community 10.1 plant community composition

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

Table 23. Community 10.2 plant community composition

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

Supporting information

Other references

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.

Aslan, A., W. J. Autin, and M. D. Blum. 2005. Causes of river avulsion: insights from the late Holocene avulsion history of the Mississippi River, USA. Journal of Sedimentary Research, 75(4), 650-664.

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.

Autin, W. J. 1996. Pleistocene stratigraphy in the southern Lower Mississippi Valley. Engineering Geology, 45(1), 87-112.

Blum, M.D., M.J. Guccione, D.A. Wysocki, P.C. Robnett, and E.M. Rutledge. 2000. Late Pleistocene evolution of the lower Mississippi River valley, southern Missouri to Arkansas. Geological Society of America Bulletin, 112(2), 221-235.

Broadfoot, Walter M. 1976. Hardwood suitability for and properties of important midsouth soils. Res. Pap. SO-127. New Orleans, LA: U.S. Department of Agriculture, Forest Service, Southern Forest Experiment Station. 84 p.

Brown, D. A., V. E. Nash, A. G. Caldwell, L. J. Bartelli, R. C. Carter, and O. R. Carter. 1970. A monograph of the soils of the southern Mississippi River Valley alluvium. Southern Cooperative Series Bulletin, 178, 112.

Chapman, S.S, G.E. Griffith, J.M. Omernik, J.A. Comstock, Beiser, M.C., and D. Johnson. 2004. Ecoregions of Mississippi, (color poster with map, descriptive text, summary tables, and photographs): Reston, Virginia, U.S. Geological Survey (map scale 1:1,000,000).

Cowardin, L. M., V. Carter, F. C. Golet, and E. T. LaRoe. 1979. Classification of wetlands and deepwater habitats of the United States. US Fish and Wildlife Service FWS/OBS, 79(31), 131.

Cowdrey, A. E. 1977. Land’s End: A history of the New Orleans District. US Army Corps of Engineers, and Its Lifelong Battle with the Lower Mississippi and Other Rivers Wending Their Way to the Sea.

Daigle, J.J., G.E. Griffith, J.M. Omernik, P.L. Faulkner, R.P. McCulloh, et al. 2006. Ecoregions of Louisiana (color poster with map, descriptive text, summary tables, and photographs): Reston, Virginia, U.S. Geological Survey (map scale 1:1,000,000).

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.

Ezell, A.W. 2016. Evaluating high-graded hardwood stands. Publication-Cooperative Extension Service, Mississippi State University (USA).

Fisk, H. N. 1944. Geological investigation of the alluvial valley of the lower Mississippi River: US Dept. Army, Mississippi River Comm.

Foti, T., C. Klimas, J. Pagan, and A. Keister. 2011. Potential natural vegetation of the Mississippi Alluvial Valley: Tensas Basin, Northeastern Louisiana. U.S. Fish and Wildlife Service, Lower Mississippi Valley Joint Venture; Vicksburg, MS.

Gardiner, E. S., and J. M. Oliver. 2005. Restoration of bottomland hardwood forests in Lower Mississippi Aluvial Valey, USA. In: Stanturf, JA; Madsen, P. eds. Restoration of boreal and temperate forests. Restoration of bottomland hardwood forests in the Lower Mississippi Alluvial Valley, USA Boca Raton, FL: CRC Press. 235-251.

Grigar, J., J.L. Hatfield, and R. Reeder, 2018. Transitional no-till: What is it and how does it differ from ‘true’no-till?. Crops and Soils 51, no. 6:28–36.

Kemp, K. 2000. The Mississippi Levee System and the Old River Control Structure. Available online: http://www.tulane.edu/~bfleury/envirobio/enviroweb/FloodControl.htm. Accessed 11/2018

Klimas, C.V. 1988. Forest vegetation of the leveed floodplain of the lower Mississippi River. Lower Mississippi River Environmental Program Report 11. US Army Corps of Engineers. Vicksburg, Mississippi.

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

Lentz, G. H. 1928. Summary of First Year's Hardwood Investigations in Louisiana. US Forest Service and Louisiana Division of Forestry
Lentz, G. H. 1929. Summary of First Year's Hardwood Investigations in Louisiana. Journal of Forestry, 27(5), 486-494.

McKnight, J.S., D.D. Hook, O.G. Langdon, and R.L. Johnson. 1981. Flood tolerance and related characteristics of trees of the bottomland forests of the southern United States. In Developments in Agricultural and Managed Forest Ecology. 11, pp. 29-69. Elsevier. https://www.srs.fs.usda.gov/pubs/ja/1980/ja_1980_mcknight_001.pdf (accessed 12 Oct. 2018)

Putnam, J. A., and H. Bull. 1932. The trees of the bottomlands of the Mississippi River Delta Region. US Department of Agriculture, Forest Service, Southern Forest Experiment Station, Occasional Paper, 27, 207.

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(5-6): 586-608.

Rogers, D. 2005. Evolution of the levee system along the Lower Mississippi River. University of Missouri-Rolla: Rolla, MO, USA. https://web.mst.edu/~rogersda/levees/Evolution%20of%20the%20Levee%20System%20Along%20the%20Mississippi.pdf. Accessed 10/2018.

Saucier, R. T. 1974. Quaternary geology of the lower Mississippi Valley (No. 6). Arkansas Archeological Survey.

Saucier, Roger T. 1994. Geomorphology and Quaternary Geologic History of the Lower Mississippi Valley, Volumes I & II. U.S. Army Corps of Engineers, Vicksburg, MS. (Available online: http://biotech.law.lsu.edu/climate/mississippi/sausier/sausier.htm)

Schumm, S. A., and W. J. Spitz. 1996. Geological influences on the Lower Mississippi River and its alluvial valley. Engineering Geology, 45(1-4), 245-261.

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(5-6): 690-704.

Theriot, R. F. 1992. Flood tolerance of plant species in bottomland forests of the southeastern United States. Ph.D. diss. University of Florida. Available online: http://ufdc.ufl.edu//AA00003281/00001

Turner, S., J. Welch, and N. Musso. 2010. The Atchafalaya National Heritage Area, Selected Level 0 Cultural Landscape Assessments. Suzanne Turner Associates LLC. Available online: http://www.atchafalaya.org/ckfinder/userfiles/files/CLA-Final.pdf

Tye, R. S., and J. M. Coleman. 1989. Depositional processes and stratigraphy of fluvially dominated lacustrine deltas: Mississippi delta plain. Journal of Sedimentary Research, 59(6).

[USACE] U.S. Army Corps of Engineers. 2004. Louisiana Coastal Area Comprehensive Coastwide Ecosystem Restoration Study. U.S. Army Corps of Engineers, New Orleans, LA. Available online: https://www.lca.gov/Library/ProductList.aspx?Prodtype=0&folder=1118.

[USACE] United States Army Corps of Engineers. 2017. The Mississippi Drainage Basin. U.S. Army Corps of Engineers, New Orleans District Website. Available: https://www.mvn.usace.army.mil/Missions/Mississippi-River-Flood-Control/Mississippi-River-Tributaries/Mississippi-Drainage-Basin/ (Accessed: 2017).

[USACE] U.S. Army Corps of Engineers. Atchafalaya Basin Project, Brochure, http://www.mvn.usace.army.mil/Portals/56/docs/PAO/Brochures/AtchafalayaBasinProject.PDF (accessed 12 Oct. 2018)

[USDA-NRCS] United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. US Department of Agriculture Handbook, 296.

[USDA, SCS] USDA, Soil Conservation Service. 1968. Soil Survey Interpretations for Woodland in the Southern Mississippi Valley Alluvium Area of LA MS AR TN MO and KY, Progress Report.

[USDA-NRCS] United States Department of Agriculture, Natural Resources Conservation Service. 2022. Land Resource Regions and Major Land Resource Areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture, Agriculture Handbook 296.

Contributors

D. Charles Stemmans II
R. Stout Evans
Marc Bordelon

Approval

Charles Stemmans, 6/10/2025

Acknowledgments

We would like to express our appreciation to the MLRA 131A Technical Team for their assistance and input in the development of this document. With special recognition of Tom Foti, Arkansas Natural Heritage Program and Henry Langston (retired), Arkansas Dept. of Transportation for their time, travel and knowledge assisting members of the team with field reconnaissance of several sites and assistance in verifying ecological factors.

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	08/29/2026
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 F131AY405LA

Tensas Basin - Somewhat Poorly Drained Bottomland Hardwoods

Last updated: 6/10/2025 Accessed: 08/29/2026

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General information

MLRA notes

LRU notes

Classification relationships

Ecological site concept

Associated sites

Similar sites

Figure 1. 131AY405 ES Extent Map

Table 2. Dominant plant species

Natural Resources
Conservation Service

Last updated: 6/10/2025
Accessed: 08/29/2026