
Natural Resources
Conservation Service
Ecological site F135AY150AL
Deep Well to Moderately Well Drained Clay Acid Broad Flats
Last updated: 5/29/2025
Accessed: 07/17/2025
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): 135A–Alabama and Mississippi Blackland Prairie
This MLRA has two narrow (less than 40 miles wide), long, arching bands known as the Blackland Prairie and the Jackson Prairie, which are characterized by clayey, soils with a high shrink-swell potential. Several major drainageways bisect this region on their way to larger tributaries. Very little native prairie vegetation remains due to agriculture and forestry activities.
This area is in eastern Mississippi (57 percent) and central and western Alabama (43 percent). It makes up about 10,165 square miles (26,328 square kilometers). Most of this region is surrounded by the distinctly different MLRA 133C, which has sandy soils and stratified, coastal sediment mineralogy. A very small section of MLRA 135A has a diffuse boundary with MLRA 134 that occurs as a loess cap that gradually thins from west to east. (USDA, NRCS, 2022)
LRU notes
This ecological site can be seen in the Blackland Prairie, Jackson Prairie, and the Interior Flatwoods of MLRA 135A.
Blackland Prairie: This physiographic region is a long crescent shaped land use area that starts in northeastern Mississippi and ends in central Alabama. The Blackland Prairie soils are formed from mostly calcareous coastal plains. These soils occur on low lying, flat, broad landscapes; they are mostly alkaline, heavy clays, with some weathered acid areas. The Blackland Prairie is interspersed native prairie and hardwood forests; this area is 90% cultivated.
The Jackson Prairie: This physiographic region consists of a narrow band of soils that occurs in central Mississippi. These soils are gently sloping and formed from a heavy clay parent material. The Jackson Prairie is mostly acidic and weathered. This region is mostly a mixed conifer forest but does have some local pasture and cultivation.
The Interior Flatwoods: This physiographic region consists of a narrow band, of soils which were formed out of an acid gray clay. This band of similar soils is situated directly west of the Blackland Prairie. These acid and clayey soils are flat, low lying, mostly saturated, hardwood forests with some areas in heavy cultivation.
Classification relationships
This area is in the East Gulf Coastal Plain section of the Coastal Plain province of the Atlantic Plain. The northern part of the area is a slightly elevated, hilly plain. The separate southwestern part is locally known as the Jackson Prairie portion of the East Gulf Coastal Plain section in Mississippi. (USDA, NRCS, 2022)
National Vegetation Classification System Vegetation Association (NatureServe, 2010):
The reference state for this system is comparable to Quercus stellata - Quercus marilandica - Carya (tomentosa, pallida) Woodland (CEGL003952). Additionally, Pinus echinata - Quercus stellata - (Quercus marilandica) Forest is highly represented (CEGL004053).
Ecological site concept
These sites are found on the uplands and slopes in the transition area between MLRA 135A (Blackland Prairie) and 133C (Gulf Coastal Plains). These sites have soils that are deep, well to moderately well drained, acidic, and clayey. Historically these sites are a mixture of hardwood and pine stands interspaced by grassy patches. Today, these sites are used for cotton, corn, and soybeans. Common trees in wooded areas include loblolly pine, shortleaf pine, southern red oak, post oak, sweetgum, and hickory.
Associated sites
R135AY110MS |
Shallow to Moderately Deep Well Drained Silty Clay to Clay Alkaline Broad Flats These sites are in similar geomorphic positions with more dissected and steeper landscapes and shallower soils than F135AY150AL |
---|---|
R135AY130MS |
Deep Moderately Well to Well Drained Clay Alkaline Broad Flats These sites are found in similar geomorphic positions with more calcareous soils than F135AY150AL |
R135AY140MS |
Deep Somewhat Poorly Drained Clay Alkaline Broad Flats These sites are traditionally lower on the landscape than F135AY150AL |
F135AY160MS |
Deep Somewhat Poorly Drained Clay Acid Broad Flats These sites are found in similar geomorphic positions the primary difference being a poorer drainage class than F135AY150AL |
F135AY170AL |
Deep Well Drained Fine Loamy Acid Broad Flats These sites have similar geomorphic positions and have a loamier texture than F135AY150AL |
F135AY220MS |
Deep Poorly Drained Clay Nonacid Floodplains These sites are found in the floodplains below F135AY150AL |
F135AY230MS |
Deep Somewhat Poorly Drained To Moderately Well Drained Clay Alkaline Floodplains These sites are found in the floodplains below F135AY150AL |
F135AY250MS |
Deep Moderately Well Drained Fine Loamy Acid Floodplains These sites are found in the floodplains below F135AY150AL |
F135AY330MS |
Deep Moderately Well Drained Fine Loamy Acid Flatwoods Uplands These sites are found lower on the landscape with gentler slopes than F135AY150AL |
F135AY350AL |
Deep Moderately Well Drained Clay Acid Flatwoods Slopes These sites are found lower on the landscape with gentler slopes than F135AY150AL |
F135AY370MS |
Deep Somewhat Poorly Drained Fine Loamy Acid Flatwoods Stream Terraces These sites are found on the stream terraces below F135AY150AL |
F135AY390MS |
Deep Somewhat Poorly Drained Fine Silty Acid Flatwood Floodplains These sites are found in the floodplains below F135AY150AL |
Similar sites
R135AY130MS |
Deep Moderately Well to Well Drained Clay Alkaline Broad Flats These sites are alkaline as apposed to acid like F135AY150AL |
---|---|
F135AY160MS |
Deep Somewhat Poorly Drained Clay Acid Broad Flats These sites have a poorer drainage class than F135AY150AL |
F135AY170AL |
Deep Well Drained Fine Loamy Acid Broad Flats These sites have a loamier texture than F135AY150AL |
F135AY180MS |
Deep Somewhat Poorly Drained To Moderately Well Drained Fine Silty Acid Broad Flats These sites have a siltier soil texture than F135AY150AL |
F135AY310AL |
Deep Moderately Well Drained Clay Acid Flatwoods Uplands These sites have very similar soils but are located in the flatwoods as opposed to the Blackland Prairie like F135AY150AL |
F135AY330MS |
Deep Moderately Well Drained Fine Loamy Acid Flatwoods Uplands These sites are located in the flatwoods and have a loamier soil textures as compared to F135AY150AL |
F135AY350AL |
Deep Moderately Well Drained Clay Acid Flatwoods Slopes These sites are located in the flatwoods and are found on greater slopes as compared to F135AY150AL |
Table 1. Dominant plant species
Tree |
(1) Quercus stellata |
---|---|
Shrub |
(1) Quercus alba |
Herbaceous |
(1) Smilax glauca |
Click on box and path labels to scroll to the respective text.
Ecosystem states
States 2, 8, 3 and 7 (additional transitions)
States 3, 8 and 4 (additional transitions)
T1-2 | - | No fire disturbance |
---|---|---|
T1-3 | - | Intense disturbance |
T2-3 | - | Intense disturbance |
T2-8 | - | Manage for fire dependent forest |
T3-2 | - | Prevent fire and other disturbances |
T3-4 | - | Plant and manage for desired silviculture community |
T3-5 | - | Manage for pasture |
T3-6 | - | Manage for crops |
T3-7 | - | Manage for aquaculture |
T3-8 | - | Manage for fire dependent forest |
T4-2 | - | Leave unmanaged |
T4-3 | - | Clear the trees, ensure the desired area has a wetland determination |
T4-5 | - | Mange for pasture |
T4-6 | - | Mange for crops |
T4-8 | - | Manage for fire dependent forest |
T5-3 | - | Any significant disturbance |
T5-4 | - | Manage for silviculture community |
T5-6 | - | Manage for crops |
T5-7 | - | Manage for aquaculture |
T5-8 | - | Manage for fire dependent forest |
T6-3 | - | Any significant disturbance can cause this shift |
T6-4 | - | Manage for silviculture |
T6-5 | - | Mange for pasture |
T6-7 | - | Manage for aquaculture |
T6-8 | - | Manage for fire dependent forest |
T7-3 | - | Fill ponds with soil, the grassland will be the first state in succession if management is not applied |
T8-2 | - | Prevent disturbance |
T8-3 | - | Intense disturbance |
T8-4 | - | Manage for desired silviculture community |
T8-5 | - | Manage for desired tree species |
T8-6 | - | Manage for desired crops |
T8-7 | - | Manage for aquaculture |
State 1 submodel, plant communities
State 2 submodel, plant communities
2.1A | - | Increased soil moisture |
---|---|---|
2.2A | - | Decreased soil moisture |