LOCATION ANDRY LAEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, thermic Typic Argiaquolls
TYPICAL PEDON: Andry peat--marsh land--wildlife habitat.
(Colors are for moist soil unless otherwise
stated.)
021--12 to 6 inches; very dark grayish brown (10YR 3/2) hemic material; about 50 percent fiber, about 30 percent rubbed;
massive; nonsticky; many live roots; neutral; gradual wavy
boundary. (4 to 8 inches thick)
022--6 to 0 inches; very dark grayish brown (10YR 3/2) hemic material; about 40 percent fiber, about 20 percent rubbed;
massive; nonsticky; mineral content about 50 percent; slightly
acid; gradual smooth boundary. (4 to 8 inches thick)
A11--0 to 6 inches; black (10YR 2/1) silt loam; weak granular structure; nonsticky; many medium roots; about 12 percent fiber
after rubbing; neutral; gradual smooth boundary. (4 to 8 inches thick)
A12--6 to 13 inches; very dark gray (10YR 3/1) silt loam;
dark gray (N 4/0) when wet and first exposed to air; weak medium subangular blocky structure; very plastic and sticky; common
medium and fine roots; neutral; gradual smooth boundary. (5 to 10 inches thick)
B21tg--13 to 26 inches; very dark gray (10YR 3/1) silty clay loam; dark gray (N 4/0) when wet and first exposed to air; many medium and coarse prominent light olive brown (2.5YR 4/4) mottles; weak medium subangular blocky structure; plastic and sticky; few
fine roots; few soft Fe-Mn accumulations; few thin patchy clay
films; neutral; gradual smooth boundary. (5 to 15 inches thick)
B22tg--26 to 33 inches; greenish gray (5GY 5/1) silty clay
loam; many medium and coarse distinct olive (5Y 5/3) mottles; weak medium and coarse subangular blocky structure; plastic and sticky; few fine roots; few Fe-Mn concretions; thin patchy clay films; neutral; gradual smooth boundary. (5 to 15 inches thick)
B3g--33 to 60 inches; greenish gray (5GY 6/1) and gray (N
6/0) silty clay loam; many coarse distinct olive (5Y 5/3) mottles; weak very coarse prismatic structure; plastic; neutral.
TYPE LOCATION: Iberia Parish, Louisiana; 3 3/4 miles
south-southeast of Delcambre; 50 yards west of canal; NE1/4SW1/4
sec. 21, T. 13 S., R. 5 E.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 40 to 65 inches. Soil salinity ranges from slight to high in the 02
horizon, and is moderate to high in the mineral horizons. Exchangeable sodium percentage ranges from 8 to 20 percent or
more, and increases with increasing depth.
The 02 horizon is very dark grayish brown (10YR 3/2), dark grayish brown (10YR 4/2; 2.5Y 4/2), black (N 2/0; 10YR 2/1), dark gray
(10YR 4/1), very dark brown (10YR 2/2; 7.5YR 3/2), or very dark
gray (10YR 3/1). It is hemic or sapric material and typically has
a mat of live roots in the upper part. The 02 horizon is medium
acid through mildly alkaline but becomes extremely acid or very strongly acid when drained. The colors of the mineral horizons
are about one color value higher when wet and first exposed to air than when moist.
The A horizon is black (10YR 2/1; N 2/0; 5Y 2/1), very dark gray
(5YR 3/1; N 3/0; 10YR 3/1), or very dark grayish brown (10YR 3/2) mucky silt loam, mucky silty clay loam, silt loam, or silty clay loam. It is medium acid through mildly alkaline but becomes
strongly acid or very strongly acid after drainage.
The Bt horizon is gray (10YR 5/1, 6/1; N 6/0; 5Y 5/1, 6/1), dark
gray (10YR 4/1; 5Y 4/1; N 4/0), very dark gray (10YR 3/1), or greenish gray (5GY 5/1, 6/1). Mottles are in shades of brown or olive. The Bt horizon is silt loam or silty clay loam. It is neutral through moderately alkaline. Some pedons have 5 to 10 percent calcium carbonate in subhorizons of the B or C horizons.
COMPETING SERIES: These are the
Jeanerette,
Morey, and Urich
series in the same family and
Addicks,
Carwile,
Chobee,
Copeland,
Delcomb,
Harris,
Muldrow,
Rio, and
Stono series. All of the competing soils except the Delcomb series lack histic epipedons. Additionally, Addicks, Chobee, Copeland, and Stono soils have fine loamy control sections. Carwile, Harris, Muldrow, and Rio soils
have fine textured control sections. Delcomb soils have organic surface layers that are 16 to 50 inches thick. Morey soils have
15 to 35 percent sand that is dominantly very-fine.
GEOGRAPHIC SETTING: Andry soils are at low elevations on the brackish coastal marshes that are subject to frequent flooding by fresh and brackish water. Slope gradients are less than 0.25 percent. The soil formed in 8 to 15 inches of organic material derived mainly from herbaceous plant remains over submerged soils formed in prairie age loess-like deposits. The climate is humid-subtropical. The average annual temperature near the type location is about 68 degrees F., and the average annual
precipitation is about 60 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Delcomb, Iberia, and Jeanerette series. Andry soils are considered to be formed in submerged Jeanerette soils.
DRAINAGE AND PERMEABILITY: Very poorly drained; very slow surface runoff; moderately slow permeability. Flooded most of the time
with up to 4 inches of slightly saline water unless drained.
USE AND VEGETATION: These soils are used for range wildlife
habitat. The vegetation is water tolerant herbaceous plants including marshhay cordgrass, big cordgrass, switchgrass, common reed, longtom, olney bulrush, and cattail.
DISTRIBUTION AND EXTENT: The coastal areas in Louisiana and
possibly Mississippi and Texas. Series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Iberia Parish, Louisiana; 1973.
REMARKS: Andry soils formerly were included in the Harris series
and classified as Bog soils. The classification of this soil is provisional. The argillic horizon of the Andry soils is
considered to have formed before the soils were submerged; the
hictic horizons and increase in sodium formed after submergence. After further study a new subgroup will be proposed for soils of
this character.