LOCATION TALCO TXEstablished Series
TAXONOMIC CLASS: Fine-silty, siliceous, active, thermic Aeric Glossaqualfs
TYPICAL PEDON: Talco silt loam--pasture.
(Colors are for moist soil unless otherwise stated.)
A--0 to 3 inches; grayish brown (10YR 5/2) silt loam; weak very fine and fine subangular blocky structure; loose, friable; many fine and medium roots; slightly acid; clear smooth boundary. (3 to 10 inches thick)
E/B--3 to 8 inches; mottled pale brown (10YR 6/3) (E), yellowish brown (10YR 5/4) (B), light brownish gray (10YR 6/2) (E) silt loam; weak fine and medium subangular blocky structure; slightly hard, friable; many fine roots; strongly acid; clear smooth boundary. (4 to 10 inches thick)
Bt/E--8 to 13 inches; brownish yellow (10YR 6/6) silt loam; many coarse distinct light brownish gray (10YR 6/2) mottles; moderate fine and medium subangular blocky structure; slightly hard, friable; common fine and medium roots; many thin clay films on faces of peds; 5 to 10 percent by volume light gray (10YR 7/2) streaks of silt and uncoated sand (E) 3-8 mm wide and 1-2.5 cm long; very strongly acid; gradual smooth boundary. (0 to 10 inches thick)
Btg/E1--13 to 22 inches; light brownish gray (10YR 6/2) silt loam; many medium distinct brownish yellow (10YR 6/8) and yellowish brown (10YR 5/8) mottles; weak fine and medium subangular blocky structure; hard, friable; few fine and medium roots; many thin clay films on faces of peds; 10 to 15 percent by volume light gray (10YR 7/2) streaks of silt and uncoated sand (E) 3-8 mm wide and 2-3 cm long with few pockets less than 2 cm across; very strongly acid; gradual smooth boundary. (7 to 17 inches thick)
Btg/E2--22 to 35 inches; light brownish gray (10YR 6/2) silt loam; common medium distinct yellowish brown (10YR 5/6) and many fine distinct light yellowish brown (10YR 6/4) and brownish yellow (10YR 6/6) mottles ; fine and medium blocky structure; hard, firm; few fine and medium roots; thin clay films on surface of peds; 15 to 20 percent by volume light gray (10YR 7/2) streaks of silt and uncoated sand 3-10 mm wide and 3-5 cm long, few pockets less than 2 cm across; very strongly acid; clear smooth boundary. (0 to 16 inches thick)
Btg1--35 to 49 inches; gray (10YR 5/1) silty clay; common fine distinct brown and few fine distinct brownish yellow mottles; weak coarse prismatic parting to moderate fine and subangular blocky structure; hard, very firm; few fine and medium roots; thin clay films on surface of peds; faces of some peds are stained with iron-oxide; few dark concretions 2 to 7 mm in diameter; common vertical streaks of gray (10YR 4/1); few pockets of pale brown (10YR 6/3) silty clay loam about 2 to 6 cm across; few streaks less than 5 mm wide of light gray (10YR 7/2) silt and uncoated sand grains on surface of some peds; very strongly acid; gradual irregular boundary. (10 to 30 inches thick)
Btg2--49 to 66 inches; grayish brown (10YR 5/2) clay loam; few medium prominent red (2.5YR 4/8) and common fine distinct brownish yellow mottles; weak coarse prismatic parting to moderate fine and medium subangular blocky structure; hard, firm; few fine and medium roots; thin clay films on surface of peds; faces of some peds stained with iron-oxide; few dark concretions 2 to 7 mm in diameter; few pockets of pale brown (10YR 6/3) silty clay loam about 2 to 6 cm across; very strongly acid; gradual wavy boundary. (10 to 24 inches thick)
Btg3--66 to 80 inches; light brownish gray (10YR 6/2) clay loam; many medium distinct brownish yellow (10YR 6/6) mottles; weak coarse prismatic parting to weak fine and medium subangular blocky structure; hard, firm; few fine and medium roots; thin clay films on surface of some peds; few dark concretions 2 to 7 mm in diameter; very strongly acid.
TYPE LOCATION: Titus County, Texas; from junction of Farm Road 1402 and Farm Road 71 in Wilkinson, Texas; about 2.4 miles east on Farm Road 71; 100 feet north highway.
RANGE IN CHARACTERISTICS: The solum ranges from 60 to more than 80 inches thick. These alluvial sediments range from 5 to about 15 feet thick over shale of the Wilcox Geologic Formation. The average clay content of the control section ranges from 20 to 30 percent with less than 15 percent fine sand or coarser.
The A horizon has hue of 7.5YR or 10YR, value of 4 to 6, and chroma of 2 or 3. Mottles in shades of gray or brown range from none to a mottled matrix of these colors. It is silt loam or loam and reaction ranges from medium acid to neutral.
The E or E/B horizons have hue of 7.5YR or 10YR, value of 5 or 6 and chroma of 2 to 4. Many pedons are mottled in these colors. The B part is brown or yellow. Texture is silt loam or loam and reaction is very strongly acid or strongly acid.
The Bt/E or Btg/E horizons have hue of 7.5YR or 10YR, value of 5 or 6 and chroma of 1 to 6 in the B material. Btg/E horizons have chroma of 1 or 2. Mottles range from few to many in shades of brown and red. The E part has hue of 10YR, value of 6 to 8 and chroma of 1 or 2. Texture is silt loam, clay loam, or silty clay loam. Streaks and small pockets of albic materials make up 10 to 30 percent by volume of this horizon. The reaction is very strongly acid or strongly acid.
The Btg horizon has hue of 10YR or 2.5Y, value of 5 to 7, and chroma of 1 or 2. Mottles in shades of red, yellow, or brown range from few to many. The texture is silty clay, silty clay loam, clay, or clay loam. The clay content ranges from 27 to 50 percent and the reaction is very strongly acid or strongly acid.
The BCg horizon, when encountered, has hue of 10YR or 2.5Y, value of 5 to 7, and chroma of 1 or 2. Reddish, yellowish, or brownish mottles range from few to many. Texture is silt loam, silty clay loam, or loam. The reaction is very strongly acid or strongly acid.
COMPETING SERIES: These are the Bissonnet series in the same family and the similar Aldine, Alikchi, Caddo, Calhoun, Derly, Diboll, Fountain, Frost, Guyton, Mollville, Waller and Wrightsville. Bissonnet soils have A horizons greater than 20 inches thick. Aldine soils have contrasting control sections. Alikchi, Caddo, Calhoun, Derly, Fountain, Frost, Guyton, Mollville, Waller, and Wrightsville soils have chroma of 2 or less dominant to a depth of 30 inches and are poorly drained. In addition, Derly and Wrightsville soils have fine textured control sections. Diboll soils have coarse loamy control sections and a paralithic contact within 60 inches of the surface.
GEOGRAPHIC SETTING: Talco soils are on nearly level slightly depressional or mounded stream terraces or remnants there of 50 to 200 feet above present streams. They occupy the intermound position in mounded soil areas. Slopes range from 0 to 2 percent but are mainly less than 1 percent. The soil formed in Pleistocene Age loamy alluvial deposits. Mean annual precipitation is 42 to 48 inches. The average summer moisture deficit is 4 or 5 inches; but the annual moisture deficit is plus 4 or 5 inches. Mean annual temperature ranges from 62 to 66 degrees F. and the Thornthwaithe annual P-E indices ranges from 68 to 76.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Derly soils of the competing series and the Bowie, Freestone, Kullit, Nahatche, Raino, and Woodtell series. The Derly soils are in poorly drained, depressional areas subject to ponding. Bowie, Freestone, and Kullit are loamy soils on slightly higher nearby uplands. Nahatche soils are on lower elevations of flood plains. Raino soils are on associated mounds on the same surface. Woodtell soils have clayey argillic horizons and are on side slopes along drains below or on low hills slightly above Talco soils.
DRAINAGE AND PERMEABILITY: Talco soils are somewhat poorly drained. Runoff is very slow and permeability is slow. The soil has a perched water table 3 to 6 months during most years. Ponding occurs for brief periods during the winter and spring months.
USE AND VEGETATION: Mainly used for forest and pasture. Forest vegetation includes willow oak, water oak, post oak, red oak, sweetgum, black gum, elm, and loblolly pine.
DISTRIBUTION AND EXTENT: Northeast Texas and possibly Arkansas and Louisiana. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Titus County, Texas; 1984.
REMARKS: Diagnostic horizons and features recognized in this pedon are: Argillic horizon from 8 to 80 inches, aquic moisture regime, Glossic properties in upper part of argillic horizon. Talco soils were formerly included in the Derly or Wrightsville series. This soil is classified Glossaqualfs based on volume of glossic materials and not on size of glossic penetrations or tongues.
ADDITIONAL DATA: Pedon No. S82TX-449-3. TAMU Lab. Nos. 1430-1437.