LOCATION NIWANA TX+LAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, siliceous, semiactive, thermic Typic Paleudults
TYPICAL PEDON: Niwana fine sandy loam, on mound,-- forest.
(Colors are for moist soil unless otherwise stated.)
A--0 to 4 inches; dark grayish brown (10YR 4/2) fine sandy loam; weak fine granular structure; soft, very friable; many fine and medium roots, common fine and medium pores; very strongly acid; clear smooth boundary. (4 to 6 inches thick)
E--4 to 25 inches; pale brown (10YR 6/3) fine sandy loam; weak fine subangular blocky structure; soft, very friable; few fine, medium and coarse roots; few fine and medium pores; 3 percent rounded ironstone nodules; very strongly acid; clear smooth boundary. (16 to 23 inches thick)
Bt/E1--25 to 40 inches; brownish yellow (10YR 6/6) loam (Bt); 15 percent of the horizon consists of very pale brown (10YR 7/4) (E); weak medium subangular blocky structure; soft, very friable; few coarse roots; few fine pores; few distinct clay films on surfaces of peds; 4 percent ironstone nodules; 3 percent fine and medium faint brownish yellow (10YR 6/8) iron concentrations with sharp boundaries; very strongly acid; gradual irregular boundary. (14 to 30 inches thick)
Bt/E2--40 to 62 inches; brownish yellow (10YR 6/8) sandy clay loam (Bt); 15 percent of the horizon consists of very pale brown (10YR 7/3) (E); moderate medium subangular blocky structure; hard, firm; few coarse roots; few fine pores; few distinct clay films on surfaces of peds; 2 percent ironstone nodules; 2 percent fine prominent red (2.5YR 5/8) iron concentrations with sharp boundaries; 5 percent fine faint brownish yellow (10YR 5/8) iron concentrations with sharp boundaries; 1 percent fine light gray (10YR 7/1) iron depletions with clear boundaries; very strongly acid; gradual irregular boundary. (11 to 24 inches thick)
Bt/E3--62 to 80 inches; brownish yellow (10YR 6/6) sandy clay loam (Bt); 15 percent of the horizon consists of very pale brown (10YR 7/3)(E); moderate medium subangular blocky structure; hard, firm; 2 percent ironstone nodules; 2 percent fine prominent red (2.5YR 5/8) iron concentrations with sharp boundaries; 5 percent fine faint brownish yellow (10YR 5/8) iron concentrations with sharp boundaries; 2 percent medium distinct light gray (10YR 7/2) iron depletions with clear boundaries; very strongly acid.
TYPE LOCATION: Jasper County, Texas; from the intersection of U. S. Highway 96 and Farm Road 82 at Kirbyville; 3.3 miles west on Farm Road 82; 0.9 mile south on county road; 2.7 miles southwest and west on forest road; 0.5 mile northeast of forest trail; 150 feet east on mound.
RANGE IN CHARACTERISTICS: Solum thickness is more than 80 inches. Base saturation ranges from 15 to 35 percent at 72 inches. Average clay content in the particle-size control section ranges from 8 to 15 percent. CEC to clay ratio ranges from 0.30 to 0.40. The combined thickness of the A and E horizon is more than 20 inches.
The A horizon has a hue of 10YR, value of 3 to 5, and chroma of 2 or 3. Texture is fine sandy loam or very fine sandy loam, fine sandy loam, or loam. Reaction is very strongly acid or strongly acid.
The E horizon has hue of 7.5YR or 10YR, value of 4 to 6, and chroma of 3 or 4. Texture is very fine sandy loam, loam, or fine sandy loam. Reaction ranges from very strongly acid or strongly acid.
The Bt part of the upper Bt/E horizon has hue of 7.5YR or 10YR, value of 5 or 6, and chroma of 6 to 8. The Bt/E horizon has texture of fine sandy loam or loam, with clay content of less than 18 percent. The E part has hue of 10YR, value of 6 or 7, and chroma of 3 or 4. The E material ranges from 15 to 25 percent. Iron concentrations in shades of yellow or brown range from 0 to 5 percent. Reaction is very strongly acid or strongly acid.
The Bt part of the lower Bt/E horizon has hue of 7.5YR or 10YR, value 5 or 6, and chroma of 6 to 8. The Bt/E horizon has texture of loam or sandy clay loam. Clay content ranges from 18 to 30 percent. The E part has hue of 10YR, value of 6 or 7, chroma of 3 or 4. The amount of E material decreases with depth. Iron concentrations in shades of brown, yellow, or red ranges from 2 to 15 percent. Iron depletions in shades of gray ranges from 0 to 3 percent. Plinthite ranges from 0 to 3 percent. Masses of brittle soil materials make up to 20 percent of the volume in some pedons. Reaction is very strongly acid or strongly acid.
COMPETING SERIES: This includes the Benndale and Dallardsville series in the same family. Similar soils include the Belrose, Butters, Dallardsville, Heidel, and McLaurin series. Belrose soils have a superactive CEC to clay class and have formed in sediments of the Deweyville Formation. Benndale soils have a A horizon less than 20 inches thick and do not have a glossic horizon. Butters soils have a bisequum pedon. Dallardsville soils are moderately well drained and have a fragipan below 40 inches. Heidel and McLaurin soils have hues of 5YR or redder. Also, McLaurin soils have a subactive CEC to clay class and are on broad ridgetops and upper hillsides of ridges.
GEOGRAPHIC SETTING: Niwana soils are on mounds on nearly level to gently sloping uplands. Slopes are 0 to 1 percent. These soils are on the flatwoods mainly east of the Trinity River. These soils are forming in loamy alluvial sediments of the Lissie Formation of early to mid Pleistocene age. Mean annual precipitation is 48 to 56 inches. Mean annual temperature is 67 to 69 degrees F. Frost free days range from 240 to 270 days. Elevation ranges from 50 to 150 feet. Thornthwaite P-E index ranges from 68 to 80.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dallardsville, Jasco, Kirbyville, Kountze, Otanya, Plank, and Waller series. Dallardsville soils are moderately well drained and on lower landscape positions. Jasco soils have a fragipan and occur in depressions. Kirbyville, Kountze, and Otanya soils have more than 5 percent plinthite, are on slightly higher landscape positions. Plank soils are Vermaqualfs and are on lower landscape positions. Waller soils are Glossaqualfs and are on lower landscape positions.
DRAINAGE AND PERMEABILITY: Niwana soils are well drained. Runoff is negligible on 0 to 1 percent slopes and very low on 1 to 3 percent slopes. Permeability is moderate.
USE AND VEGETATION: Used mainly for timber with some areas used as improved pasture. Native vegetation is loblolly and shortleaf pine with mixed hardwoods. The understory is dogwood, yaupon, wax myrtle, pinehill bluestem and other grasses. Improved pastures are mainly bermudagrass and bahiagrass.
DISTRIBUTION AND EXTENT: Western Gulf Coast Flatwoods (MLRA 152B) of southeastern Texas and possibly Louisiana. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas.
SERIES ESTABLISHED: Jasper County, Texas; 1980.
REMARKS: This soil was formerly included with Elysian and Besner series. The drainage class was changed from moderately well drained to well drained due to soil moisture monitoring on the map unit type location in Hardin County, Texas.
Diagnostic horizons and features in this pedon are:
Ochric epipedon--0 to 25 inches (A and E horizon)
Glossic horizon--25 to 80 inches (Bt/E horizons)
Argillic horizon--25 to 80 inches (Bt/E horizon)
SOIL INTERPRETATION RECORD: TX0866