LOCATION CHIRENO TXEstablished Series
TYPICAL PEDON: Chireno loam--on a smooth 1 percent slope, in pasture. (colors are for moist soil unless otherwise stated.)
A--0 to 30 cm (0 to 12 in); very dark gray (10YR 3/1) loam, very dark grayish brown (10YR 3/2) dry; moderate medium subangular blocky structure parting to moderate fine granular; slightly hard, friable; many fine and medium roots; few tubular pores; few medium worm casts; slightly acid; gradual wavy boundary. (6 to 16 inches thick)
Bt1--30 to 50 cm (12 to 20 in); very dark gray (10YR 3/1) clay loam, very dark grayish brown (10YR 3/2) dry; moderate medium subangular blocky structure parting to moderate fine subangular blocky; slightly hard, friable; many fine and common medium roots; many fine discontinuous tubular pores; common fine distinct dark yellowish brown (10YR 4/6) redox concentrations; few clay films in pores; few fine iron-manganese concretions; few medium worm casts; neutral; gradual wavy boundary.
Bt2--50 to 64 cm (20 to 25 in); very dark grayish brown (10YR 3/2) clay; moderate medium subangular blocky structure parting to moderate fine subangular blocky; hard, firm; common fine and few medium roots; common fine discontinuous tubular pores; few clay films in pores; common coarse faint dark yellowish brown (10YR 3/4) redox concentrations; few fine spots of very dark gray; common fine and very fine iron-manganese concretions; few medium worm casts; neutral; gradual wavy boundary.
Bt3--64 to 104 cm (25 to 41 in); distinctly mixed with 40 percent very dark gray (10YR 3/1), 30 percent yellowish brown (10YR 5/4) and 30 percent dark yellowish brown (10YR 4/6) clay; moderate coarse prismatic structure parting to moderate medium angular blocky; hard, firm; common fine roots; common fine discontinuous tubular pores; few clay films in pores; few thin discontinuous very dark gray (10YR 3/1) organic coats on surface of prisms; few medium masses of iron-manganese in lower part of horizon; neutral; gradual wavy boundary.
Bt4--104 to 152 cm (41 to 60 in); 60 percent dark yellowish brown (10YR 4/6), 30 percent very dark gray (10YR 3/1) and 10 percent reddish brown (2.5YR 4/4) clay loam; moderate coarse prismatic structure parting to moderate medium angular blocky; hard, firm; few fine roots; few fine discontinuous tubular pores; few clay films in pores; few thin discontinuous distinct very dark gray (10YR 3/1) organic coats on surface of prisms; common medium masses of iron-manganese; neutral; gradual wavy boundary.
Bt5--152 to 203 cm (60 to 80 in); dark yellowish brown (10YR 4/6) sandy clay loam; few fine distinct olive brown (2.5Y 4/4) masses; moderate coarse prismatic structure parting to moderate medium angular blocky; hard, firm; few fine roots; few fine discontinuous tubular pores; few clay films in pores; few thin discontinuous distinct very dark gray (10YR 3/1) organic coats on surfaces of prisms; common medium masses of iron-manganese; neutral. (combined Bt subhorizons extend to more than 80 inches)
TYPE LOCATION: Houston County, Texas; from the intersection of Texas Highway 19 and Farm Road 227 in Grapeland, 4.0 miles east on Farm Road 227; 0.7 mile south on private field road; 600 feet east in pasture. Grapeland USGS quad; Latitude, 31 degrees, 29 minutes, 23 seconds N; Longtitude, 95 degrees, 24 minutes, 23 seconds W. NAD 83.
RANGE IN CHARACTERISTICS:
Soil Moisture: An udic soil moisture regime. The soil moisture control section is not dry in any part for as long as 90 cumulative days in normal years.
Mean annual soil temperature: 19 to 21 degrees C (67 to 69 degrees F)
Depth to argillic horizon: 15 to 41 cm (6 to 16 in)
Thickness of the solum: more than 203 cm (more than 80 in)
Particle-size control section (weighted average):
Clay content: 35 to 42 percent
CEC/clay ratio: 0.60 or more
Mollic epipedon: 50 to 100 cm (20 to 40 in) thick
Iron-Manganese concretions and masses: few to common in most pedons, but mainly below a depth of 100 cm (40 in)
A horizon
Hue: 7.5YR or 10YR
Value: 2 or 3
Chroma: 1 to 3
Texture is loam or clay loam
Clay content: 15 to 30 percent
Reaction: moderately acid to neutral (5.6 to 7.3)
Upper Bt horizon
Hue: 7.5YR to 5Y
Value: 3
Chroma: 1 to 3
Texture: clay loam or clay in the upper and middle part and sandy clay loam or clay loam in the lower part
Reaction ranges: slightly acid to slightly alkaline (6.1 to 7.8)
Redox concentrations: amount-few to common, size-fine and medium, contrast-distinct, boundary-diffuse or clear, located mainly below a depth of 100 cm (40 in)
Middle Bt horizon
Hue: 7.5YR to 5Y
Value: 3 to 6
Chroma: 1 to 8
Texture: clay loam or clay
Reaction ranges: slightly acid to slightly alkaline (6.1 to 7.8)
Other features: The masses of iron-manganese in the lower part appear to indicate significant durations of saturation. The glauconitic parent materials resist reduction. This may be the reason there are no redox depletions.
Lower Bt horizon
Hue: 7.5YR to 5Y
Value: 4 to 6
Chroma: 4 to 8
Texture: sandy clay loam, clay loam or clay
Reaction ranges: slightly acid to slightly alkaline (6.1 to 7.8)
Redox concentrations: amount-few to common, size-fine and medium, contrast-distinct, boundary-diffuse or clear, located mainly below a depth of 100 cm (40 in)
Other features: The glauconitic parent materials resist reduction. This may be the reason there are no redox depletions.
COMPETING SERIES: There are no other series in this family. Similar soils are the
Alto,
Eram,
Barton, and
Percilla series.
Alto soils: do not have a mollic epipedon.
Eram and
Garton soils: have a water table within 102 cm (40 in) of the surface and are not in a pachic subgroup.
Priscilla soils: have aquic soil conditions within 50 cm (20 in) of the soil surface.
GEOGRAPHIC SETTING:
Parent material: Loamy alluvium on Pleistocene Age stream terrace
Landscape: Coastal Plain
Landform: Tread on stream terrace
Slope: 0 to 2 percent
Mean annual air temperature range: 18 to 20 degrees C (65 to 67 degrees F)
Mean annual rainfall range: 1016 to 1270 mm (40 to 50 in)
Frost-free period: 235 to 245 days
Elevation: 85 to 183 m (280 to 600 ft)
Thornthwaite P-E index: 68 to 84
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing
Alto and
Percilla series, and the
Hannahatchee,
Nacogdoches,
Trawick, and
Tuscosso series. Hannahatchee, Nacogdoches, Trawick, and Tuscosso soils: do not have a mollic epipedon.
Alto soils: are on similar but slightly higher positions.
Percilla soils: are in wet depressions.
Hannahatchee and Tuscosso soils: on lower flood plain positions.
Nacogdoches and Trawick soils: are above on hills and side slopes.
DRAINAGE AND PERMEABILITY: Chireno soils are moderately well drained and moderately slowly permeable. Runoff is very low. A water table is below a depth of 100 cm (40 in) during the cool season for brief to long periods.
USE AND VEGETATION: Used mainly for pasture with minor areas of cropland and woodland. Pastures include bahiagrass and commom and improved bermudagrass. Native trees are red oak, water oak, loblolly pine, and shortleaf pine.
DISTRIBUTION AND EXTENT: Redland belt of East Texas, MLRA 133B. The series is of minor extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Nacogdoches County, Texas; 1976.
REMARKS: These soils were included in the Alto series in Cherokee County and have had a field name of Blake.
Diagnostic Horizons and Features in this pedon are:
Mollic epiedon---0 to 64 cm (0 to 25 in) (A, Bt1, and Bt2 horizons).
Argillic horizon---30 to 203 cm (12 to 80 in) (Bt1-Bt5 subhorizons).
Redox concentrations are below a depth of 30 cm (12 in).
ADDITIONAL DATA: NSSL data sample Number S74TX-347-1, Nacogdoches, County (particle-size and mineraloghy on 2 subhorizons) and sample number S86-TX-225-006, Houston, County (complete characterization data).
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