LOCATION GRANDMORE OK+TXEstablished Series
The Grandmore series consists of very deep, moderately well drained, moderately slowly permeable soils. These soils formed in loamy alluvium of Pleistocene age. These nearly level to very gently sloping soils are on stream terraces in the Central Rolling Red Plains (MLRA 78). Slope ranges from 0 to 3 percent. Mean annual temperature is about 62 degrees F., and mean annual precipitation is about 25 inches.
TAXONOMIC CLASS: Fine-loamy, mixed, active, thermic Typic Haplustalfs
TYPICAL PEDON: Grandmore loamy fine sand--on a 2 percent slope in a cultivated field. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 10 inches; brown (7.5YR 5/4) loamy fine sand, brown (7.5YR 4/4) moist; weak medium granular structure; soft, very friable; common very fine and fine roots; neutral; abrupt smooth boundary. (5 to 19 inches thick)
Bt1--10 to 23 inches; reddish brown (5YR 5/4) sandy clay loam, reddish brown (5YR 4/4) moist; weak medium prismatic structure parting to moderate fine and medium subangular blocky; hard, firm; common very fine and fine roots; common distinct clay films on surfaces of peds and in pores; slightly alkaline; gradual smooth boundary.
Bt2--23 to 40 inches; yellowish red (5YR 5/6) sandy clay loam, yellowish red (5YR 4/6) moist; weak medium prismatic structure parting to moderate fine and medium subangular blocky; hard, firm; few very fine and fine roots; common distinct clay films on surfaces of peds and in pores; slightly alkaline; gradual smooth boundary.
Bt3--40 to 52 inches; reddish yellow (5YR 6/8) sandy clay loam, yellowish red (5YR 5/6) moist; weak coarse prismatic structure parting to weak medium and coarse subangular blocky; hard, friable; few very fine and fine roots; few faint clay films on surfaces of peds and in pores and common clay bridging between sand grains; few medium prominent light gray (10YR 7/2) and few medium distinct reddish brown (5YR 4/4) iron depletions; slightly alkaline; clear smooth boundary. (combined thickness of the Bt horizon is 10 to 45 inches thick)
2Btb--52 to 80 inches; reddish brown (5YR 5/4) clay loam, reddish brown (5YR 4/4) moist; moderate medium prismatic structure parting to moderate medium and coarse subangular blocky; very hard, very firm; few very fine and fine roots; 35 percent clay; many prominent clay films on surfaces of peds and in pores; common fine and medium masses of iron-manganese; 1 percent rounded quartzite gravel; common medium and coarse prominent light gray (10YR 7/1) iron depletions; common medium prominent yellowish brown (10YR 5/6), common medium and coarse distinct light reddish brown (5YR 6/4) and common medium and coarse faint yellowish red (5YR 5/6) moist iron concentrations; slightly alkaline. (11 to 50 inches thick)
TYPE LOCATION: Harmon County, Oklahoma; from the intersection of U.S. Highway 62 and OK State Highway 30 in Hollis; about 9 miles north on Highway 30; about 4.25 miles west on county road; about 1700 feet north in cropland at an elevation of 1,925 feet. (1680 feet north and 1300 feet west of the southeast corner of sec. 13, T. 4 N., R. 27 W.); (Latitude: 34 degrees, 49 minutes, 01.25 seconds North; Longitude: 99 degrees, 59 minutes, 12 seconds West) USGS McKnight, OK topographic quadrangle; North American Datum 1927.
RANGE IN CHARACTERISTICS:
Particle-size control section (weighted average)
Clay content: 18 to 35 percent
CEC/clay ratio: 0.4 to 0.6
Thickness of the solum: 60 to more than 80 inches
Depth to a discontinuity (with an increase in clay content): 30 to 60 inches
Depth to episaturation: 40 to 60 inches
A horizon
Hue: 5YR, 7.5YR, or 10YR
Value: 5 or 6 (4 or 5 moist)
Chroma: 2 to 4
Texture: loamy sand, loamy fine sand, or fine sandy loam
Reaction: slightly acid to moderately alkaline (6.1 - 8.4)
Bt horizon
Hue: 5YR or 7.5YR
Value: 4 to 6 (3 to 5 moist)
Chroma: 2 to 6
Texture: loam, sandy clay loam or fine sandy loam
Clay content: 15 to 30 percent
Redox features: Some pedons have few or common, fine or medium iron depletions or concentrations in shades of gray, brown, red, or yellow in the lower part.
Iron-manganese accumulations: none to common, fine or medium, masses or concretions
Reaction: neutral to moderately alkaline (6.6 - 8.4)
BC horizon (where present)
Have color, texture, and reaction similar to the Bt horizon
2Btb horizon
Hue: 5YR, 7.5YR, or 10YR
Value: 4 to 7 (3 to 6 moist)
Chroma: 1 to 4
Texture: clay loam or clay
Clay content: 30 to 45 percent
Redox features: Most pedons have few or common, fine or medium iron depletions or concentrations in shades of gray, brown, red, or yellow.
Iron-manganese accumulations: none to common, fine or medium, masses or concretions
Effervescence: noneffervescent to strongly effervescent
Calcium carbonate equivalent: 0 to 10 percent
Visible calcium carbonate (where present): few to common, fine or medium, masses or concretions
Reaction: slightly alkaline or moderately alkaline (7.4 - 8.4)
2BCb horizon (where present)
Hue: 5YR, 7.5YR, or 10YR
Value: 5 to 7 (4 to 6 moist)
Chroma: 1 to 4
Texture: clay, clay loam, sandy clay loam, fine sandy loam or loamy fine sand
Clay content: 10 to 45 percent
Redox features: Most pedons have few or common, fine or medium iron depletions or concentrations in shades of gray, brown, red, or yellow.
Iron-manganese accumulations: none to common, fine or medium, masses or concretions
Effervescence: noneffervescent to strongly effervescent
Calcium carbonate equivalent: 0 to 15 percent
Visible calcium carbonate (where present): few to common, fine or medium, masses or concretions
Reaction: moderately alkaline (7.9 - 8.4)
COMPETING SERIES: These are the
Arnett,
Cobb,
Decobb,
Grandfield,
Honeycreek,
Hye,
Lou,
McKnight,
Menard, and
Rochelle series.
Arnett series: have 5 to 35 percent gravel content consisting mainly of rounded quartzite.
Cobb series: have a solum less than 40 inches thick to soft sandstone.
Decobb and Grandfield series: do not have a discontinuity with a clay increase in the lower part of the solum.
Honeycreek series: have schist bedrock within 60 inches of the soil surface.
Hye series: have a lithic contact with sandstone at 20 to 40 inches.
Lou series: contain 15 to 35 percent gravel in the Bt and are formed from granite grus.
McKnight series: have a solum less than 50 inches thick over soft shale or sandstone.
Menard series: have secondary lime within 30 inches and have 5 to 30 percent limestone fragments in the lower part.
Rochelle series: have strongly contrasting materials within 32 inches of the soil surface.
GEOGRAPHIC SETTING:
Parent material: Loamy over more clayey alluvium derived from Pleistocene age sediments
Landform: Nearly level to very gently sloping interdunal areas on stream terraces that are slightly convex to hummocky.
Slope: 0 to 3 percent
Mean annual temperature: 57 to 64 degrees F.
Mean annual precipitation: 22 to 32 inches
Frost-free period: 185 to 230 days
Elevation: 1,000 to 2,200 feet
Thornthwaite annual P-E indices: 32 to 44
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Devol, Grandfield, Headrick, McKnight, and Ozark series.
Devol series:
Occur on higher ridges and have a course-loamy textural control section.
Grandfield and
McKnight series: Occur on slightly higher broad convex areas.
Headrick series: Occur on slightly lower broad flat to concave areas and have a perched water table within 40 inches of the surface.
Ozark series: Occur on similar areas but have a mollic epipedon.
DRAINAGE AND PERMEABILITY: Moderately well drained. Moderately slow permeability. Runoff is low on 0 to 1 percent slopes and medium on 1 to 3
percent slopes. A perched water table is 40 to 60 inches below the surface during the months October to May of most years.
USE AND VEGETATION: Used mainly as cropland. Wheat, grain sorghum, cotton, alfalfa, improved bermudagrass, and weeping lovegrass are the principal
crops. Native vegetation is mid and tall grasses.
DISTRIBUTION AND EXTENT: Central Rolling Red Plains of western Oklahoma and Texas; LRR H; MLRA 78; Moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Harmon County, Oklahoma, 1982
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle size control section: 10 to 30 inches (Bt1 & Bt2 horizons).
Ochric epipedon: 0 to 10 inches (Ap horizon).
Argillic horizon: 10 to 80 inches (Bt & 2Btb horizons).
Episaturation (perched water table): Zone of saturation at 40 to 80 inches during some part of the year (Bt3 & 2Btb horizons).
Lithologic discontinuity: At the upper boundary of the 2Btb horizon.
The assignment of the cation-exchange activity class is inferred by laboratory data from similar associated soils from Jackson County, Oklahoma.
Range Site: Loamy Sand Prairie 078CY105TX
ADDITIONAL DATA: none
TAXONOMIC VERSION: Soil Taxonomy, Second Edition, 1999.