LOCATION REEVES NM+TXEstablished Series
TAXONOMIC CLASS: Fine-loamy, gypsic, thermic Ustic Calcigypsids
TYPICAL PEDON: Reeves loam - rangeland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 3 inches; brown (10YR 5/3) loam, brown (10YR 4/3) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; strongly effervescent; moderately alkaline; abrupt smooth boundary.
A2--3 to 7 inches; light brown (7.5YR 6/4) loam, brown (7.5YR 4/4) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; common worm casts; strongly effervescent; moderately alkaline; clear smooth boundary. (the combined thickness of the A1 and A2 horizon is 2 to 15 inches)
Bk1--7 to 15 inches; light brown (7.5YR 6/4) clay loam, brown (7.5YR 5/4) moist; moderate fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; strongly effervescent; common fine calcium carbonate accumulations; moderately alkaline; clear smooth boundary. (7 to 12 inches thick)
Bk2--15 to 22 inches; light brown (7.5YR 6/4) clay loam, brown (7.5YR 5/4) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine and very fine roots; violently effervescent; few fine calcium carbonate accumulations; moderately alkaline; clear smooth boundary. (0 to 10 inches thick)
Bk3--22 to 31 inches; pink (7.5YR 8/4) clay loam, pink (7.5YR 7/4) moist; massive; slightly hard, very friable, sticky and plastic; few very fine roots; violently effervescent; few fine calcium carbonate accumulations; 1 percent gypsum; moderately alkaline; abrupt wavy boundary. (0 to 10 inches thick)
By1--31 to 40 inches; pinkish white (7.5YR 8/2) loam, pink (7.5YR 7/4) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; violently effervescent; 52 percent gypsum; moderately alkaline; clear wavy boundary. (6 to 36 inches thick)
By2--40 to 64 inches; pink (7.5YR 8/4) clay loam, light brown (7.5YR 6/4) moist; massive; slightly hard, very friable, sticky and plastic; violently effervescent; 22 percent gypsum; moderately alkaline; clear smooth boundary. (0 to 30 inches thick)
Bky--64 to 79 inches; reddish brown (5YR 5/4) clay loam, reddish brown (5YR 5/4) moist; massive; hard, friable, sticky, plastic; common gypsum mottles and crystals; 20 to 30 percent carbonate nodules; violently effervescent; moderate alkaline.
TYPE LOCATION: Chaves County, New Mexico; about 8 miles southwest of Roswell; 400 feet east and 293 feet south of the northwest corner of the northeast quarter, sec. 11, T. 12 S., R. 25 E.; lat. 35 degrees 17 minutes 55 seconds N., long. 104 degrees 25 minutes 18 seconds W.
RANGE IN CHARACTERISTICS:
Soil Moisture: Intermittently moist in some part of the soil moisture control section June through September. Ustic aridic moisture regime
Soil temperature: 59 to 66 degrees F.
Depth to gypsic horizon: 20 to 40 inches.
Gypsum content: 40 to 80 percent.
Reaction: Moderately to strongly alkaline.
A horizon: Hue: 7.5YR or 10YR
Value: 4 to 7, 3 to 6 moist
Chroma: 2 to 4
Bk or Bw horizon when present: Hue: 5YR through 10YR
Value: 5 to 8 dry, 4 to 7 moist
Chroma: 3 to 5
Texture: clay loam, silt loam or loam with 18 to 30 percent clay on a weighted average
Calcium carbonate equivalent: 15 to 25 percent on a weighted average
By horizon: Gypsiferous material ranges from slightly hard to strongly cemented.
Colors are lithochromic.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: These soils are on basin floors, plateaus and hillslopes at elevations of 2,500 to 5,300 feet. Slopes are dominantly 0 to 3 percent, but they range up to 9 percent. The parent material is calcareous impure gypsum beds. The climate is arid to semiarid with average rainfall of 10 to 15 inches. The driest period occurs between late October and May. The average annual temperature is 58 to 64 degrees F. The frost free period ranges from 180 to 230 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Atoka, Berino, Reakor, Simona, and Upton soils. Atoka, Simona and Upton soils have petrocalcic horizons. Berino soils have argillic horizons. Reakor soils lack gypsic mineralogy.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: Grazing and irrigated cropland. Crops are mostly cotton, alfalfa, sorghum, and small grains. Vegetation is mainly burrograss, tobosa, alkali sacaton, blue grama, threeawn, fourwing saltbush, and snakeweed.
DISTRIBUTION AND EXTENT: Southeastern New Mexico and western Texas. The series is of moderate extent. MLRAs 42, 70B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Reeves County Texas, 1922.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: The zone from 0 to 7 inches (A horizons).
Calcic horizon: The zone from 22 to 31 inches (Bk3 horizon).
Gypsic horizon: The zone from 31 to 79 inches (By horizons).
Calcic subgroup: The percentage of gypsum in the gypsic horizon times the thickness in cm is less than 3000.
The classification was changed in 1992 from Typic Gypsiorthids to Ustic Calcigypsids. Field study and additional data indicates that both "Ustic" and "Calcic" were mapped together in the past, but that more acres fit the "Calcic" subgroup.
ADDITIONAL DATA: NSSL characterization data; Lab No. 70L364-70L371 and 70L372-70L376