LOCATION HARKEY NM+TXEstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, calcareous, thermic Typic Torrifluvents
TYPICAL PEDON: Harkey very fine sandy loam, cultivated. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 9 inches; pale brown (10YR 6/3) very fine sandy loam, brown (10YR 4/3) moist; weak, fine subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common very fine roots; common very fine pores; violently effervescent, calcium carbonate equivalent 10 percent; slightly alkaline (pH 7.8); abrupt smooth boundary. (4 to 12 inches thick)
Ck1--9 to 28 inches; light brown (7.5YR 6/4) very fine sandy loam, brown (7.5YR 4/4) moist; weak, fine subangular blocky structure and massive; hard, very friable, nonsticky and nonplastic; common medium and fine roots; common very fine pores; violently effervescent, calcium carbonate as few fine filaments and nodules, calcium carbonate equivalent 12 percent; slightly alkaline (pH 7.8); gradual wavy boundary. (8 to 24 inches thick)
Ck2--28 to 70 inches; light brown (7.5YR 6/4) loam, brown (7.5YR 4/4) moist; massive; hard, friable, slightly sticky and slightly plastic; few medium and fine roots; common very fine pores; strongly effervescent, calcium carbonate as few fine filaments and nodules, calcium carbonate equivalent 12 percent; moderately alkaline (pH 8.0).
TYPE LOCATION: Eddy County, New Mexico; 400 feet north and 500 feet east of the southwest corner section 29, T. 22 S., R. 28 E.: 104 degrees, 06 minutes, 26 seconds - west longitude; 32 degrees, 22 minutes, 00 seconds - north latitude.
RANGE IN CHARACTERISTICS:
Soil moisture - Intermittently moist in the soil moisture control section during July-August and December-January. Driest during May and June. Typic aridic soil moisture regime.
Soil Temperature: 60 to 63 degrees F.
Soil depth: greater than 60 inches.
Electrical Conductivity: 1 to 16 millimhos/cm.
Seasonal Water Table: 4 to 6 feet in depth. Some areas of Harkey are slightly saline or moderately saline or are slightly alkali or moderately alkali.
A Horizon
Hue: 10YR and 7.5YR
Value: 4 through 6 dry, 2 through 4 moist
Chroma: 3 or 4
Textures: sandy loam, clay loam, silty clay loam, silt loam, loam and very fine sandy loam.
C Horizon
Hue: 10YR and 7.5YR
Value: 4 through 6 dry, 2 through 4 moist
Chroma: 3 or 4
Texture: Silt loam, loam and very fine sandy loam.
COMPETING SERIES: This is the St. George (UT) series. St. George soils have hue mainly of 5YR or 2.5YR and have 8 to 30 percent gypsum crystals, by volume.
GEOGRAPHIC SETTING: The Harkey soils are on floodplains and stream terraces with slopes of 0 to 3 percent. They formed in calcareous mixed alluvial sediments derived from sedimentary material. Elevations range from 2,500 to 4,500 feet. Small amounts of gypsiferous material are present. The average annual temperature ranges from 60 to 64 degrees F. The average annual precipitation ranges from 8 to 12 inches; The PE index is about 13. The frost-free season is 180 to 220 days in New Mexico and as long as 240 days in Texas.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Arno, Marcmill, Pima, and Reakor. Arno soils have more than 35 percent clay on stream terraces. Marcmill soils have coarse-loamy textural control section on higher stream terraces. Pima soils have a mollic epipedon on flood plains. Reakor soils have a fine-silty moisture control section on plains.
DRAINAGE AND PERMEABILITY: well drained; slow runoff; moderate permeability.
USE AND VEGETATION: Used mainly for irrigated crops such as cotton, grain sorghums, small grains, and alfalfa. Native vegetation is mainly giant sacaton, alkali sacaton, black grama, tobosa and creosotebush.
DISTRIBUTION AND EXTENT: The Rio Grande and Pecos River Valleys in southeastern New Mexico and western Texas. The series is moderately extensive. This soil occurs in LRR-D, MLRA 42.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Carlsbad Irrigated Area, Eddy County, New Mexico, 1969.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 9 inches (Ap horizon).
Entic feature - lack of diagnostic horizons
Classified according to Soil Taxonomy Second Edition, 1999.
When the competing series section was updated in September 2001, questions were raised about the description and/or the classification of this series. It was suggested that this soil should classify in the great group of Haplocambids or Haplocalcids. A field study of the type location is recommended to resolve the questions.
ADDITIONAL DATA: This description is from a pit near the sampling site for Pedon No. S57NM-8-20 which is now within a cemetery. The physical and chemical properties of Pedon No. S57NM-8-5-(1 to 6) more nearly represent the central concept of the series.