LOCATION NAKAI UT+AZEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Typic Haplocalcids
TYPICAL PEDON: Nakai loamy fine sand--rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 5 inches; reddish yellow (7.5YR 6/6) loamy fine sand, strong brown (7.5YR 5/6) moist; weak thick platy structure parting to single grain; soft, very friable; few medium and fine roots; common medium and fine discontinuous pores; slightly calcareous; moderately alkaline (pH 8.4); clear wavy boundary. (2 to 6 inches thick)
Bw--5 to 21 inches; reddish yellow (5YR 6/6) loamy fine sand, yellowish red (5YR 5/6) moist; massive; soft, very friable; few fine roots; few medium and common fine and very fine pores; slightly calcareous; strongly alkaline (pH 8.6); clear wavy boundary. (16 to 20 inches thick)
Bk1--21 to 26 inches; reddish yellow (5YR 6/6) fine sandy loam, yellowish red (5YR 5/6) moist; massive; slightly hard, very friable, slightly plastic; few fine roots; common fine and very fine pores; strongly calcareous; strongly alkaline (pH 8.8); clear wavy boundary. (5 to 10 inches thick)
Bk2--26 to 34 inches; pinkish white (7.5YR 8/2) very fine sandy loam, pinkish gray (7.5YR 6/2) moist; massive; hard, friable, slightly plastic; few very fine roots; many very fine pores; strongly calcareous; strongly alkaline (pH 9.0); clear wavy boundary. (6 to 14 inches thick)
C--34 to 60 inches; pink (7.5YR 7/4) loamy fine sand, brown (7.5YR 5/4) moist; massive; soft, very friable, many fine interstitial pores; moderately calcareous; moderately alkaline (pH 8.4).
TYPE LOCATION: San Juan County, Utah; about 2 miles southeast of Aneth Community; 1,000 feet south and 300 feet west of the northeast corner, sec. 27, T. 41 S., R. 25 E.
RANGE IN CHARACTERISTICS:
Soil moisture intermittently moist in some parts during July to October and December to March. Driest during May and June. Typic aridic soil moisture regime.
Mean annual soil temperature: 53 to 59 degrees F.
Mean summer soil temperature: 74 to 79 degrees F.
Depth to bedrock: 40 to 60 inches or more
Depth to calcic horizon: 20 to 40 inches calcareous in all parts above the calcic horizon
Particle-size control section
Clay content: 8 to 18 percent
Rock fragments: 0 to 5 percent
Reaction: moderately alkaline or strongly alkaline
A horizon
Hue: 7.5YR, 5YR, 2.5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 4 to 6, dry or moist
Bw horizon
Hue: 7.5YR, 5YR, 2.5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 4 to 6, dry or moist
Texture: loamy fine sand to very fine sandy loam, fine sandy loam, sandy loam
Bk horizon
Hue: 5YR, 7.5YR
Value: 5 to 8 dry, 4 to 7 moist
Chroma: 2 to 6, dry or moist
Texture: sandy loam, fine sandy loam, very fine sandy loam
COMPETING SERIES: These are the Bluechief (UT), Boreham (UT), Hiko Springs (UT), Kaito (AZ), Kinan (AZ), McCutchen (NV), Moffat (UT), Nakoy (UT), Nolava (UT), Nuahs (NV), Pagina (AZ), Riemod (UT), and Trook (WY) series. Bluechief soils have bedrock at depths of 30 to 40 inches and a calcic horizon within 25 inches. Boreham, Hiko Springs, McCutchen, Nolava, Riemod, and Trook soils have hue of 7.5YR or yellower. Nakoy soils have a mean annual soil temperature of less than 51 degrees F. Kaito soils have a paralithic contact at 40 to 60 inches. Kinan and Nuahs soils have 5 to 35 percent rock fragments in the particle-size control section. McCutchen soils also have a lithologic discontinuity below 40 inches. Moffat soils have a calcic horizon within 20 inches. Pagina soils have a paralithic contact from 20 to 40 inches. In addition, Hiko Springs, McCutchen, and Nuahs soils are in the Great Basin Desert (MLRAs 28A, 28B, 29) and are moist for short periods in winter and early spring and intermittently moist for 10 to 20 days cumulative from July through September
GEOGRAPHIC SETTING: Nakai soils are on river terraces, sand sheets on structural benches, fans and broad valleys at elevations of 3,700 to 6,100 feet. Slopes are 0 to 15 percent. The climate is arid. These soils formed in mixed moderately coarse textured alluvium and eolian material. The mean annual air temperature is about 52 to 57 degrees F., and the mean summer temperature is about 77 degrees F. The average annual precipitation is 5 to 10 inches. Freeze-free period is about 130 to 200 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Moffat soils and the Aneth, Deleco, Neskahi and Whit soils. Aneth and Neskahi soils lack a calcic horizon. Deleco soils have a petrocalcic horizon within depth of 20 inches. Whit soils have less than 15 percent coarser than very fine sand in the particle-size control section.
DRAINAGE AND PERMEABILITY: Well drained; slow and medium runoff; moderately rapid permeability.
USE AND VEGETATION: Used primarily for livestock grazing. The potential vegetation is Indian ricegrass, galleta grass, dropseed, snakeweed, Mormon-tea, and Russian thistle.
DISTRIBUTION AND EXTENT: Southeastern Utah and northern Arizona. The series is extensive. MLRA 35.
MLRA OFFICE RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Aneth Area, San Juan County, Utah, 1972.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon -the zone from 0 to 5 inches (A horizon)
Cambic horizon -the zone from 5 to 21 inches (Bw horizons)
Calcic horizon -the zone from 21 to 34 inches (Bk1 and Bk2 horizons)
Classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, Tenth Edition, 2006.
Formerly classified as Typic Calciorthids
Updates and revisions for the correlation of Navajo Mountain Area (AZ711), June 24, 2008, CEM
ADDITIONAL DATA: Laboratory sample number S82UT-037-007