LOCATION MESA                    CO+AZ NM UT

Established Series
Rev. AJC/CRP/JCK
12/2017

MESA SERIES

The Mesa series consists of very deep, well drained soils that formed in slope alluvium and alluvium. Mesa soils are on stream terraces, fan remnants, mesas, and pediments. Slopes are 0 to 12 percent. Mean annual precipitation is about 203 mm, and mean annual temperature is about 11 degrees C.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Calciargids

TYPICAL PEDON: Mesa loam - grassland. (Colors are for dry soil unless otherwise noted.)

A--0 to 10 cm; pinkish gray (7.5YR 6/2) loam, brown (7.5YR 4/2) moist; strong fine granular structure, moderate thin platy in the upper 1 cm; soft, very friable, slightly sticky and slightly plastic; 10 percent gravel; slightly alkaline (pH 7.6); gradual smooth boundary. (8 to 32 cm thick)

Bt--10 to 36 cm; light brown (7.5YR 6/3) clay loam, brown (7.5YR 4/3) moist; moderate fine prismatic structure parting to fine subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; many distinct clay films on faces of peds and on surfaces along root channels and pores; 10 percent gravel; slightly effervescent; moderately alkaline (pH 8.0); gradual smooth boundary. (0 to 48 cm thick)

Btk--36 to 51; pink (7.5YR 7/4) clay loam, brown (7.5YR 5/4) moist; weak medium prismatic structure parting to fine subangular blocky; slightly hard, very friable, slightly sticky and slightly plastic; few distinct clay films on faces of peds and on surfaces along root channels and pores; calcium carbonate concretions and carbonate coats on rock fragments; 10 percent gravel; strongly effervescent; moderately alkaline (pH 8.2); gradual smooth boundary. (10 to 84 cm thick)

BCk1--51 to 89 cm; pink (7.5YR 8/3) very gravelly loam, light brown (7.5YR 6/4) moist; massive; hard, friable, slightly sticky and slightly plastic; many prominent calcium carbonate concretions and masses, and many carbonate coats on rock fragments; 40 percent gravel and cobbles; violently effervescent; moderately alkaline (pH 8.4); diffuse wavy boundary. (0 to 53 cm thick)

BCk2--89 to 152 cm; pink (7.5YR 7/3) very gravelly loam, light brown (7.5YR 6/4) moist; massive; hard, very friable, slightly sticky and slightly plastic; common distinct calcium carbonate concretions and carbonate coats on rock fragments; 70 percent gravel and cobbles; violently effervescent; moderately alkaline (pH 8.4).

TYPE LOCATION: Montrose County, Colorado; approximately 161 meters south and 402 meters east of center of Sec. 21, T. 49 N., R. 10 W.; Montrose West USGS quad; lat. 38 degrees 29 minutes 41 seconds N. and long. 107 degrees 59 minutes 24 seconds W., NAD 27

RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 11 to 14 degrees C
Particle-size control section (weighted average):
Clay content (non-carbonate) - 18 to 35 percent
Rock fragments - 0 to 35 percent gravel and cobbles

A or Ap horizon
Hue: 7.5YR, 10YR or 2.5Y
Value: 5, 6, 7 or 8 dry; 3, 4, 5, 6 or 7 moist
Texture: fine sandy loam, clay loam, loam or sandy clay loam
Clay content: 12 to 35 percent
Rock fragments: 0 to 35 percent - 0 to 35 percent gravel; 0 to 15 percent cobbles
Sodium adsorption ratio: 0 to 4
Reaction: 7.4 to 8.0

Bt horizon (where present)
Hue: 7.5YR or 10YR
Value: 5, 6, 7 or 8 dry; 4, 5, 6, or 7 moist
Chroma: 2, 3, 4 or 6 dry or moist
Texture: clay loam, sandy clay loam or loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 35 percent - 0 to 35 percent gravel; 0 to 15 percent cobbles
Gypsum content: 0 to 4 percent
Sodium adsorption ratio: 0 to 4
Reaction: pH 7.4 to 8.0

Btk horizon
Hue: 7.5YR or 10YR
Value: 5, 6, 7 or 8 dry; 4, 5, 6, or 7 moist
Chroma: 2, 3, 4 or 6 dry or moist
Texture: clay loam, silty clay loam, sandy clay loam, loam, sandy loam or clay
Clay content (non-carbonate): 18 to 35 percent
Rock fragments: 0 to 35 percent - 0 to 35 percent gravel; 0 to 15 percent cobbles
Calcium carbonate equivalent: 15 to 40 percent
Gypsum content: 0 to 4 percent
Electrical conductivity: 0 to 4 percent mmhos/cm
Sodium adsorption ratio: 0 to 4
Reaction: pH 8.0 to 8.6

BCk horizons
Hue: 7.5YR or 10YR
Value: 6, 7, or 8 dry, 5, 6 or 7 moist
Chroma: 3, 4 or 6 dry or moist
Texture: fine sandy loam, sandy loam, loam, sandy clay loam, clay loam or clay
Clay content (non-carbonate): 10 to 35 percent
Rock fragments: 35 to 80 percent - 35 to 80 percent gravel; 0 to 50 percent cobbles; 0 to 15 percent stones
Calcium carbonate equivalent: 5 to 50 percent
Gypsum content: 0 to 4 percent
Electrical conductivity: 0 to 8 percent mmhos/cm
Sodium adsorption ratio: 0 to 10
Reaction: pH 8.0 to 8.8

Some pedons have a Bk above, or in place of, the BCk horizon.

COMPETING SERIES:
Cataract (UT) - are moderately deep to a lithic contact
Chattin (ID) - have a lithologic discontinuity; have volcanic glass
Grieta (NM) - have less than 35 percent rock fragments in the lower part of the subsoil
Mack (CO) - have less than 35 percent rock fragments in the lower part of the subsoil
Nannyton (ID) - have a lithologic discontinuity; have less than 35 percent rock fragments in the lower part of the subsoil
Neiberger (CO) - are moderately deep to a paralithic contact

GEOGRAPHIC SETTING:
Landform - stream terraces, fan remnants, mesas, and pediments
Elevation - 1,372 to 1.768 meters
Slope - 0 to 12 percent
Parent material - slope alluvium or alluvium
Mean annual temperature - 10.0 to 12.8 degrees C
Mean annual precipitation - 152 to 229 mm
Precipitation pattern - significant increases in spring, late summer and early fall
Frost-free period - 140 to 180 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Fruita soils and Mack soils.

DRAINAGE AND PERMEABILITY: Well drained; moderate and moderately slow permeability.

USE AND VEGETATION: Mesa soils are used for native pasture, irrigated cropland, or orchards. Native vegetation is Indian ricegrass, shadscale saltbush, winterfat, James' galleta, and squirreltail.

DISTRIBUTION AND EXTENT: Mesa soils are of moderate extent in southwestern Colorado, southeastern Utah, northwestern New Mexico, and northeastern Arizona. MLRA 34B and 35.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Grand Junction Area, Colorado, 1905.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon from - 0 to 10 cm (A horizon)
Argillic horizon from - 10 to 51 cm (Bt and Btk horizons)
Calcic horizon from - 36 to 152 cm (Btk, BCk1 and BCk2 horizons)
Particle size control section from - 10 to 51 cm (Bt and Btk horizons)

Mesa soils have a mesic soil temperature regime and an aridic soil moisture regime.

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National Cooperative Soil Survey
U.S.A.