LOCATION BRIMHALL NMEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Typic Calcigypsids
TYPICAL PEDON: Brimhall loamy fine sand -- rangeland. (Colors are for dry soil unless otherwise noted. When described, the soil was slightly moist from 5 to 49 inches.)
A--0 to 2 inches; yellowish brown (10YR 5/4) loamy fine sand, dark yellowish brown (10YR 4/4) moist; weak thin platy structure parting to weak fine granular; soft, very friable, slightly sticky and nonplastic; few fine and very fine roots; 5 percent gravel; strongly effervescent; slightly alkaline (pH 7.8); clear smooth boundary. (2 or 3 inches thick)
2Bw--2 to 5 inches; light yellowish brown (10YR 6/4) fine sandy loam, dark yellowish brown (10YR 4/4) moist; weak coarse and moderate medium subangular blocky structure; soft, very friable, slightly sticky and nonplastic; common medium, fine and very fine roots; common very fine discontinuous tubular pores; 5 percent gravel and channers; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (0 to 5 inches thick)
2Bk1--5 to 11 inches; light yellowish brown (10YR 6/4) fine sandy loam, dark yellowish brown (10YR 4/4) moist; moderate coarse subangular blocky structure; soft, very friable, slightly sticky and nonplastic; few medium and common fine and very fine roots; common very fine tubular pores; 5 percent gravel and channers; violently effervescent, secondary calcium carbonate disseminated and also segregated in few fine irregularly shaped seams and as coatings on undersides of rock fragments; moderately alkaline (pH 8.4); clear smooth boundary. (6 to 8 inches thick)
2Bk2--11 to 21 inches; very pale brown (10YR 7/3) fine sandy loam, light yellowish brown (10YR 6/4) moist; moderate coarse subangular blocky structure; slightly hard, friable, slightly sticky and nonplastic; common fine and very fine roots; few very fine tubular pores; 5 percent gravel; violently effervescent, secondary calcium carbonate disseminated and also segregated in common fine and medium irregularly shaped soft masses and as coatings on rock fragments; moderately alkaline (pH 8.2); clear wavy boundary. (8 to 10 inches thick)
3Bky--21 to 29 inches; white (10YR 8/1) gypsiferous fine sandy loam, very pale brown (10YR 7/3) moist; moderate coarse subangular blocky structure; slightly hard, friable, slightly sticky and nonplastic; few medium and common fine and very fine roots; few very fine discontinuous irregularly shaped pores; 5 percent gravel and channers; secondary silt-sized gypsum crystals disseminated and also segregated in common fine irregularly shaped masses and as coatings on rock fragments; strongly effervescent, secondary calcium carbonates disseminated and also segregated in few fine irregularly shaped seams; moderately alkaline (pH 8.2); gradual smooth boundary. (7 to 12 inches thick)
3By--29 to 38 inches; very pale brown (10YR 8/2) gypsiferous fine sandy loam, light yellowish brown (10YR 6/4) moist; weak coarse subangular blocky structure; slightly hard, friable, slightly sticky and nonplastic, few fine and common very fine roots; few very fine discontinuous irregularly shaped pores; 5 percent channers and 5 percent gravel; secondary silt-sized gypsum crystals disseminated and also segregated in many fine irregularly shaped masses and as coatings on rock fragments, primary sand-sized gypsum crystals in few fine masses; slightly effervescent; moderately alkaline (pH 7.9); clear wavy boundary. (8 to 10 inches thick)
3BCy--38 to 49 inches; very pale brown (10YR 7/4) channery gypsiferous fine sandy loam, yellowish brown (10YR 5/4) moist; weak coarse and medium subangular blocky structure; soft, very friable, slightly sticky and nonplastic; few medium, fine and very fine roots; few very fine discontinuous irregularly shaped pores; many thin strata of soft sandstone fragments; 15 percent channers and 5 percent gravel; secondary silt-sized gypsum crystals segregated in few fine irregularly shaped masses and as coatings on undersides of rock fragments; primary sand-sized gypsum crystals present in common fine masses; moderately alkaline (pH 8.2); clear wavy boundary. (9 to 12 inches thick)
3Cr--49 inches; soft sandstone bedrock with thin strata of soft gypsiferous shale.
TYPE LOCATION: San Juan County, New Mexico; on the Navajo Indian Reservation about 6 miles northeast of Sheep Springs; 2,075 feet north and 1,000 feet east of the southwest corner of sec. 26, T.23N., R.17W; Latitude 36 degrees 11 minutes 48 seconds N and Longitude 108 degrees 37 minutes 35 seconds W.
RANGE IN CHARACTERISTICS:
Soil moisture - Typically the soil moisture control section is intermittently moist in some part from July to September and December to March. The soil moisture control section is dry in all parts greater than 75 percent of the time (cumulative) that the soil temperature at 20 inches is greater than 41 degrees F. Typic aridic moisture regime.
Soil temperature - 54 to 57 degrees F.
Silicate clay content, control section weighted average - 8 to 18 percent
Reaction - slightly to moderately alkaline
Depth to calcic horizon - 2 to 16 inches
Depth to gypsic horizon - 16 to 35 inches
Soil depth - 40 to 60 inches to soft bedrock
Rock fragments are hard sandstone and siderite (iron carbonate)
A horizon
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 or 4, dry or moist
Bw and Bk horizons
Value: 6 through 8 dry, 4 through 6 moist
Chroma: 2 through 4, dry or moist
Rock fragments: 0 to 5 percent gravel, 0 to 5 percent channers
Calcium carbonate equivalent: 5 to 20 percent by weight, 5 to 30 percent by volume, secondary accumulations
Other features: some pedons contain thin layers which are gravelly or have textures of loamy sand, sandy clay loam or loam
Bky horizon
Hue: 10YR, 2.5Y
Value: 7 or 8 dry, 6 or 7 moist
Chroma: 2 through 4, dry or moist
Calcium carbonate equivalent: 5 to 10 percent
Salinity, dS/m: 2 to 4
Sodicity, SAR: 0 to 5
Gypsum content: 1 to 5 percent
By horizon
Hue: 10YR, 2.5Y, N (neutral)
Value: 7 or 8 dry, 5 through 7 moist
Chroma: 2 through 4, dry or moist
Texture: gypsiferous fine sandy loam, gypsiferous sandy loam
Rock fragments: 0 to 5 percent gravel, 5 to 10 percent channers
Calcium carbonate equivalent: 1 to 5 percent by weight, 0 to 5 percent by volume visible secondary accumulations.
Salinity, dS/m: 4 to 16
SAR: 5 to 35
Gypsum content: 15 to 30 percent, present dominantly as silt-sized secondary crystals
Other features: some pedons contain thin layers which are channery or have textures of loamy fine sand or loam
BCy and Cy horizons
Hue: 10YR, 2.5Y
Value: 6 through 8 dry, 5 or 6 moist
Chroma: 2 through 4, dry or moist
Texture: channery gypsiferous fine sandy loam, channery gypsiferous sandy loam
Rock fragments: 0 to 5 percent gravel, 15 to 30 percent channers (5 percent are larger than 3")
Salinity, dS/m: 4 to 16
SAR: 5 to 35
Gypsum content: 15 to 30 percent
Other features: some pedons contain thin layers of channery loam or very channery fine sandy loam; 15 to 35 percent soft sandstone fragments
COMPETING SERIES: These are Peagre (CO) (T) and Roboost series. Peagre soils have hard bedrock at depths of 20 to 40 inches and mean annual soil temperatures of 52 to 54 degrees F. Robroost soils are very deep and have 5YR or 7.5YR hues.
GEOGRAPHIC SETTING: Brimhall soils are on knolls of mesas and structural benches. Brimhall soils formed in eolian material, alluvium, and residuum derived from sandstone and some shale. Slopes are 1 to 3 percent. Elevation ranges from 5,500 to 5,800 feet. The mean annual precipitation is 5 to 8 inches with 35 to 60 percent falling as rain from high-intensity thunderstorms between July and September. The mean annual air temperature is 51 to 54 degrees F. The average frost-free period is 140 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Benally, Genats, and Werito soils. Benally soils are fine-loamy, have natric horizons, and occur in adjacent depressions. Genats soils lack diagnostic horizons, are moderately deep, and occur on adjacent backslopes. Werito soils are fine textured, moderately deep, and occur on adjacent footslopes.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff, moderately rapid permeability.
USE AND VEGETATION: Brimhall soils are used for livestock grazing. Present vegetation is alkali sacaton, galleta, Indian ricegrass, winterfat, shadscale, and Russian thistle.
DISTRIBUTION AND EXTENT: Brimhall soils are of small extent on the Colorado Plateau province in northwest New Mexico. LRR-D; MLRA 35.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Shiprock Area, Parts of San Juan County, New Mexico and Apache County, Arizona; 1993.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 5 inches (A and 2Bw horizons)
Calcic horizon - the zone from 5 to 21 inches (2Bk1 and 2Bk2 horizons)
Gypsic horizon - the zone from 29 to 49 inches (3By and 3BCy horizons)
Paralithic contact - the boundary with soft sandstone bedrock at 49 inches (3Cr horizon)
Soils classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, Tenth Edition, 2006.
ADDITIONAL DATA: The series type location had reference samples analyzed at the National Soil Survey Laboratory (NSSL), for sodium adsorption ratio, calcium carbonate equivalent, and percent gypsum, as pedon S84NM-045-004. Calcium carbonate equivalence was also determined with a field volume calcimeter. Salinity values were determined on two pedons, including the type location, with a Wheatstone bridge. Another pedon of this series was sampled for full characterization by the NSSL as pedon S85NM-045-014 (Fort Defiance SSA).
Updates and revisions for MLRA consistency, February 26, 2008, DWD.