LOCATION OJITO NMEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Ustic Haplocambids
TYPICAL PEDON: Ojito loamy very fine sand--on a shoulder of a ridge sloping 16 percent to the west at 6,020 feet elevation--rangeland. (Colors are for dry soil unless otherwise noted. When described, the soil was slightly moist from 4 to 10 inches and otherwise dry throughout.)
A--0 to 3 inches; brown (7.5YR 5/3) loamy very fine sand, brown (7.5YR 4/3) moist; moderate very thick platy structure parting to moderate coarse granular; soft, very friable, slightly sticky and nonplastic; few coarse, few fine, and many very fine roots; few very fine irregularly shaped pores; slightly effervescent; slightly alkaline (pH 7.6); clear smooth boundary. (2 to 4 inches thick)
Bk1--3 to 10 inches; light brown (7.5YR 6/3) loamy very fine sand, brown (7.5YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; few coarse, few medium, few fine, and common very fine roots; few fine and few very fine tubular pores; 2 percent gravel; strongly effervescent, secondary calcium carbonate segregated as few fine irregularly shaped coats on rock fragments; moderately alkaline (pH 8.0); clear wavy boundary. (5 to 12 inches thick)
Bk2--10 to 18 inches; light brown (7.5YR 6/4) loamy very fine sand, brown (7.5YR 4/4) moist; moderate coarse subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; few coarse, few medium, few fine, and common very fine roots; few fine and few very fine tubular pores; 2 percent gravel; strongly effervescent, secondary calcium carbonate segregated as few fine irregularly shaped coats on rock fragments; moderately alkaline (pH 8.0); clear wavy boundary. (6 to 13 inches thick)
2BCk1--18 to 25 inches; light brown (7.5YR 6/4) very fine sandy loam, brown (7.5YR 4/4) moist; weak coarse subangular blocky structure; soft, very friable, slightly sticky and nonplastic; few coarse, few medium, few fine, and common very fine roots; few fine and few very fine irregularly shaped pores; 10 percent gravel; strongly effervescent, secondary calcium carbonate segregated as few fine irregularly shaped coats on rock fragments; moderately alkaline (pH 8.2); abrupt wavy boundary. (5 to 12 inches thick)
3BCk2--25 to 35 inches; light brown (7.5YR 6/3) and pinkish gray (7.5YR 7/2) very paragravelly very fine sand, brown (7.5YR 5/4) and light brown (7.5YR 6/4) moist; massive, platy rock structure; slightly hard, friable, nonsticky and nonplastic; few medium, few fine, and few very fine roots; few very fine irregularly shaped pores; 50 percent sandstone paragravel; slightly and strongly effervescent, secondary calcium carbonate segregated as few fine and medium irregularly shaped coats on pararock fragments; moderately alkaline (pH 8.0); clear smooth boundary. (4 to 10 inches thick)
3Cr--35 to 45 inches; interbedded weakly cemented micaceous sandstone and siltstone bedrock.
TYPE LOCATION: Santa Fe County, New Mexico; on the Pojoaque Indian Reservation about 2 miles northeast of Pojoaque; 500 feet north and 4,600 feet east of the southwest corner of section 32, T.20N., R.9E.; USGS Espanola 7.5 minute topographic quadrangle; Latitude 35 degrees 54 minutes 54 seconds North and Longitude 106 degrees 0 minutes 8 seconds West, NAD 27.
RANGE IN CHARACTERISTICS:
Soil moisture - The soil moisture control section is intermittently moist in some part from July to October and December to March. The soils are driest in May and June. The soil moisture regime is aridic bordering on ustic.
Mean annual soil temperature - 52 to 54 degrees F.
Depth to paralithic contact - 20 to 40 inches
Depth to base of cambic horizon - 15 to 29 inches
Volcanic glass content: 5 to 15 percent in the coarse silt plus sand fraction
Lithology of rock fragments: sandstone
Reaction - slightly alkaline in the surface; moderately alkaline in the subsoil and substratum
Salinity, mmhos/cm - 0 to 4
Sodicity, SAR - 0 to 13
Particle-size control section (weighted averages)
Silicate clay content: 2 to 12 percent
Sand content: 60 to 90 percent
Fine sand or coarser content: 20 to 35 percent
Rock fragment content: 5 to 10 percent gravel
Mica content: 1 to 5 percent (by grain count)
A horizon
Value: 5 or 6 dry
Chroma: 3 or 4, dry or moist
Rock fragments: 0 to 10 percent gravel
Bk horizons
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 or 4, dry or moist
Texture: loamy very fine sand or fine sandy loam
Rock fragments: 5 to 10 percent gravel
Calcium carbonate equivalent: 1 to 5 percent
2BCk horizon
Value: 4 or 5 moist
Chroma: 3 or 4, dry or moist
Texture: very fine sandy loam, loamy very fine sand, or very fine sand
Rock fragments: 5 to 10 percent gravel
Calcium carbonate equivalent: 1 to 5 percent
Other features: some pedons contain 5 to 10 percent paragravel
3BCk horizons
Value: 5 through 7 dry, 4 through 6 moist
Chroma: 2 through 4, dry or moist
Texture: very fine sand, loamy very fine sand, or very fine sandy loam; some pedons have strata or thin subhorizons of gravelly coarse sand or gravelly loamy sand
Rock fragments: 0 to 10 percent gravel
Pararock fragments: 10 to 50 percent weakly cemented sandstone or siltstone paragravel, some of which will slake in water
Calcium carbonate equivalent: 1 to 5 percent
COMPETING SERIES: These are the
Begay,
Delvalle,
Ignacio,
Kitsili,
Koshare,
Parida,
Remmit,
Sandspring, and
Turnback series.
Begay, Delvalle, Kitsili, Koshare, Parida, Remmit, and Sandspring soils are all deeper than 40 inches to bedrock.
Ignacio soils are moderately deep to a lithic contact.
Turnback soils have hues of 10YR and 2.5Y and do not have significant amounts of mica in the silt and sand fractions.
In addition, Remmit and Turnback soils are in the Western Great
Plains (LRR-G MLRAs 67, 58B) and are more moist in
May and June.
GEOGRAPHIC SETTING: Ojito soils are on beveled summits, shoulders, and footslopes of ridges and hills. They formed in eolian material, alluvium, and residuum derived from Tertiary micaceous sandstone and siltstone. Slopes are 5 to 25 percent. Elevation ranges from 5,400 to 6,600 feet. The mean annual precipitation is 9 to 12 inches with about 45 percent falling as rain from high-intensity convective thunderstorms between July and September. The mean annual air temperature is 50 to 52 degrees F. The frost-free period is 150 to 170 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Koshare soil and the Innacutt, Quarteles, El Rancho, and Walkibout soils. Innacutt soils are very deep, do not have diagnostic horizons, and occur on inset fans and narrow flood plains of gulches. Koshare soils are very deep and occur on adjacent toeslopes. Quarteles soils are loamy, very shallow to soft bedrock, do not have diagnostic subsurface horizons, and occur on adjacent backslopes. El Rancho soils are fine-silty, very deep, and occur on toeslopes of ridges and hills. Walkibout soils are coarse-silty, very deep, and occur on side slopes of gulches.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; low surface runoff; moderately rapid permeability.
USE AND VEGETATION: Ojito soils are used for urban development, livestock grazing, and recreation. The historic climax vegetation is Indian ricegrass, other shrubs, New Mexico feathergrass, and sand dropseed. The ecological site is Sandy Slopes(R036XB111NM).
DISTRIBUTION AND EXTENT: Ojito soils are of moderate extent on the southeastern Espanola Basin part of the Basin and Range province in northcentral New Mexico. The MLRA is 36.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Santa Fe County, New Mexico; Santa Fe Area Soil Survey Update; 2008. Ojito is a local Spanish place name.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to a depth of about 3 inches. (A horizon)
Cambic horizon - The zone from 3 to about 25 inches. (Bk1, Bk2, and 2BCk1 horizons)
Paralithic contact - The boundary at about 35 inches to weakly cemented bedrock. (3Cr layer)
Particle-size control section - The zone from 10 to 35 inches (Bk2, 2BCk1, 3BCk2 horizon)
Series control section - The zone from 0 to 45 inches.
Classified according to Keys to Soil Taxonomy Tenth Edition, 2006.