LOCATION ARMENTA NMEstablished Series
TAXONOMIC CLASS: Ashy-pumiceous, glassy, mesic Vitritorrandic Haplustolls
TYPICAL PEDON: Armenta very paragravelly ashy coarse sand--on a footslope of an interfluve sloping 8 percent to the southeast at 6,275 feet elevation--pinyon-juniper forestland. (Colors are for dry soil unless otherwise noted. When described on September 20, 2000, the soil was dry throughout.) Surface is covered with 55 percent pumice paragravel.
A--0 to 2 inches; grayish brown (10YR 5/2) very paragravelly ashy coarse sand, very dark grayish brown (10YR 3/2) moist; single grain; loose, nonsticky and nonplastic; few fine and common very fine roots; 45 percent paragravel; neutral (pH 6.9); clear smooth boundary. (2 to 5 inches thick)
Bw--2 to 10 inches; brown (10YR 5/3) very paragravelly ashy coarse sandy loam, dark brown (10YR 3/3) moist; weak very fine subangular blocky structure; soft, very friable, slightly sticky and nonplastic; common coarse, few medium, common fine, and common very fine roots; 45 percent paragravel; slightly acid (pH 6.4); clear smooth boundary. (5 to 11 inches thick)
Bk--10 to 13 inches; pale brown (10YR 6/3) very paragravelly ashy coarse sand, dark yellowish brown (10YR 4/4) moist; single grain; loose, nonsticky and nonplastic; common medium, few coarse, few fine, and few very fine roots; 55 percent paragravel; noneffervescent matrix, strongly effervescent in few fine irregularly shaped concretions of secondary calcium carbonate (1 percent calcium carbonate equivalent); neutral (pH 7.2); abrupt wavy boundary. (5 to 15 inches thick)
E and Bt--13 to 55 inches; white (N 8/0) extremely paragravelly ashy coarse sand (E), white (N 8/0) moist; single grain; loose, nonsticky and nonplastic; common medium, few fine and few very fine roots; few, thin (0.5 to 1 cm thick), continuous very pale brown (10YR 7/3) lamellae (Bt), light yellowish brown (10YR 6/4) moist, total thickness is 8 cm; 70 percent pumice paragravel; neutral (pH 7.3); gradual wavy boundary. (20 to 45 inches thick)
C--55 to 80 inches; white (N 8/0) extremely paragravelly ashy coarse sand, white (N 8/0) moist; single grain; loose, nonsticky and nonplastic; few fine and few very fine roots; 80 percent pumice paragravel; neutral (pH 7.3).
TYPE LOCATION: Bandelier National Monument, Sandoval County, New Mexico; 9.42 miles south of Los Alamos city pond; USGS Frijoles 7.5 minute topographic quadrangle; Latitude 35 degrees 44 minutes 46.42 seconds North and Longitude 106 degrees 16 minutes 27.28 seconds West, NAD 27.
RANGE IN CHARACTERISTICS:
Soil moisture - The soil moisture control section is moist in all parts during the 60 days following the winter solstice. It is moist in some part less than 40 percent and moist in all parts less than 25 percent of the time when the soil temperature at 20 inches is above 41 degrees F. The soils are driest in May and June. The soil moisture regime is ustic bordering on aridic.
Average annual soil temperature - 51 to 53 degrees F.
Thickness of mollic epipedon - 10 to 14 inches
Depth to calcareous material (as visible secondary calcium carbonate) - 7 to 13 inches
Oxalate extractable Al + 1/2Fe: .01 to .10 percent (estimated)
Particle-size control section:
Paragravel content (pumice fragments): 45 to 85 percent
Volcanic glass content: 70 to 95 percent in the coarse silt plus sand fraction
A horizon
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 2 or 3, dry or moist
Clay content: 2 to 8 percent
Pararock fragments: 40 to 60 percent paragravel
Bw horizon (a Bt horizon in some pedons)
Hue: 10 YR or 7.5 YR
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 2 to 4 dry, 2 or 3 moist
Texture: very paragravelly or extremely paragravelly--ashy loamy coarse sand, ashy loamy sand, or ashy coarse sandy loam
Clay content: 6 to 14 percent
Sand content: 60 to 80 percent
Pararock fragments: 45 to 70 percent paragravel
Reaction: slightly acid or neutral
Bk horizons
Value: 6 or 7 dry, 4 to 6 moist
Chroma: 2 or 3 dry, 2 to 4 moist
Texture: very paragravelly ashy coarse sand or extremely paragravelly ashy coarse sand
Clay content: 1 to 6 percent
Sand content: 80 to 95 percent
Pararock fragments: 50 to 70 percent paragravel
Calcium carbonate equivalent: 1 to 2 percent
Salinity, mmhos/cm: 0 to 2
Sodicity, SAR: 0 to 4
Volcanic glass content: 70 to 90 percent in the coarse silt plus sand fraction
E and Bt horizons
Value: 7 or 8, dry or moist
Chroma: 0 to 2, dry or moist
Clay content: 1 to 6 percent
Sand content: 80 to 95 percent
Salinity, mmhos/cm: 0 to 2
Sodicity, SAR: 0 to 4
Pararock fragments: 60 to 80 percent paragravel
Volcanic glass content: 80 to 95 percent in the coarse silt plus sand fraction
C horizons
Value: 7 or 8, dry or moist
Chroma: 0 to 2, dry or moist
Clay content: 0 to 4 percent
Salinity, mmhos/cm: 0 to 2
Sodicity, SAR: 0 to 4
Pararock fragments: 65 to 85 percent paragravel
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Armenta soils are on backslopes, footslopes, and toeslopes of interfluves on undulating plateaus. They formed in slope alluvium derived from air-fall pumice of the Quaternary Age Cajete Member. Slopes are 3 to 20 percent. Elevation ranges from 5,400 to 7,000 feet. The mean annual precipitation is 12 to 14 inches with about 45 percent falling as rain from high-intensity convective thunderstorms between July and September. The mean annual air temperature is 49 to 51 degrees F. The frost-free period is 140 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Canuela, Hackroy, and Chiminet soils. Canuela soils are loamy, shallow to bedrock, have an argillic horizon, and occur on beveled summits of interfluves. Hackroy soils are clayey, shallow to bedrock, have an argillic horizon, and are on summits of interfluves. Chiminet soils are loamy, very shallow to bedrock, and are on shoulders and backslopes of interfluves.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; low surface runoff; moderately rapid permeability in the upper part and very rapid in the lower part.
USE AND VEGETATION: Armenta soils are used for and recreation and wildlife habitat. The historic climax vegetation is ponderosa pine, Gambel's oak, mountain muhly, and muttongrass. The ecological site is Pinus edulis/Rhus trilobata/Bouteloua gracilis (F036XB133NM).
DISTRIBUTION AND EXTENT: Armenta soils are of small extent on the southwestern 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. Series proposed in Sandoval County, New Mexico; Bandelier National Monument Soil Survey; 2000. Armenta is a street name in Santa Fe.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to a depth of about 10 inches. (A and Bw horizons)
Vitritorrandic feature - Based on both the content of pumice and on the estimated content of volcanic glass throughout the upper 30 inches (A, Bw, Bk, and part of E and Bt horizons).
Taxonomic version: Classified according to Keys to Soil Taxonomy, Tenth Edition, 2006.
ADDITIONAL DATA: Calcium carbonate equivalence was determined using a calcimeter.