LOCATION MEDRANO NMEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic, shallow Argiduridic Durustolls
TYPICAL PEDON: Medrano extremely gravelly loam, stony--on a cinder cone sloping 33 percent to the northwest at 6,670 feet elevation--rangeland. (Colors are for dry soil unless otherwise noted. When described, the soil was dry throughout.)
A--0 to 3 inches; brown (7.5YR 5/3) extremely gravelly loam, dark brown (7.5YR 3/3) moist; weak fine granular structure; soft, very friable, slightly sticky and nonplastic; many fine and common very fine roots; many very fine interstitial pores; 55 percent gravel, 10 percent cobbles, and 1 percent stones; neutral (pH 7.2); abrupt smooth boundary. (1 to 3 inches thick)
Bt1--3 to 7 inches; brown (7.5YR 4/3) very gravelly loam, dark brown (7.5YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; common fine and common very fine roots; few fine and few very fine tubular pores; few faint clay films on faces of peds; 35 percent gravel and 5 percent cobbles; neutral (pH 7.2); clear smooth boundary. (3 to 6 inches thick)
Bt2--7 to 10 inches; reddish brown (5YR 4/4) very gravelly clay loam, dark brown (7.5YR 3/4) moist; moderate fine subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few medium, common fine, and common very fine roots; few fine and common very fine tubular pores; few distinct and many faint clay films on faces of peds; 40 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.6); abrupt smooth boundary. (3 to 7 inches thick)
Btk--10 to 14 inches; light brown (7.5YR 6/4) very gravelly clay loam, brown (7.5YR 5/4) moist; moderate fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few medium, few fine and common very fine roots; few fine and few very fine tubular pores; few faint clay films on faces of peds; 50 percent gravel and 5 percent cobbles; violently effervescent, secondary calcium carbonate segregated as many coarse irregularly shaped accumulations on faces of peds and on rock fragments; strongly alkaline (pH 8.6); clear smooth boundary. (3 to 7 inches thick)
Bk--14 to 19 inches; pink (7.5YR 8/4) very gravelly loam, light brown (7.5YR 6/3) moist; moderate medium platy structure; soft, very friable, slightly sticky and nonplastic; few medium, few fine, and few very fine roots; few fine and few very fine tubular pores; 30 percent gravel and 5 percent cobbles; violently effervescent, secondary calcium carbonate finely disseminated throughout the matrix and as coarse irregularly shaped accumulations on rock fragments; strongly alkaline (pH 8.6); abrupt wavy boundary. (4 to 12 inches thick)
Bkqm--19 to 30 inches; white (7.5YR 8/1) duripan, pink (7.5YR 7/3) moist; moderate very thick platy structure; extremely hard and extremely firm; very strongly cemented; matrix is cemented by secondary silica; violently effervescent, matrix is impregnated and partially cemented with secondary calcium carbonate; strongly alkaline (pH 8.8); abrupt wavy boundary. (8 to 15 inches thick)
2BCky1--30 to 49 inches; reddish brown (2.5YR 4/4) cinders, dark red (2.5YR 3/6) moist; fine earth is coarse sand with 0 percent clay; single grain; loose, nonsticky and nonplastic; few fine and few very fine roots; common course and few medium irregularly shaped pores; 95 percent gravel; secondary calcium sulfate segregated as few coarse irregular shaped accumulations on the undersides of rock fragments; slightly effervescent, secondary calcium carbonate segregated as many fine and medium irregularly shaped accumulations on rock fragments; strongly alkaline (pH 8.6); clear wavy boundary. (18 to 25 inches thick)
2BCky2--49 to 80 inches; red (2.5YR 4/6) cinders, dark red (2.5YR 3/6) moist, fine earth is coarse sand with 0 percent clay; single grain; loose, nonsticky and nonplastic; common course and few medium irregularly shaped pores; 95 percent gravel; secondary calcium sulfate segregated as few coarse irregular shaped accumulations on the undersides of rock fragments; slightly effervescent, secondary calcium carbonate segregated as few medium and coarse irregularly shaped accumulations on rock fragments; strongly alkaline (pH 8.6).
TYPE LOCATION: Santa Fe County, New Mexico; about 7 miles west of Agua Fria; about 1,700 feet west and 350 feet south of the northwest corner of section 1, T.16N., R.7E.; USGS Montoso Peak 7.5 minute topographic quadrangle; Latitude 35 degrees 39 minutes 7 seconds North and Longitude 106 degrees 8 minutes 47 seconds West.
RANGE IN CHARACTERISTICS:
Soil moisture - The soil moisture control section is intermittently moist in some part from July to October and December to March. It is assumed to be dry in all parts 50 to 75 percent of the time (cumulative), when the soil temperature at 20 inches is 41 degrees F. or higher. 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.
Thickness of mollic epipedon - 7 to 9 inches
Depth to base of argillic horizon 10 to 20 inches
Depth to calcareous material (as visible secondary calcium carbonate) - 6 to 12 inches
Depth to duripan - 10 to 18 inches
Lithology or rock fragments mostly cinders
Particle-size control section (weighted averages)
Silicate clay content: 25 to 35 percent
Sand content: 35 to 50 percent
Fine sand and coarser content: 25 to 35 percent
Rock fragment content: 35 to 50 percent
A horizon
Hue: 5YR or 7.5YR
Value: 4 or 5 dry, 2.5 or 3 moist
Chroma: 2 or 3, dry or moist
Rock fragment content: total range is 60 to 75 percent
50 to 60 percent gravel
10 to 20 percent cobbles
1 to 3 percent stones
Bt horizons
Hue: 5YR or 7.5YR
Value: 4 or 5 dry, 2.5 or 3 moist
Chroma: 2 to 4, dry or moist
Texture: very gravelly loam or very gravelly clay loam
Clay content: 25 to 35 percent
Rock fragment content: total range is 35 to 60 percent
30 to 50 percent gravel
0 to 10 percent cobbles
Reaction: slightly alkaline or moderately alkaline
Btk horizon (a calcic horizon in some pedons)
Hue: 5YR or 7.5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 or 4, dry or moist
Texture: very gravelly clay loam or very gravelly loam
Clay content: 25 to 35 percent
Rock fragment content: total range is 35 to 60 percent
35 to 50 percent gravel
0 to 10 percent cobbles
Calcium carbonate equivalent: 12 to 30 percent
Sodicity, SAR: 0 to 4
Reaction: moderately alkaline or strongly alkaline
Where this horizon is thick enough to qualify for a calcic horizon, the calcium carbonate equivalent is usually too low.
Bk horizon (a calcic horizon in some pedons)
Hue: 5YR or 7.5YR
Value: 6 to 8 dry, 5 or 6 moist
Chroma: 2 to 4, dry or moist
Texture: gravelly loam or very gravelly loam
Clay content: 15 to 25 percent
Rock fragment content: total range is 20 to 60 percent
15 to 50 percent gravel
0 to 10 percent cobbles
Calcium carbonate equivalent: 30 to 75 percent
Sodicity, SAR: 0 to 4
Reaction: moderately alkaline or strongly alkaline
Bkqm horizon
Hue: 5YR or 7.5YR
Value: 7 or 8 dry, 6 or 7 moist
Chroma: 1 to 4 dry or moist
Reaction: moderately alkaline or strongly alkaline
2BCky horizons
Hue: 2.5YR, 5YR or 7.5YR
Value: 4 or 5 dry, 3 or 4 moist
Chroma: 3 to 6 dry or moist
Cinder content: 90 to 95 percent, mostly gravel sized
Calcium carbonate equivalent: 0 to 5 percent
Reaction: moderately alkaline or strongly alkaline
COMPETING SERIES: At present, there are no other series in this family.
GEOGRAPHIC SETTING: Medrano soils are on backslopes of cinder cones. They formed in slope alluvium over residuum weathered from scoria (cinders). Slopes are 5 to 65 percent. Elevation ranges from 5,700 to 6,900 feet. The mean annual precipitation is 10 to 13 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 Calabasas, Churipa, Tetilla, and Tsinat soils. Calabasas soils are deep to petrocalcic horizons, are fine-silty, and occur on summits of undulating plateaus. Churipa soils are shallow to duripans and moderately deep to basalt, are loamy, and occur on beveled summits and shoulders of undulating plateaus. Tetilla soils have calcic horizons below 40 inches, do not have cemented pans, and occur on toeslopes of undulating plateaus. Tsinat soils are moderately deep to petrocalcic horizons, have calcic horizons, and occur on beveled summits of plateaus.
DRAINAGE AND PERMEABILITY: Well drained; rapid surface runoff; moderately slow permeability in the subsoil, very slow permeability in the duripan horizon, and very rapid permeability in the substratum.
USE AND VEGETATION: Medrano soils are used for urban development, livestock grazing, and recreation. The historic climax vegetation is blue grama, galleta, sideoats grama, black grama, New Mexico feathergrass, oneseed juniper, and twoneedle pinyon. The ecological site is Gravelly(R036XB114NM).
DISTRIBUTION AND EXTENT: Medrano soils are of small extent on the southcentral 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. Medrano is a Spanish surname.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from 0 to 2 inches (A horizon)
Argillic horizon - The zone from 2 to 18 inches (Bt1, Bt2, and Btk horizons)
Duripan - The zone from 18 to 24 inches (Bkqm horizon)
Particle-size control section from 2 to 18 inches (the entire argillic horizon)
Classified according to Keys to Soil Taxonomy Tenth Edition, 2006.