LOCATION DEAN NM+AZ+UTEstablished Series
TAXONOMIC CLASS: Fine-loamy, carbonatic, mesic Ustic Haplocalcids
TYPICAL PEDON: Dean gravelly fine sandy loam - on a south-facing slope of 4 percent at 6,200 feet elevation - rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 4 inches; light brown (7.5YR 6/4) gravelly fine sandy loam, brown (7.5YR 5/4) moist; weak thin platy and weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; few fine and very fine roots; few very fine vesicular pores; 20 percent limestone gravel; violently effervescent; moderately alkaline; clear wavy boundary. (2 to 8 inches thick)
Bw--4 to 18 inches; light brown (7.5YR 6/4) gravelly sandy clay loam, brown (7.5YR 5/4) moist; weak coarse subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few fine and common very fine roots; few fine and very fine tubular pores; 20 percent limestone gravel; violently effervescent; moderately alkaline; clear wavy boundary. (0 to 14 inches thick)
Bk1--18 to 38 inches; pinkish white (7.5YR 8/2) gravelly loam, pink (7.5YR 7/4) moist; moderate thick platy structure; hard, firm, sticky and slightly plastic; few fine and very fine roots; few very fine interstitial pores; 25 percent limestone gravel; violently effervescent; carbonates coating gravel; weak continuous cementation caused by secondary carbonates; moderately alkaline; clear wavy boundary.
Bk2--38 to 52 inches; pinkish white (7.5YR 8/2) gravelly loam, pink (7.5YR 7/4) moist; moderate coarse subangular blocky structure; very hard, very firm, sticky and plastic; few fine and very fine roots; few very fine interstitial pores; 25 percent limestone gravel; violently effervescent; carbonates completely coating gravel; weak continuous cementation caused by secondary carbonates; moderately alkaline; clear wavy boundary.
Bk3--52 to 58 inches; pink (7.5YR 7/4) gravelly loam, reddish yellow (7.5YR 6/6) moist; weak coarse and moderate medium subangular blocky structure; hard, friable, sticky and slightly plastic; few fine and very fine roots; common very fine interstitial and tubular pores; 20 percent limestone gravel; violently effervescent, secondary carbonates segregated in few fine seams and threads; moderately alkaline (pH 8.4) clear wavy boundary. (Combined thickness of Bk horizons is 25 to 60 inches)
2C--58 to 70 inches; light brown (7.5YR 6/4) sandy clay loam, strong brown (7.5YR 5/6) moist; dominantly massive with some pockets of weak coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few fine and very fine roots; common very fine interstitial and tubular pores; 10 percent limestone gravel; strongly effervescent; moderately alkaline (pH 8.2).
TYPE LOCATION: Socorro County, New Mexico; about 3 miles southwest of Claunch and 3,850 feet north and 250 feet east of the southwest quarter, sec. 19, T. 2 S., R. 9 E.
RANGE IN CHARACTERISTICS:
Soil Moisture: Typically, some parts of the soil moisture control section are intermittently moist from July to September following convective storms.
Soil Temperature: 47 to 59 degrees F.
Depth to calcic horizon ranges from 5 to 20 inches
Percent calcium carbonate equivalence in the mineralogy control section ranges from 40 to 80 percent. In some pedons the weak cementation is discontinuous. Below a depth of about 36 to 52 inches, secondary carbonates decrease markedly with depth. In some pedons, the 2C horizon does not occur.
Percent gypsum in the mineralogy control section is estimated to range from 0 to 5 percent.
Rock fragments are dominantly limestone or indurated carbonate gravel. In some pedons the rock fragments are mixed and may be granite, quartzite, sandstone or siltstone. In the 10 to 40 inch control section the weighted average of rock fragments is typically 15 to 35 percent. In some pedons, i.e. Utah, the weighted average is between 10 to 15 percent.
Profile reaction: slightly to strongly alkaline and calcareous throughout.
Percent clay in control section: 18 to 35
Percent fine sand or coarser: more than 15
In some pedons limestone bedrock may occur between 42 and 60 inches.
A horizon
Hue: 7.5YR or 10YR
Value: 3 to 7 dry, 3 to 5 moist
Chroma: 2 to 5
Texture (fine earth fraction): fine sandy loam or loam
Bw horizon (where present)
Hue: 7.5YR or 10YR
Value: 5 to 7 dry, 4 or 5 moist
Chroma: 2 to 4
Texture (fine earth fraction): fine sandy loam, sandy loam, loam, or sandy clay loam
Bk horizons
Hue: 5YR, 7.5YR or 10YR
Value: 5 to 8 dry, 4 to 8 moist
Chroma: 2 to 6
Texture (fine earth fraction): loam, sandy loam, or sandy clay loam
2C horizon (where present)
Hue: 7.5YR or 10YR
Value: 6 or 7 dry, 5 or 6 moist
Chroma: 2 to 6
Texture (fine earth fraction): loam, sandy loam, sandy clay loam or clay loam
COMPETING SERIES: These are the Chew (UT) and Singerton (CO) series. Chew soils have a lithic contact with limestone between 20 and 40 inches. Singerton soils do not have weak cementation and have less than 15 percent rock fragments in the control section.
GEOGRAPHIC SETTING: Dean soils are on bajadas, ridges, mesas, and fan terraces. Dean soils formed in alluvium derived dominantly from limestone, but also may contain material derived from granite, quartzite, gypsum rock, sandstone or eolian sand deposits. Slopes range from 0 to 20 percent but range to 40 percent in Utah. Mean annual precipitation ranges from 10 to 13 inches, but ranges to 16 inches in some areas. Mean annual temperature ranges from 46 to 58 degrees F. The average frost-free period is typically 130 to 180 days, but ranges to 110 days in Utah. Elevation ranges from 4,500 to 7,200 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Gabaldon, Harvey, La Fonda, Pinon, Puice, and Tanbark soils. Gabaldon soils are in swales and have a fine-silty control section. Harvey and La Fonda soils do not have carbonatic mineralogy. Puice soils have greater than 35 percent rock fragments in the control section and are moderately deep to limestone bedrock. Tanbark soils have gypsic mineralogy and are shallow to gypsum bedrock.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate. Runoff is negligible on slopes less than 1 percent, very low on 3 to 5 percent slopes, low on 3 to 5 percent slopes, medium on 5 to 20 percent slopes, and high on slopes greater than 20 percent.
USE AND VEGETATION: Dean soils are used for livestock grazing. Present vegetation is blue grama, black grama, winterfat, Bigelow sagebrush, soapweed yucca, walkingstick cholla, and scattered oneseed juniper.
DISTRIBUTION AND EXTENT: Dean soils are extensive. MLRA 70, 77, 36 and 35.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Valencia County, New Mexico, 1970.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 4 inches. (A horizon). The epipedon contains less than 40 percent calcium carbonate equivalent and when colors meet the requirements of a mollic epipedon, the horizon is too thin.
Calcic horizon - 18 inches to 52 inches. (Bk1, Bk2 horizons).
Taxonomic version: Keys to Soil Taxonomy Ninth edition, 2003