LOCATION LADRON NMEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, carbonatic, mesic Ustic Haplocalcids
TYPICAL PEDON: Ladron very gravelly sandy loam--on a 14 percent convex south facing slopes--rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 2 inches; pale brown (10YR 6/3) very gravelly sandy loam, brown (10YR 4/3) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; few very fine roots; 40 percent gravel and 10 percent cobbles; strongly effervescent with disseminated calcium carbonates; slightly alkaline; abrupt wavy boundary. (2 to 4 inches thick)
Bw--2 to 9 inches; light yellowish brown (10YR 6/4) very gravelly loam, dark yellowish brown (10YR 4/4) moist; weak fine and very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; 50 percent gravel and 5 percent cobbles; strongly effervescent with disseminated calcium carbonates; slightly alkaline; gradual wavy boundary. (6 to 12 inches thick)
Bk1--9 to 19 inches; very pale brown (10YR 8/3) very gravelly loam, very pale brown (10YR 7/3) moist; weak fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common fine and few very fine roots; 35 percent gravel and 10 percent cobbles; violently effervescent; calcium carbonates disseminated and segregated in few fine soft masses and as coatings on rock fragments; moderately alkaline; clear wavy boundary. (8 to 12 inches thick)
Bk2--19 to 31 inches; very pale brown (10YR 7/4) very gravelly loam, light yellowish brown (10YR 6/4) moist; weak very fine subangular blocky structure; slightly hard, friable, nonsticky and slightly plastic; common medium and few very fine roots; 40 percent gravel and 10 percent cobbles; violently effervescent; calcium carbonates disseminated and segregated in few fine soft masses and as coatings on rock fragments; slightly alkaline; abrupt smooth boundary. (8 to 14 inches thick)
2Bk3--31 to 39 inches; very pale brown (10YR 7/4) very gravelly sandy loam, light yellowish brown (10YR 6/4) moist; weak fine subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; few very fine roots; 40 percent gravel and 5 percent cobbles; violently effervescent; calcium carbonates disseminated and as pendants on the undersides of rock fragments; moderately alkaline; clear smooth boundary. (7 to 12 inches thick)
2Bk4--39 to 47 inches; very pale brown (10YR 7/3) very gravelly sandy loam, pale brown (10YR 6/3) moist; weak moderate and fine subangular blocky structure; hard, firm, nonsticky and nonplastic; few common and fine roots; 40 percent gravel and 5 percent cobbles; violently effervescent; calcium carbonates disseminated and as coatings on rock fragments; moderately alkaline; clear wavy boundary. (8 to 18 inches thick)
3Bkb--47 to 60 inches; very pale brown (10YR 7/3) very gravelly loam; pale brown (10YR 6/3) moist; weak coarse subangular blocky structure; hard, firm, nonsticky and slightly plastic; 50 percent gravel and 5 percent cobbles; strongly effervescent; calcium carbonates disseminated and as coatings on rock fragments; strongly alkaline.
TYPE LOCATION: Socorro County, New Mexico; 33 miles northwest of Socorro; 1,950 feet south and 350 feet west of the NE corner of section 15, T. 2 N., R. 3 W.
RANGE IN CHARACTERISTICS:
Soil moisture: some part of the soil moisture control section is moist during December and January and the soil moisture control section is moist in some part periodically during July, August and September after convective storms. Driest during May and June. Ustic aridic moisture regime.
Depth to the calcic horizon: 8 to 16 inches
Mineralogy class: carbonatic-10 to 40-inch control section averages greater than 40 percent carbonate by weight in the fine earth fraction.
Rock fragments in particle-size control section: averages 35 to 60 percent by volume
Depth to the 2Bk horizon: 26 to 36 inches
A horizon
Hue: 7.5YR or 10YR
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 3 through 6
Rock fragment content: 35 to 60 percent by volume
Bk or Bw (if present) horizon
Hue: 7.5YR or 10YR
Value: 5 through 8 dry, 4 through 7 moist
Chroma: 2 through 4
Clay content: 18 to 26 percent
Rock fragments (by volume): 5 to 10 percent cobbles, 30 to 50 percent gravel
2Bk horizon
Hue: 7.5YR or 10YR
Value: 7 or 8 dry
Chroma: 3 or 4
Fine-earth fraction: sandy loam or loam
Rock fragments: 0 to 10 percent cobbles, 35 to 50 percent gravel
Clay content: 8 to 15 percent
3Bkb horizon
Hue: 7.5YR or 10YR
Chroma: 3 or 4
Fine-earth fraction: sandy loam or loam
Rock fragments (by volume): 0 to 5 percent cobbles, 35 to 55 percent gravel
Clay content: 18 to 25 percent
COMPETING SERIES: These are the Ildecarb (NM), Moab (UT), Puice (NM), Socorro (NM), Stormitt (UT), Storsun (WY), and Tusayan (AZ) series. Ildecarb, Moab, Stormitt, and Storsun soils lack a lithologic discontinuity at depths less than 40 inches. Ildecarb soils also have 5 to 15 percent gypsum. Puice, Socorro and Tusayan soils have bedrock between depths of 20 and 40 inches. In addition, Ildecarb, Puice, Socorro, and Storsun soils are in the Western Great Plains (LRR-G) and are more moist in May and June.
GEOGRAPHIC SETTING: Ladron soils are on knolls, ridges and fan terraces and have slopes ranging from 1 to 15 percent. The soils formed in alluvium. Elevations range from 5,500 to 7,000 feet. Average annual precipitation ranges from 10 to 13 inches. Average annual temperature ranges from 49 to 57 degrees F., and the average frost-free period is 150 to 170 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cascajo, Clovis, Harvey and Lapdun soils. Cascajo soils are sandy-skeletal. Clovis soils have an argillic horizon. Harvey soils have less than 15 percent coarse fragments. Lapdun soils have a mollic epipedon.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: The major use of this soil is for livestock grazing. Native vegetation is black grama, blue grama, New Mexico feathergrass, winterfat, walkingstick cholla and oneseed juniper.
DISTRIBUTION AND EXTENT: South-central, New Mexico. Ladron soils are of moderate extent. MLRA 35.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Socorro County, New Mexico, 1984.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Calcic horizon - the zone from about 9 to 31 inches. (Bkl, Bk2 horizons)
Lithologic feature - the occurrence of lithologic discontinuity at about 31 inches.
Classified according to Soil Taxonomy Second Edition, 1999.
ADDITIONAL DATA: Calcium carbonate equivalent determined by use of a volumetric calcimeter.