LOCATION SHADILTO NMEstablished Series
TAXONOMIC CLASS: Loamy, carbonatic, mesic Lithic Calciustepts
TYPICAL PEDON: Shadilto very gravelly sandy loam--in rangeland on a 5 percent north facing slope at an elevation of 7,500 feet. (Colors are for dry soils unless otherwise noted.)
A--0 to 1 inch; brown (7.5YR 5/4) very gravelly sandy loam, brown (7.5YR 4/4) moist; weak thin platy structure; soft, very friable, nonsticky and nonplastic; many fine and common medium roots; many fine vesicular pores; calcium carbonate is disseminated and segregated in few fine masses; strongly effervescent (25 percent calcium carbonate equivalent); 50 percent limestone gravel and 5 percent cobbles; moderately alkaline (pH 8.0); clear smooth boundary. (1 to 3 inches thick)
Bk1--1 to 9 inches; brown (7.5YR 5/4) sandy loam, brown (7.5YR 4/4) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many fine and few medium roots; common fine irregular pores; common fine and medium calcium carbonate concretions; calcium carbonate is disseminated and segregated in many very fine masses and coating rock fragments; violently effervescent (70 percent calcium carbonate equivalent); 10 percent limestone gravel; moderately alkaline (pH 8.2); clear smooth boundary.
Bk2--9 to 13 inches; pinkish gray (7.5YR 6/2) sandy loam, brown (7.5YR 5/3) moist; weak fine and medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common fine and few medium and coarse roots; common fine irregular pores; many fine calcium carbonate concretions; calcium carbonate is disseminated and segregated in many fine masses and coating rock fragments; violently effervescent (75 percent calcium carbonate equivalent); 5 percent limestone gravel and 5 percent cobbles; moderately alkaline (pH 8.2); clear smooth boundary.
Bk3--13 to 15 inches; pinkish white (7.5YR 8/2) sandy loam, pink (7.5YR 7/3) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few fine and medium roots; few fine irregular pores; many fine calcium carbonate concretions; calcium carbonate is disseminated and segregated in many fine masses and coating rock fragments; violently effervescent (80 percent calcium carbonate equivalent); 5 percent limestone gravel and 2 percent cobbles; moderately alkaline (pH 8.2); abrupt smooth boundary. (The combined thickness of the Bk horizon is 6 to 19 inches.)
R--15 inches; limestone.
TYPE LOCATION: McKinley County, New Mexico; Thoreau Quadrangle; about 3.3 miles northeast of Thoreau, New Mexico; 108 degrees 10 minutes 38 seconds west longitude, 35 degrees 26 minutes 1 seconds north latitude.
RANGE IN CHARACTERISTICS:
Soil Moisture: The SMCS is usually moist, in all parts, for less than 90 cumulative days from April through October. It is usually dry, in some part, for more than 120 cumulative days during the same period. It is continuously moist in some part November through March. The period of maximum precipitation is July through October. The soil is driest during May and June. Aridic ustic moisture regime.
Soil Temperature: 50 to 55 degrees F
Depth to calcic horizon: 1 to 3 inches
Depth to lithic contact: 6 to 20 inches to limestone
Particle size control section: 8 to 18 percent clay and greater than 55 percent sand
A horizon:
Hue: 5YR, 7.5YR, or 10YR
Value: 3 or 4 moist
Chroma: 3 or 4 moist
Rock fragments: 35 to 60 percent total (mostly limestone with some sandstone)
35 to 60 percent gravel
0 to 10 percent cobbles
Calcium carbonate equivalent: 10 to 40 percent
Bk horizon:
Hue: 7.5YR or 10YR
Value: 5 to 8 dry, 3 to 7 moist
Chroma: 2 to 4 dry, 3 or 4 moist
Rock fragments: 5 to 35 percent total (limestone)
5 to 20 percent gravel
0 to 30 percent cobbles
Calcium carbonate equivalent: 40 to 80 percent
COMPETING SERIES: There are no competitors.
GEOGRAPHIC SETTING: The Shadilto soils formed in eolian material over residuum derived from sandstone and limestone (Todilto formation) and are on dip slopes of cuestas. Slopes are 2 to 8 percent. Elevations range from 7,000 to 7,700 feet. The mean annual temperature is 48 to 53 degrees F., and the mean annual precipitation is 13 to 16 inches. The frost free period is 115 to 135 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Westion and Todest soils. Westion soils are clayey and shallow to shale. The Todest soils have an argillic horizon and are moderately deep.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained, low to high runoff, and moderately rapid permeability.
USE AND VEGETATION: This series is used for livestock grazing. The present vegetation is scattered pinyon and oneseed juniper, mountain mahogany, cliffrose, Bigelow sage, blue grama, threeawns, and New Mexico feathergrass.
DISTRIBUTION AND EXTENT: West central New Mexico. MLRA 35, LRR-D. This series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: McKinley County Area, New Mexico; McKinley County and Parts of Cibola and San Juan Counties, 2001.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: The zone from 0 to 1 inch. (A horizon)
Calcic horizon: The zone from 1 to 15 inches. (Bk1, Bk2, and Bk3 horizons)
Lithic contact: Limestone contact at 15 inches. (R horizon)
Carbonatic feature: The PSCS has greater that 40 percent calcium carbonate equivalent. Calcium carbonate equivalents determined with field calcimeters.
Classified according to Soil Taxonomy Second Edition, 1999.