LOCATION OWLROCK NMEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Lithic Argiustolls
TYPICAL PEDON: Owlrock very gravelly loam--in a ponderosa pine forestland on an east facing, convex surface of 2 percent slope at an elevation of 7,720 feet. (Colors are for dry soils unless otherwise noted.) The surface is covered with 40 percent gravel, 10 percent cobbles, and 5 percent stones (all fragments are limestone).
A--0 to 1 inch; grayish brown (10YR 5/2) very gravelly loam, very dark grayish brown (10YR 3/2) moist; weak very fine granular structure; soft, very friable, slightly sticky and nonplastic; many very fine and fine roots; few very fine irregular pores; 40 percent gravel, 10 percent cobbles, 5 percent stones; strongly effervescent; 14 percent calcium carbonate equivalent; moderately alkaline (8.2); abrupt smooth boundary. (1 to 4 inches thick)
Btk1--1 to 6 inches; grayish brown (10YR 5/2) very cobbly loam, very dark grayish brown (10YR 3/2) moist; weak very fine and fine subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; common very fine, fine, and few medium roots; few very fine irregular pores; few distinct clay films on faces of peds; 10 percent gravel, 50 percent cobbles, 5 percent stones; slightly effervescent; few very fine and fine concretions and masses of calcium carbonate; 10 percent calcium carbonate equivalent; moderately alkaline (8.0); abrupt smooth boundary. (5 to 12 inches thick)
Btk2--6 to 13 inches; brown (7.5YR 5/2) very cobbly loam, dark brown (7.5YR 3/2) moist; weak very fine and fine subangular blocky structure; soft, very friable, slightly sticky and nonplastic; few very fine, fine, and medium roots; 10 percent gravel, 50 percent cobbles, 5 percent stones; strongly effervescent; common very fine and fine concretions of calcium carbonate; 14 percent calcium carbonate equivalent; moderately alkaline (8.0); abrupt smooth boundary. (0 to 7 inches thick)
R--13 inches; San Andreas limestone
TYPE LOCATION: McKinley County, New Mexico; Upper Nutria Quadrangle; about 2200 feet east and 1,250 feet south of the northwest corner of section 22, T. 13 N., R. 16 W.; 108 degrees 31 minutes 18 seconds west longitude, 35 degrees 20 minutes 51 seconds north latitude.
RANGE IN CHARACTERISTICS:
Soil Moisture: The SMCS is usually moist, in some part, for more than 90 cumulative days from May through October. It is usually dry, in all parts, for less than 90 cumulative days during the same period. It is continuously moist in some part November through April. The period of maximum precipitation is July through October. The soil is driest during May and June. Typic ustic moisture regime.
Soil Temperature: 42 to 47 degrees F
Particle size control section: 15 to 30 percent clay and 35 to 75 percent limestone gravel, cobbles, and stones
Mollic epipedon: 4 to 15 inches thick
Depth to lithic contact: 7 to 20 inches to dolomitic limestone
Calcium carbonate equivalent: 5 to 15 percent.
Reaction: slightly to moderately alkaline
A horizon
Hue: 5YR to 10YR
Value: 4 or 5 dry
Chroma: 2 or 3
Rock fragments: 50 to 80 percent total limestone fragments; 35 to 40 percent gravel, 10 to 40 percent cobbles, 0 to 5 percent stones
Calcium carbonate equivalent: 5 to 15 percent
Btk1 horizon
Hue: 5YR to 10YR
Value: 4 or 5 dry
Chroma: 2 through 4
Rock fragments: 35 to 75 percent total limestone fragments; 5 to 10 percent gravel, 25 to 50 percent cobbles, and 5 to 10 percent stones
Calcium carbonate equivalent: 5 to 15 percent
Btk2 horizon
Hue: 5YR or 7.5YR
Value: 4 or 5 dry
Chroma: 2 or 3
Textures: Loam or clay loam
Rock fragments: 35 to 75 percent limestone fragments; 5 to 10 percent gravel, 25 to 50 percent cobbles, and 5 to 10 percent stones
Calcium carbonate equivalent: 5 to 15 percent
Some pedons have Bk horizons on top of the lithic contact.
COMPETING SERIES: Current competitors are the Agrirocker (SD), Bushvalley (AZ), Gnojek (MT), Teaspoon (CO), Tolbert (MT), Tolman (WY) and Zibetod (AZ) series. Agrirocker soils are moist in May and June. Bushvalley soils are shallow to tuff. The Gnojek, Tolman and Zibetod soils are shallow to sandstone. The Teaspoon soils are shallow to gneiss. The Tolbert soils are shallow to granite. Zibetod soils average less than 18 percent clay.
GEOGRAPHIC SETTING: The Owlrock soils formed in residuum derived from dolomitic limestone of the San Andreas formation and are on dipslopes of cuestas and summits and shoulders of ridges. Slopes are 2 to 8 percent. Elevations range from 7,200 to 8,200 feet. The mean annual temperature is 40 to 45 degrees F., and the mean annual precipitation is 16 to 20 inches. The frost free period is 90 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Losegate, Osoridge, Polich, and the Asaayi series. The Losegate soils are moderately deep and are on dipslopes of cuestas. The Osoridge soils are fine textured, shallow to sandstone and are on summits of ridges. The Polich soils are very deep and are on valley floors. The Asaayi soils are shallow and on cuestas and ridges.
DRAINAGE AND PERMEABILITY: Well drained, medium to high runoff, and moderate permeability.
USE AND VEGETATION: This series is used for wood products, limited livestock grazing and wildlife habitat. The present vegetation is ponderosa pine with an understory of Gambel oak, muttongrass, blue grama, Arizona fescue, and bottlebrush squirreltail.
DISTRIBUTION AND EXTENT: West central, New Mexico; MLRA 39, 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:
Mollic epipedon: The zone from the surface to a depth of 13 inches. (A, Btk1, and Btk2 horizons)
Argillic horizon: The zone from 1 to 6 inches. (Btk1 and Btk2 horizons)
Lithic contact: Dolomitic limestone bedrock at 13 inches. (R horizon)
Percent rock fragments were determined by weight and calcium carbonate equivalent was determined by the gas volumetric method, both by the survey field lab.
Classified according to Soil Taxonomy Second Edition, 1999.