LOCATION REDPEN NMEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Ustic Haplargids
TYPICAL PEDON: Redpen sandy clay loam--in an abandoned cropland field on a 2 percent south facing slope at an elevation of 6,330 feet. (Colors are for dry soils unless otherwise noted.)
Ap--0 to 4 inches; reddish brown (2.5YR 4/4) sandy clay loam, dark reddish brown (2.5YR 3/4) moist; weak fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; many very fine irregular pores; violently effervescent; slightly alkaline (pH 7.6); clear smooth boundary. (2 to 5 inches thick)
Bt--4 to 15 inches; reddish brown (2.5YR 4/4) sandy clay loam, dark reddish brown (2.5YR 3/4) moist; moderate medium and coarse prismatic structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; common fine irregular pores; many prominent clay films bridging sand grains; violently effervescent; few fine irregular soft filaments of calcium carbonate; slightly alkaline (pH 7.6); clear smooth boundary. (The combined thickness of the Bt horizons is 11 to 24 inches.)
Btk--15 to 24 inches; reddish brown (2.5YR 4/4) sandy clay loam, dark reddish brown (2.5YR 3/4) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common fine irregular pores; common prominent clay films bridging sand grains; violently effervescent; many medium irregular soft filaments of calcium carbonate; moderately alkaline (pH 8.4); clear smooth boundary. (The combined thickness of the Bt horizons is 11 to 24 inches.)
Bk1--24 to 52 inches; reddish brown (2.5YR 4/4) sandy clay loam, dark reddish brown (2.5YR 3/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; common fine irregular pores; violently effervescent; many medium irregular soft masses of calcium carbonate; moderately alkaline (pH 8.4); clear smooth boundary. (The combined thickness of the Bk horizons is 0 to 47 inches.)
Bk2--52 to 65 inches; reddish brown (2.5YR 4/4) clay loam, dark reddish brown (2.5YR 3/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; common fine irregular pores; violently effervescent; few fine irregular soft filaments of calcium carbonate; moderately alkaline (pH 8.4). (The combined thickness of the Bk horizons is 0 to 47 inches.)
TYPE LOCATION: McKinley County, New Mexico; Zuni Quadrangle; about 1. 7 miles north of Zuni Pueblo; 108 degrees 51 minutes 7 seconds west longitude, 35 degrees 5 minutes 33 seconds north latitude.
RANGE IN CHARACTERISTICS:
Soil Moisture: The SMCS is usually dry, in all parts, 105 to 160 cumulative days from April through October. It is usually moist, in some part, 50 to 105 cumulative days during the same period. It is intermittently moist in some part November through April. The period of maximum precipitation is July through October. The soil is driest during May and June. Ustic aridic moisture regime.
Soil Temperature: 51 to 56 degrees F
Particle-size control section: 27 to 35 percent clay and greater than 40 percent sand
Reaction: slightly or moderately alkaline
Percent calcium carbonate equivalent: 5 to 10 percent, calcareous in all parts
Ap or A horizon:
Hue: 2.5YR or 5YR
Value: 3 or 4 moist
Chroma: 4 or 6 moist
Rock fragments: 0 to 5 percent gravel
Bt or Btk horizon:
Value: 3 or 4 moist
Chroma: 4 or 6 moist
Texture: sandy clay loam or clay loam
Rock fragments: 0 to 10 percent sandstone gravel
Bk horizon:
Value: 3 or 4
Chroma: 4 or 6 moist
Texture: sandy clay loam or clay loam
Rock fragments: 0 to 10 percent sandstone gravel
Some pedons have highly stratified, calcareous, silt loam, fine sandy loam, clay loam and sandy clay loam C horizons.
COMPETING SERIES: These are the Balon (AZ), Blancot (NM), Bowbac (WY), Buckle (NM), Cambria (WY), Cerropelon (NM), Chilerojo (NM), Cumacho (NM), Cushman (WY), Decolney (WY), Doakum (NM), Forkwood (WY), Fort (CO)(T), Gaddes (AZ), Gapbutte (AZ), Gapmesa (CO), Hagerman (NM), Hagerwest (NM), Hiland (WY), Mentmore (NM), Oelop (NM), Olney (CO), Palacid (NM), Penistaja (NM), Pokeman (WY), Potts (WY), Pugsley (WY), Quagwa (AZ), Spangler (WY), Sundance (CO), Tamarindo (NM)(T), Teckla (WY), and Yenlo (CO) series. Balon and Decolney soils are noncalcareous throughout. Penistaja soils are not calcareous in all parts. Bowbac, Cerropelon, Cushman, Gaddes, Gapbutte, Gapmesa, Hagerman, Pokeman, Pugsley and Spangler soils have lithic or paralithic contacts at depths between 20 and 40 inches. Buckle, Harbord, Oelop, Palacid and Quagwa soils have less than 40 percent sand in the particle-size control section. Blancot, Doakum, Fort, Mentmore, and Yenlo soils typically have hue yellower than 7.5YR in the Bt horizon. Chilerojo soils are very deep to a densic horizon. Cumacho soils are deep to a paralithic contact. Sundance soils have buried paleosol horizons. Teckla soils contain 35 to 70 percent porcelanite rock fragments below a 20 to 40 inch depth. In addition, the Bowbac, Cambria, Cushman, Decolney, Forkwood, Fort, Hagerman, Hiland, Olney, Pokeman, Potts, Pugsley, Spangler, Sundance, Tekla and Yenlo series are in LRR-G and are more moist in May and June.
GEOGRAPHIC SETTING: The Redpen soils formed in eolian and alluvium and fan alluvium derived from sandstone and shale of the Glen Canyon Group undivided and Chinle formations. Redpen soils are on fan remnants on valley sides. Slopes are 0 to 2 percent. Elevations range from 6,000 to 6,500 feet. The mean annual temperature is 49 to 54 degrees F., and the mean annual precipitation is 10 to 13 inches. The frost free period is 120 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aparejo, Aquima, Mido, Padilla, the proposed Tintero, and Zia soils and the competing Penistaja series. The Aparejo soils lack an argillic horizon and occur on flood plains. The Mido soils lack an argillic horizon, are sandy throughout, and occur on dunes. The Padilla soils have more than 35 percent clay in the particle-size control section. The Tintero and Zia soils have less than 18 percent clay in the particle-size control section and have hues more yellow than 2.5YR.
DRAINAGE AND PERMEABILITY: Well drained, low runoff, and moderately slow permeability.
USE AND VEGETATION: Redpen soils are used for irrigated crops, mainly alfalfa, corn, small grains and pasture. They are also used for livestock grazing. Principal native vegetation is blue grama, western wheatgrass, Indian ricegrass, sand dropseed, fourwing saltbush, winterfat and scattered one-seed juniper.
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 the surface to a depth of 4 inches. (Ap horizon)
Argillic horizon - the zone from 4 to 24 inches. (Bt and Btk horizons)
Classified according to Soil Taxonomy Second Edition, 1999.