LOCATION ZUNI NMEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, frigid Typic Haplustalfs
TYPICAL PEDON: Zuni gravelly sandy loam-in a ponderosa pine woodland on a convex surface of 4 percent slope at an elevation of 8,130 feet. (Colors are for dry soils unless otherwise noted.)
Oi--0 to 1 inches: Slightly decomposed pine needles
A--1 to 3 inches; brown (7.5YR 5/2) gravelly sandy loam, brown (7.5YR 4/2) moist; weak very fine granular structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; few very fine irregular pores; 30 percent gravel and 1 percent cobble size gneissic-granite fragments; neutral (pH 6.8); abrupt wavy boundary. (1 to 5 inches thick)
Bt1--3 to 18 inches; red (2.5YR 5/6) gravelly sandy clay, red (2.5YR 4/6) moist; strong fine subangular blocky structure; very hard, very firm, sticky and plastic; common fine and few moderate and coarse roots; few very fine irregular pores; many distinct clay films on faces of peds; 30 percent gravel and 1 percent cobble sized gneissic-granite fragments; neutral (pH 6.8); clear wavy boundary.
Bt2--18 to 27 inches; red (2.5YR 5/6) gravelly sandy clay, red (2.5YR 4/6) moist; strong very fine and fine subangular blocky structure; very hard, very firm, sticky and plastic; common very fine, fine, and few medium roots; few very fine irregular pores; common distinct clay films on faces of peds; 28 percent gravel size gneissic-granite fragments; neutral (pH 7.2); abrupt wavy boundary. (The combined thickness of the Bt horizons is 17 to 34 inches)
R--27 inches; Gneissic-granite
TYPE LOCATION: McKinley County, New Mexico; about 300 feet east of the McGaffey lookout tower; Upper Nutria Quadrangle; 900 feet east and 300 feet south of the northwest corner of section 14, T.13N., R. 16W.; 108 degrees 30 minutes 28 seconds west longitude and 35 degrees 21 minutes 49 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: 35 to 50 percent clay
Depth to a lithic contact: 20 to 40 inches to gneissic-granite
Rock fragments: control section weighted average is 25 to 35 percent gravel size gneissic-granite fragments
Reaction: slightly acid to neutral
A horizon:
Hue: 5YR to 10YR
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 2
Textures: sandy loam or sandy clay loam
Rock fragments: 5 to 35 percent total; 5 to 35 percent gravel, 0 to 2 percent cobbles (gneissic-granite fragments)
Bt horizons:
Hue: 2.5YR to 7.5YR
Value: 4 to 6 dry, 4 moist
Chroma: 4 or 6
Textures: sandy clay or sandy clay loam
Rock fragments: 25 to 35 percent total; 25 to 35 percent gravel, 0 to 2 percent cobbles (gneissic-granite fragments)
Some pedons have E horizons that range in thickness from 5 to 12 inches.
COMPETING SERIES: These are the Crow (MT), Dargol (NM), Echolake (CO), Fortlewis (CO), Heckly (NM), Ligocki (NM), Lubrecht (MT), Ordnance (NM), Rittel (MT), and Valnor (NM) series. Crow, Dargol, Rittle, and Valnor soils all have hues of 2.5Y. Heckly soils formed from sandstone and siltstone. Crow soils are very deep. Dargol soils have Oi and E horizons. Heckly soils are redder than 7.5YR. Ordnance soils are inactive. Crow, Echolake, Fortlewis, Lubrecht, and Rittel soils are in LRR-E and are moist in May and June.
GEOGRAPHIC SETTING: The Zuni soils, formed in residuum derived from gneissic-granite and are on mountain sideslopes and domes. Slopes are 1 to 15 percent. Elevations range from 7,800 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 Cinnadale, Heckly, Ligocki, Mirabal, and Robolata soils. The Cinnadale and Heckly soils are shallow and are on hills and ridges. The Ligocki and Robolata soils are very deep and are on fan remnants and stream terraces. The Mirabal soils are loamy-skeletal and are on steeper mountain sideslopes.
DRAINAGE AND PERMEABILITY: Well drained, medium to high runoff, and slow permeability.
USE AND VEGETATION: This series is used for wood products, limited livestock grazing, and wildlife habitat. The present vegetation is a ponderosa pine woodland with associated Rocky Mountain juniper. Understory vegetation is Gambel oak, mountain muhly, Arizona fescue, pine dropseed, bottlebrush squirreltail, prairie junegrass, and muttongrass.
DISTRIBUTION AND EXTENT: West central, New Mexico. MLRA 35, LRR-D. This series is of moderate, extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: McKinley County (Zuni Mountains Area) New Mexico, 1964.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: The zone from 0 to 3 inches. (A horizon)
Argillic horizon: The zone from 3 to 27 inches. (Bt horizons)
Lithic contact: 26 inches-gneissic-granite (R horizon)
Classified according to Soil Taxonomy Second Edition, 1999; Keys to Soil Taxonomy Tenth Edition, 2006.
The series was originally written with depth class ranging from moderately deep to deep. The series is being redefined as a moderately deep soil.
The mineralogy class was changed from smectitic to mixed, superactive cation exchange activity class was added, and the type location was moved in December 2000.
ADDITIONAL DATA: Mineralogy data S95NM-031-001, NSSC-Soil Survey Lab