LOCATION WALREES                 NM CO

Established Series
Rev. JBC/JVC/LWH/DKR/WWJ
10/2013

WALREES SERIES

The Walrees series consists of very deep, somewhat poorly drained soils that formed in medium and moderately fine textured alluvium underlain by sand, pebbles, and cobbles. These soils are on flood plains and low river terraces. Slopes are 0 to 2 percent. Average annual precipitation is about 8 inches (203 mm) and average annual temperature is about 53 degrees F (12 degrees C).

TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, calcareous, mesic Oxyaquic Ustifluvents

TYPICAL PEDON: Walrees loam--pastureland. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 6 inches (0 to 15 cm); grayish brown (10YR 5/2) loam, dark brown (10YR 3/3) moist; weak thin and medium platy structure parting to weak fine granular; slightly hard, friable, slightly sticky and slightly plastic; few fine and medium roots; many fine and few medium continuous pores; slightly effervescent; moderately alkaline; clear smooth boundary. (4 to 7 inches or 10 to 18 cm thick)
C1--6 to 18 inches (15 to 46 cm); light brownish gray (10YR 6/2) loam, dark grayish brown (10YR 4/2) moist; few fine distinct yellowish brown (10YR 5/6) redox concentrations; weak medium prismatic structure parting to weak medium subangular blocky; hard, friable, slightly sticky and slightly plastic; many fine and medium roots; few fine and common medium continuous pores; slightly effervescent; moderately alkaline; gradual smooth boundary. (10 to 17 inches or 25 to 43 cm thick)
C2--18 to 30 inches (46 to 76 cm); light brownish gray (10YR 6/2) loam, dark grayish brown (10YR 4/2) moist; few fine distinct yellowish brown (10YR 5/6) redox concentrations; massive; hard, friable, slightly sticky and slightly plastic; many fine and medium roots; few fine and medium continuous pores; strongly effervescent; moderately alkaline; abrupt smooth boundary. (0 to 14 inches or 0 to 36 cm thick)
2C3--30 to 81 inches (76 to 206 cm); stratified sand, pebbles, and cobbles; multicolored due to common distinct redox concentrations.

TYPE LOCATION: San Juan County, New Mexico; in Riverside Park in Aztec; 990 feet west and 990 feet north of the southeast corner of sec. 8, T. 30 N., R. 11 W.; 108 degrees, 0 minutes, 27 seconds west longitude; 36 degrees, 49 minutes, 20 seconds north latitude.

RANGE IN CHARACTERISTICS:
Soil moisture - Typically, the soil moisture control section is intermittently moist in some or all parts less than 40 percent of the time. Moisture accumulates from snowfall in winter, capillary rise above the water table, rainfall, and overbank flooding in the summer. Typic aridic moisture regime based on precipitation. See REMARKS.
Depth to seasonal high water table - 2.0 to 5.0 feet (61 to 152 cm); present either year-round or between April and November
Soil temperature - 53 to 57 degrees F (12 to 14 degrees C).
Depth to lithologic discontinuity of sandy material (2C horizon) - 20 to 40 inches (51 to 102 cm)
Depth to redox concentrations - 0 to 10 inches (0 to 25 cm)
Reaction - moderately to strongly alkaline
Organic matter - 1 to 2 percent in the surface horizon; decreases irregularly with depth; the 2C horizon contains less than 0.8 percent.

A or AC horizon
Hue: 7.5YR or 10YR
Value: 5 or 6 dry, 3 to 5 moist
Chroma: 2 or 3, dry or moist
Texture: loam, clay loam, or fine sandy loam
Electrical conductivity: 2 to 8 mmhos/cm

C horizons
Hue: 7.5YR or 10YR
Value: 5 or 6 dry, 3 to 5 moist
Chroma: 1 to 3, dry or moist
Texture: averages loam or clay loam (18 to 35 percent clay); thin strata ranging from sand to silty clay are present in some pedons.
Electrical conductivity: 2 to 8 mmhos/cm
Redoximorphic features: few to many, fine to medium, distinct or prominent, yellowish brown, dark yellowish brown, or strong brown redox concentrations; thin silty strata derived from shale may have chroma of 1 or 2 which are considered lithochromic colors, and are not interpreted as redox depletions or reduced matrices.

2C horizon
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2 or 3, dry or moist
Texture: stratified sand to gravel or stratified very gravelly coarse sand to sand
Electrical conductivity: 0 to 4 mmhos/cm
Redoximorphic features: few, fine to medium, faint or distinct, dark yellowish brown or strong brown redox concentrations

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: Walrees soils are on flood plains and low river terraces. Slopes are 0 to 2 percent. These soils formed in alluvium of mixed origin or in alluvium derived from sandstone, shale, and quartzite. Elevation is 4,600 to 6,000 feet (1402 to 1829 meters). The climate is arid or semiarid. Average annual precipitation is 5 to 10 inches (127 to 254 mm). Average annual temperature is 50 to 55 degrees F (10 to 13 degrees C). Average frost-free period is 140 to 160 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Apishapa, Bebeevar, Beebe, Green River, Werlog and Youngston soils. Beebe and Bebeevar soils are sandy. Apishapa soils have more than 35 percent clay. Green River soils have less than 18 percent clay. Youngston and Werlog soils lack a contrasting particle-size.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow runoff; moderately slow permeability in the upper part and very rapid permeability below. These soils are subject to occasional or frequent brief periods of flooding between June and September.

USE AND VEGETATION: Used for irrigated crops and pasture, and wildlife habitat. The present vegetation is inland saltgrass, alkali sacaton, fourwing saltbush, Russian-olive, and Fremont cottonwood.

DISTRIBUTION AND EXTENT: Northwestern New Mexico and Southwestern Colorado in the San Juan and Chama River valleys. The series is of small extent. MLRA's 35 and 36.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona

SERIES ESTABLISHED: San Juan County, New Mexico, Eastern Part, 1977.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Entisol feature - the lack of diagnostic surface and subsurface horizons due to continual deposition of fresh sediments and very young soil age
Fluventic feature - alluvial stratification and an irregular organic carbon distribution
Ustic soil moisture regime - the presence of sufficient soil moisture for the ustic regime due to capillary rise above the seasonal high water table and the overbank flooding from perennial streams in summer months.
Oxyaquic subgroup - saturation due to the presence of a seasonal high water table between 24 and 60 inches for more than 1 month in most years. Reduction is assumed not to occur due to the presence of moving, oxygenated groundwater within a very coarse textured substratum that lacks much organic matter. Redox depletions or reduced matrices are not present within the fine-loamy upper portion of the particle-size control section in most pedons.
Contrasting particle-size class - the presence of sandy or sandy-skeletal material within 40 inches of the soil surface (2C horizon)
Note: The classification was changed in 1993 from Aquic Ustifluvents to Oxyaquic Ustifluvents. The Walrees series was mapped with a depth to water table of 2 to 5 feet in the soil survey of San Juan County, New Mexico, Eastern Part. It was mapped with a water table depth of 2 to 4 feet in the soil survey of Rio Arriba County Area, New Mexico. This soil may be moderately well drained where it occurs with a water table depth between 42 and 60 inches (3.5 to 5 ft.). These somewhat drier soils may not have enough natural soil moisture in the soil moisture control section during the warmer months of the year to qualify for the Ustic soil moisture regime, and therefore would be better classified in the new subgroup of Oxyaquic Torrifluvents.

Classified according to Soil Taxonomy Second Edition, 1999; Keys to Soil Taxonomy 11th Edition, 2010.

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National Cooperative Soil Survey
U.S.A.