LOCATION CRUBAS                  NM

Established Series
Rev. MWR/RJA/KLS
01/2023

CRUBAS SERIES

The Crubas series consists of very deep, poorly drained, slowly permeable soil that formed in alluvium from metamorphic rock. Crubas soils are on valley bottoms and swales. Slopes are 0 to 5 percent. Mean annual precipitation is about 840 mm and the mean annual air temperature is about 2 degrees C.

TAXONOMIC CLASS: Fine, mixed, superactive Typic Cryaquolls

TYPICAL PEDON: Crubas clay loam - meadow. (Colors are for dry soil unless otherwise noted.)

O--0 to 8 cm; partly decomposed organic matter.

A--8 to 38 cm; dark grayish brown (10YR 4/2) clay loam, very dark brown (10YR 2/2) moist; common medium distinct strong brown (7.5YR 5/8) mottles; weak fine granular structure; soft, very friable, sticky and plastic; many fine and very fine roots; common fine and very fine interstitial pores; strongly acid; abrupt smooth boundary. (18 to 36 cm thick)

Cg1--38 to 94 cm; gray (10YR 6/1) clay, gray (10YR 5/1) moist; common medium distinct strong brown (7.5YR 5/8) mottles; massive; very hard, firm, very sticky and very plastic; few fine and very fine roots; few fine and common very fine tubular pores; strongly acid; clear wavy boundary. (46 to 100 cm thick)

2Cg2--94 to 160 cm; gray (10YR 6/1) gravelly clay, gray (10YR 5/1) moist; many large distinct strong brown (7.5YR 5/8) mottles; massive; hard, firm, very sticky and very plastic; few very fine roots; few very fine tubular pores; 20 percent pebbles; strongly acid.

TYPE LOCATION: Rio Arriba County, New Mexico; about 20 km east and 6 km south of Chama, NM; lat. 36 degrees, 51 minutes, 19 seconds N, long. 106 degrees, 27 minutes, 08 seconds W

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--3 to 4 degrees C
Mean summer soil temperature--4 to 6 degrees C
Soil moisture--saturated in winter, spring and early summer. This soil is associated with seeps and springs
Depth to mottles--0 to 15 cm
Thickness of mollic epipedon--18 to 36 cm
Depth to water table--0 to 50 cm
Particle-size control section:
Clay content--35 to 50 percent
Reaction--pH 5.1 to 6.1

A horizon
Value--2 or 3 moist

Cg horizon
Value--5 or 6 dry
Chroma--1 or 2

2Cg horizon
Value--5 or 6 dry
Chroma--1 or 2
Rock fragment content--15 to 30 percent pebbles

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING:
Landform--valley bottoms and swales
Elevation--2925 to 3175 meters
Slope--0 to 5 percent
Parent material--alluvium from metamorphic rock
Mean annual precipitation--760 to 890 mm
Mean annual air temperature--2 to 3 degrees C
Frost-free period--50 to 70 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed

DRAINAGE AND PERMEABILITY: Poorly drained; slow runoff; slow permeability; water table 0 to 50 cm; and occasionally flooded

USE AND VEGETATION: Crubas soils are used for livestock grazing and wildlife habitat. The present vegetation is bluegrass, sedges, rushes, alpine timothy, shrubby cinquefoil, clover and tufted hairgrass.

DISTRIBUTION AND EXTENT: Crubas soils are of small extent in the northcentral mountains of New Mexico; MLRA 48A

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Rio Arriba County, New Mexico, 1989. The series name is coined.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon--8 to 38 cm (A horizon)
Particle-size control section--25 to 100 cm (part the A, all of the Cg1, and part of the 2Cg2 horizons)

Converted to metric and O horizons were updated to start at zero. Competing series section was not updated. 12/2022

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National Cooperative Soil Survey
U.S.A.