LOCATION ROQUES                  NM+CO

Established Series
Rev. MWR-TWH-KLS
02/2018

ROQUES SERIES

The Roques series consists of very deep, well drained, very slowly permeable soils that formed in alluvium from shale. Roques soils are on valley sides and alluvial fans and have slopes of 2 to 8 percent. The mean annual air temperature is about 6.1 degrees C., and the mean annual precipitation is about 432 mm.

TAXONOMIC CLASS: Fine, mixed, superactive, frigid Vertic Haplustepts

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

A--0 to 5 cm; light olive brown (2.5Y 5/4) clay loam, olive brown (2.5Y 4/4) moist; weak fine granular structure; soft, friable, moderately sticky and moderately plastic; few fine roots; few fine interstitial pores; neutral; abrupt smooth boundary. (3 to 13 cm thick)

Bw--5 to 38 cm; light olive brown (2.5Y 5/4) clay, olive brown (2.5Y 4/4) moist; weak coarse prismatic structure parting to weak coarse subangular blocky; very hard, firm, very sticky and very plastic; few very fine and fine roots; few fine tubular pores: slightly effervescent; slightly alkaline; gradual smooth boundary. (25 to 51 cm thick)

Bk--38 to 152 cm; light olive brown (2.5Y 5/4) clay, olive brown (2.5Y 4/4) moist; massive; very hard, very firm, very sticky and very plastic; few very fine roots; few fine tubular pores; strongly effervescent; few fine soft masses of calcium carbonate; slightly alkaline.

TYPE LOCATION: Rio Arriba County, New Mexico; 4 kilometers west and 7.2 kilometer south of Chama. Brazos USGS quad; New Mexico state plane coordinates 647,161 meters north and 119,570 meters east; Long. 106 degrees, 37 minutes, 01 seconds west; Lat. 36 degrees, 50 minutes, 03 seconds north.

RANGE IN CHARACTERISTICS:
Average Annual Soil Temperature: 5.6 to 8.3 degrees C.
Linear extensibility: 6.0 to 8.0 percent (estimated)

Control section - percent clay: 40 to 55 percent

A horizon
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2 through 4; dry or moist
Calcium carbonate equivalent: 1 to 5 percent
Reaction (pH): 6.6 to 7.8

Bw horizon
Value: 5 through 7 dry, 4 or 5 moist
Chroma: 2 through 4; dry or moist
Calcium carbonate equivalent: 1 to 5 percent
Reaction (pH): 6.6 to 7.8

Bk horizon
Value: 5 through 7 dry, 4 or 5 moist
Chroma: 2 through 4, dry or moist
Calcium carbonate equivalent: 5 to 15 percent
Reaction (pH): 7.4 to 8.4

COMPETING SERIES: None listed.

GEOGRAPHIC SETTING:
Landform - valley sides and alluvial fans
Elevation - 2,225 to 2,440 meters
Slopes - 2 to 8 percent
Parent material - alluvium from shale, including the Mancos Formation Average annual air temperature - 5.6 to 6.7 degrees C.
Average annual precipitation - 400 to 460 mm
Soil moisture - intermittently moist in some part December through April and July through September
Frost-free period - 80 to 100 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed.

DRAINAGE AND PERMEABILITY: Well drained; medium runoff; very slow permeability.

USE AND VEGETATION: Roques soils are used for livestock grazing and wildlife habitat. The present vegetation is western wheatgrass, sleepygrass, and western yarrow.

DISTRIBUTION AND EXTENT: Northern New Mexico, southwestern Colorado. LRR D, E; MLRA 36, 48A; moderate extent.

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

SERIES ESTABLISHED: Rio Arriba County, New Mexico, 1989.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Cambic horizon - 5 to 38 cm (Bw horizon)
Vertic feature is based on estimated linear extensibility.

Note: the carbonate content of the Bk horizon is assumed to be typically less than 15 percent, this needs to be verified.

Roques soils have a frigid temperature regime and are in an ustic soil moisture regime with a typic subclass.

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National Cooperative Soil Survey
U.S.A.