LOCATION VIGIL                   CO+NM

Established Series
Rev. JPP/KLS
04/2018

VIGIL SERIES


The Vigil series consists of very deep, well drained soils that formed in alluvium derived from mixed sources. Vigil soils are on flood-plain steps. Slopes range from 0 to 3 percent. Mean annual precipitation is about 406 mm and the mean annual air temperature is about 8.9 degrees C.

TAXONOMIC CLASS: Sandy-skeletal, mixed, mesic Oxyaquic Ustifluvents

TYPICAL PEDON: Vigil very gravelly loamy fine sand, on a south facing, simple, 1 percent slope in rangeland at an elevation of 1,951 meters. (Colors are for dry soil unless otherwise noted.) When described on August 28, 2005 the soil was moist from 0 to 203 cm. The surface is covered with about 5 percent cobbles.

A--0 to 8 cm; grayish brown (10YR 5/2), very gravelly loamy fine sand, dark grayish brown (10YR 4/2) moist; weak fine granular structure; very friable, soft, nonsticky, nonplastic; common fine and very fine roots throughout; 35 percent gravel, and 10 percent cobbles; slightly alkaline (pH 7.4); clear smooth boundary. (5 to 20 cm thick)

C1--8 to 46 cm; brown (10YR 5/3), extremely gravelly loamy sand, brown (10YR 4/3) moist; single grain; loose, nonsticky, nonplastic; many fine and very fine roots throughout; 45 percent gravel, 20 percent cobbles, and 1 percent stones; slightly alkaline (pH 7.4); gradual smooth boundary.

C2--46 to 173 cm; brown (10YR 5/3), stratified extremely gravelly coarse sand to extremely cobbly loamy coarse sand, brown (10YR 4/3) moist; single grain; loose, nonsticky, nonplastic; few fine and very fine roots throughout; 35 percent gravel, 30 percent cobbles, and 3 percent stones; slightly alkaline (pH 7.4); gradual smooth boundary. (combined thickness of C1, C2 - 45 to 230 cm)

C3--173 to 203 cm; brown (10YR 5/3) stratified extremely gravelly coarse sand to extremely cobbly loamy coarse sand, brown (10YR 4/3) moist; single grain; loose, nonsticky, nonplastic; few medium distinct brownish yellow (10YR 6/6) dry, and yellowish brown (10YR 5/6) moist, masses of oxidized iron on bottom of rock fragments; 35 percent gravel, 30 percent cobbles, and 3 percent stones; slightly alkaline (pH 7.4).

TYPE LOCATION: Archuleta County, Colorado; about 8 kilometers east of Pagosa Junction; located about 488 meters north and 640 meters west of the southeast corner of Sect. 2, T 32 N., R 3 W.; USGS Pagosa Junction topographic quadrangle; Lat. 37 degrees, 2 minutes, 36 seconds, N. and Long. 107 degrees, 8 minutes, 38 seconds, W., NAD 27.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 8.3 to 10.0 degrees C.
Mean summer soil temperature: 15.6 to 18.3 degrees C.
Depth to redox concentrations: 76 to 178 cm
Depth to endosaturation: 76 to 152 cm

Particle-size control section: (weighted average)
Clay content: 0 to 12 percent
Sand content: 75 to 95 percent
Rock fragments: 35 to 75 percent

A horizon
Hue: 7.5YR or 10YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2 or 3, dry or moist
Texture: very gravelly loamy fine sand
Clay content: 5 to 15 percent
Rock fragments: 35 to 60 percent
Reaction (pH): 6.6 to 7.8

C horizon, upper part
Hue: 7.5YR or 10YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2 to 4, dry or moist
Texture: extremely cobbly loamy sand, extremely gravelly loamy sand, very gravelly loamy sand, very cobbly loamy sand
Clay content: 0 to 12 percent
Rock fragments: 35 to 75 percent
Reaction (pH): 6.6 to 7.8

C horizon, lower part
Hue: 7.5YR or 10YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2 to 4, dry or moist
Texture: stratified very cobbly sand to very gravelly loamy sand, stratified extremely gravelly sand to extremely gravelly loamy sand, stratified extremely gravelly coarse sand to extremely cobbly loamy coarse sand
Clay content: 0 to 12 percent
Rock fragments: 35 to 75 percent
Reaction (pH): 6.6 to 7.8

COMPETING SERIES:
Abiquiu (NM) - have a mean annual soil temperature greater than 10.0 C.

GEOGRAPHIC SETTING:
Landform - flood-plain steps
Elevation - 1,860 to 2,350 meters
Slopes - 0 to 3 percent
Parent material - alluvium derived from mixed sources
Mean annual air temperature - 7.2 to 10.0 degrees C.
Mean annual precipitation - 350 to 460 mm
Precipitation pattern - May and June are the driest months, July and August are wettest
Frost-free period - 100 to 125 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed.

DRAINAGE AND PERMEABILITY: Well drained, low runoff, rapid permeability. These soils are rarely flooded for short periods during the months of May and June.

USE AND VEGETATION: Used for livestock grazing and wildlife habitat. Vegetation consists of cottonwood, thinleaf alder, blue grama, western wheatgrass, squirreltail, and sand dropseed.

DISTRIBUTION AND EXTENT: Southwestern Colorado; LRR D, MLRA 36; small extent.

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

SERIES PROPOSED: Archuleta County, Colorado, Archuleta soil survey area, 2005. The name is from a mesa in the survey area.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Redoximorphic concentrations - 173 to 203 cm (C3 horizon)
Endosaturation - saturated from 173 to 203 cm (C3 horizon)
Particle size control section - 25 to 100 cm (part of the C1 and C2 horizons)

Vigil soils have a mesic temperature regime and are in an ustic soil moisture regime with an oxyaquic subclass.

Permeability is estimated at 15.0 to 51.0 cm/hr (rapid).


National Cooperative Soil Survey
U.S.A.