LOCATION VASTINE CO+ NMEstablished Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, frigid Typic Endoaquolls
TYPICAL PEDON: Vastine loam - grassland. (Colors are for dry soil unless otherwise noted.)
A--0 to 10 inches; dark gray (10YR 4/1) loam, black (10YR 2/1) moist; moderate very fine granular structure; soft, very friable; slightly alkaline (pH 7.8); gradual smooth boundary. (10 to 24 inches thick)
Bg--10 to 30 inches; light brownish gray (2.5Y 6/2) loam, dark grayish brown (2.5Y 4/2) moist; many large prominent mottles of dark gray (N 4/) and olive brown (2.5Y 4/4) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly plastic; slightly alkaline (pH 7.8); abrupt smooth boundary. (14 to 34 inches thick)
2Cg--30 to 60 inches; gray (10YR 5/1) sand, dark gray (10YR 4/1) moist; common medium distinct olive brown (2.5Y 4/4) mottles; single grained; loose; slightly alkaline (pH 7.8).
TYPE LOCATION: Alamosa County, Colorado; 2,550 feet east and 300 feet north of the SW Corner of Sec 30, T. 38 N., R. 9 E.
RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture regime is aquic
Mean annual soil temperature: 41 to 46 F (5.0 to 7.8 degrees C)
Mean summer soil temperature ranges: 59 to 63 degrees F (15.0 to 17.2 degrees C)
Depth to seasonal high water table and endosaturation is 10 to 20 inches.
The soils range from slightly alkaline to moderately alkaline in the control section.
Exchangeable sodium ranges from 0 to 15 percent in the control section except that a few subhorizons that exceed those ranges occur discontinuously in some pedons.
The upper part of the control section has 15 to 35 percent fine or coarser sand and 0 to 15 percent rock fragments.
The rock fragments are dominantly 1 to 10 inches (3 to 25 centimeters) in diameter.
The depth to the 2C ranges from 20 to 40 inches (51 to 102 centimeters) below the surface.
Redoximorphic features are evident from 10 inches (25 centimeters) or more from the surface to 60 inches (152 centimeters) or more.
A, Ag, Agb horizon(s):
Hue: 5Y to 7.5YR
Value: 3 to 5, 2 or 3 moist
Chroma: 1 or 2
Fragments: 0 to 15 percent
Calcium carbonate equivalent: 0 to 5 percent
Reaction: pH 7.4 to 8.4
Bg horizon(s):
Hue: 5Y to 7.5YR
Value: 4 to 6, 2 to 5 moist
Chroma: neutral to 8. In some pedons, colors are variegated
Texture: loam, sandy loam, clay loam
Clay content: 18 to 40 percent
Sand content: 0 to 82 percent
Silt content: 10 to 50 percent
Fragments: 0 to 15 percent
Calcium carbonate equivalent: 0 to 5 percent
Reaction: ph 7.4 to 8.4
2Cg horizon(s):
Hue: 5Y to 7.5YR
Value: 4 to 6, 3 to 5 moist
Chroma: 1 to 3 In some pedons, colors in this horizon are variegated
Texture: sand, loamy sand
Clay content: 0 to 15 percent
Sand content: 70 to 100 percent
Silt content: 0 to 30 percent
Fragments: 0 to 15 percent
Calcium carbonate equivalent: 0 to 5 percent
Reaction: pH 6.1 to 8.4
3Cg horizon (if present)
Hue: 7.5YR or 10YR
Value: 4 or 5 dry; 3 to 4 moist
Chroma: 2 to 3 In some pedons, colors in this horizon are variegated
Texture: extremely gravelly sand
Clay content: 0 to 10 percent
Carbonate clay content: 0 to 1 percent
Sand content: 85 to 100 percent
Silt content: 0 to 15 percent
Fragment content, total: 60 to 89 percent
Fragment size and content: 60 to 89 percent indurated gravel
Calcium carbonate equivalent: 0 to 5 percent
Electrical conductivity: 0 to 2 mmhos/cm
Reaction: pH 7.4 to 8.4
Organic matter content: 0.0 to 1.0 percent
COMPETING SERIES: These are the
Blossberg and
Gerrard series.
Blossberg soils have greater then 15 percent coarse fragments at a depth of 20 to 40 inches.
Gerrard soils have sandy-skeletal substratums at depths of 10 to 20 inches.
GEOGRAPHIC SETTING:
Parent material: fine-loamy over sandy and gravelly alluvium derived derived from granite, gneiss, and mica schist
Landform: Low stream terraces and flood plains
Slopes: 0 to 5 percent
Elevation: 7,500 to 8,200 feet (2,286 to 2,743 meters)
Water table: 1 to 2 feet (0.30 to 0.61 meters); keeps soil wet in most seasons
Mean annual air temperature: 40 to 46 degrees F (4.4 to 7.8 degrees C)
Mean summer temperature: 59 to 61 degrees F (15.0 to 16.1 degrees C)
Mean annual precipitation: 6 to 8 inches (152 to 229 millimeters)
Precipitation pattern: Precipitation peaks in July and August occurring as intense summer thunderstorms
Frost free period: 85 to 100 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Medano and
Nortonville soils. Medano soils are coarse-textured.
Nortonville soils have a calcic horizon.
Gerrard soil have sandy-skeletal substratums at depths of 10 to 20 inches.
DRAINAGE AND PERMEABILITY: Poorly to somewhat poorly drained; low runoff; moderate and moderately slow permeability.
Typically the water table fluctuates with the height of the water in the adjacent streams.
These soils are sometimes flooded in the spring.
Water tables may drop as much as 5 feet in the driest parts of the year.
USE AND VEGETATION: These soils are used principally as native pastureland and for irrigated meadows. Occasionally, some areas are used for small grains. Principal native plants are sedges, rushes, saltgrass, and other water-tolerant grasses and plants.
DISTRIBUTION AND EXTENT: High mountain valleys of central Colorado and adjacent parts of New Mexico; LLR E, MLRA 51. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Rio Grande County, Colorado, 1972.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
This soil is saturated from 10 to 80 inches (25 to 203 cm) and has redoximorphic features in this part of the pedon.
Mollic epipedon: 0 to 10 inches, (0 to 25 cm) (A horizon).
Cambic horizon: 10 to 30 inches (25 to 76 cm), (Bg horizon).
Lithologic discontinuity: 30 to 60 inches (76 to 152 cm), (2Cg horizon).
Note: In the past the Vastine series has included soils that were slightly acid and had mean annual precipitation greater than 20 inches. The Vastine Series will include soils that are slightly alkaline and moderately alkaline and have less than 9 inches of mean annual precipitation, 10/08.
Last updated by the state 3/93.
The superactive cation exchange activity class was added in 03/2003 to the taxonomic classification by the National Soil Survey Center on request of the Lakewood MLRA office, without review of the soil series property data.
Taxonomic Version: Tenth edition, 2006