LOCATION MONTVALE UTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Aridic Lithic Argiustolls
TYPICAL PEDON: Montvale very stony very fine sandy loam, woodland-range. (Colors are for dry soil unless otherwise noted.)
A--0 to 3 inches; brown (7.5YR 5/4) very stony very fine sandy loam, reddish brown (5YR 5/4) moist; weak thick platy structure that parts to weak very fine granular; soft, friable, slightly sticky and slightly plastic; few fine roots; 30 percent stones and cobbles and 10 percent pebbles; noncalcareous; slightly alkaline (pH 7.8); abrupt smooth boundary. (2 to 4 inches thick)
B--3 to 7 inches; reddish brown (5YR 5/3) very stony very fine sandy loan, dark reddish brown (5YR 3/3) dry; weak thick platy structure that parts to weak medium angular blocky; hard, firm, slightly sticky and slightly plastic; many fine roots; few fine pores; 25 percent stones and cobbles and 10 percent pebbles; noncalcareous; slightly alkaline (pH 7.7); clear wavy boundary.
Bt--7 to 13 inches; reddish brown (5YR 5/3) very stony loam, dark reddish brown (5YR 3/3) moist; weak medium prismatic structure that parts to weak subangular blocky; very hard, firm, slightly sticky and slightly plastic; few fine, medium and coarse roots; many fine pores; few thin clay films in channels; 25 percent stones and cobbles and 15 percent pebbles; noncalcareous; slightly alkaline (pH 7.6); gradual wavy boundary. (3 to 6 inches thick)
Bk--13 to 18 inches; reddish brown (5YR 4/4) very stony loam, reddish brown (5YR 4/4) moist; weak coarse prismatic structure that parts to moderate medium subangular blocky; very hard, very firm, sticky and plastic; many fine roots; many fine pores; few thin clay films in channels; 30 percent stones and cobbles and 10 percent pebbles; strongly calcareous; moderately alkaline (pH 8.0); gradual wavy boundary. (2 to 5 inches thick)
R--18 inches; sandstone, partially decomposed and fractured, grading into consolidated hardrock.
TYPE LOCATION: San Juan County, Utah; Summit Point area; about 0.4 miles west of the SE corner of section 9, T.33S., R.26E., SLBM.
RANGE IN CHARACTERISTICS:
Thickness of the mollic epipedon: 7 to 19 inches
Depth to bedrock: 7 to 19 inches.
Depth to the carbonate accumulation: 6 to 14 inches
Rock fragments: dominantly angular stones and cobbles, but some are gravel
Rock fragments: 25 to 50 percent in individual horizons, but average 35 percent or more by volume in the series control section
Mean annual soil temperature: 48 to 52 degrees F. at a depth immediately above the bedrock
Soil moisture: Aridic ustic moisture regime.
A horizon
Hue: 7.5YR or 5YR
Value: 4 or 5 dry, 3 or 3.5 moist
Chroma: 3 or 3.5 dry, 2 through 4 moist. After mixing, the moist chroma is 2 or 3 to a depth of 7 or more inches
Texture: very stony very fine sandy loam or very stony loam.
Bt horizon
Value: 4 or 5 dry, 3 or 4 moist
Chroma: 3 or 4
Texture: very stony loan, but ranges to very stony light sandy clay loan.
Bk horizon
Value: 4 or 5 dry, 3 or 4 moist
Chroma: 3 or 4
Texture: very stony loam, but ranges to very stony very fine sandy loam or fine sandy loam
Calcium carbonate: moderately or strongly calcareous
Organic matter: Typically an accumulation of organic matter occurs just above the bedrock. Commonly the Btk horizon is higher in organic matter than either the Al or B2t horizons.
COMPETING SERIES: These are the Buckspring (NV), Motoqua (UT), Santa Fe (NM), and Slidymtn (NV) soils. Buckspring soils have hue of 10YR. Motoqua, Santa Fe, and Slidymtn soils lack horizons of carbonate accumulation.
GEOGRAPHIC SETTING: Montvale soils are on ridges, uplands and plains at elevations of 5,800 to 7,500 feet. Slopes range from 2 to 25 percent. These soils formed in material weathered from sandstone. The mean annual temperature is 47 to 51 degrees F. The mean summer temperature is 58 to 70 degrees F. Average annual precipitation is 13 to 15 inches. The frost-free season is 105 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Monticello and Northdale soils. Monticello soils are more than 40 inches deep to bedrock. Northdale soils are 20 to 40 inches deep to bedrock.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: Used mainly for woodland, range and wildlife habitat. Vegetation is dominantly black sagebrush, big sagebrush, pinyon, juniper, snakeweed, Indian ricegrass, needleandthread and blue grama.
DISTRIBUTION AND EXTENT: Colorado plateau of southeastern Utah and southwestern Colorado. MLRAs 35, 39 & 48A. These soils are extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: San Juan County, Utah 1960.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: the zone from 0 to 13 inches (A, B & Bt horizons)
Argillic horizon: the zone from 7 to 13 inches (Bt horizon)
Lithic contact: 18 inches (R horizon)