LOCATION PROVO              UT
Established Series
Rev. JLS/MJD
12/2009

PROVO SERIES


The Provo series consists of very deep, poorly drained soils that were formed in gravelly alluvium derived from igneous, sandstone, limestone, and quartzite rocks. These soils are on nearly level to gently sloping alluvial fans and floodplains. Slopes are 0 to 3 percent. The mean annual temperature is about 9.0 degrees C., and the average annual precipitation is about 360 mm.

TAXONOMIC CLASS: Sandy-skeletal, mixed, mesic Fluvaquentic Endoaquolls

TYPICAL PEDON: Provo gravelly fine sandy loam, cultivated. (Colors are for dry soil unless otherwise noted.)

Ap--0 to 18 cm; dark gray (10YR 4/1) gravelly fine sandy loam, very dark gray (10YR 3/1) moist; weak fine subangular blocky structure; slightly hard, friable, slightly sticky, plastic; few medium and common fine roots; common very fine discontinuous pores; slightly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (10 to 23 cm thick)

Ag--18 to 38 cm; dark gray (10YR 4/1) gravelly fine sandy loam, very dark gray (10YR 3/1) moist, few fine distinct dark reddish brown (5YR 3/4) redoximorphic concentrations; weak medium subangular blocky structure; slightly hard, friable, slightly sticky, plastic; few medium and common fine roots; common very fine continuous pores; slightly effervescent; moderately alkaline (pH 8.1); clear smooth boundary. (13 to 20 cm thick)

2Cg1--38 to 64 cm; dark gray (10YR 4/1) very gravelly sand, very dark grayish brown (10YR 3/2) moist, few coarse distinct yellowish brown (10YR 5/4) redoximorphic concentrations; single grain; loose; common very fine roots; slightly effervescent; moderately alkaline (pH 8.1); gradual smooth boundary. (18 to 48 cm thick)

2Cg2--64 to 102 cm; grayish brown (10YR 5/2) very gravelly loamy sand, dark grayish brown (10YR 4/2) moist, common medium distinct very dark brown (10YR 2/2) redoximorphic concentrations that occur as iron stains on the gravel; single grain; loose; common very fine roots; slightly effervescent; moderately alkaline (pH 8.1); gradual smooth boundary. (25 to 74 cm thick)

2Cg3--102 to 152 cm; gray (10YR 5/1) very gravelly sand, dark grayish brown (10YR 4/2) moist; common medium distinct very dark brown (10YR 2/2) redoximorphic concentrations that occur as iron stains on the gravel; single grain; loose; slightly effervescent; moderately alkaline (pH 8.1).

TYPE LOCATION: Utah County, Utah; about 5 km north of Provo, near Provo River; 793 m east and 549 m south of the NW corner of sec. 25, T.6S., R.2E.; USGS Orem 7.5 minute quadrangle; lat. 40 degrees 16 minutes 13.4 seconds N. and long. 111 degrees 40 minutes 0.3 seconds W., UTM Zone 12 443311e 4457981n, NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: These soils have a water table within 75 cm of the surface unless drained; aquic soil moisture regime
Mean annual soil temperature: 8.0 to 12.2 degrees C
Mean summer soil temperature: 17.2 to 21.1 degrees C

Mollic epipedon: 25 to 60 cm thick
Organic carbon content: 0.3 percent or more in all horizons within 125 cm of the surface
Reaction: slightly alkaline to moderately alkaline
Effervescence: slightly to strongly effervescent
Calcium carbonate equivalent: 3 to 15 percent
Other features: A thin O horizon is at the surface of some pedons

Particle-size control section (weighted average):
Texture: dominantly sand, loamy sand, or loamy fine sand
Sand content: More than 15 percent coarser than very fine sand
Rock fragments: 50 to 80 percent gravel or cobbles

A horizon:
Value: 4 or 5 dry
Chroma: 1 if no redoximorphic features, and 1 and 2 if these features are present
Structure: weak, fine or medium subangular blocky or moderate fine granular

C horizon:
Value: 4 through 6 dry, 3 or 4 moist
Chroma: 1 if no redoximorphic features, and 2 if these features are present
Redoximorphic features: typically iron staining on the gravel, but are in the soil matrix in some pedons
SAR: 0 to 13

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING:
Elevation: 1,371 to 1,810 meters
Landform: nearly level to gently sloping alluvial fans and floodplains
Slope: 0 to 3 percent
Parent material: gravelly alluvium derived from igneous, sandstone, limestone, shale and quartzite rocks.
Mean annual air temperature: 7.0 to 11.1 degrees C.
Mean summer temperature: 18.0 to 21.1 degrees C.
Mean annual precipitation: 280 to 400 mm; the climate is dry subhumid
Frost-free period: 100 to 150 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Sunset soils. Sunset soils have chroma of 2 or 3 in the A and C horizons and have less than 35 percent rock fragments.

DRAINAGE AND PERMEABILITY: Poorly drained; slow runoff; rapid permeability; moderately high or high saturated hydraulic conductivity.

USE AND VEGETATION: Irrigated cropland producing alfalfa, small grains, orchards, and pasture. Principal native plants are willows, wild rosebush, cottonwoods, meadow grasses, and sedges.

DISTRIBUTION AND EXTENT: These soils are inextensive and are of minor importance for cultivated crops. They are more important for grazing and occur adjacent to drainages along the Wasatch Front and other irrigated valleys in central and north-central Utah. MLRA 28A.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona

SERIES ESTABLISHED: Utah County (Provo-Goshen Valley Area), Utah, 1939.

REMARKS:
December, 2009 reclassified from Typic to Fluvaquentic Endoaquolls to better fit the organic carbon distribution in the profile.

Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon - the zone from the surface to 38 cm (Ap and Ag horizons).
Redoximorphic concentrations - in the zone from 18 to 152 cm (Ag, 2Cg1, 2Cg2, 2Cg3 horizons).
Reduced matrix throughout.
Particle-size control section - the zone from 25 to 100 cm.

Classification: Keys to Soil Taxonomy, Tenth Edition, 2006.


National Cooperative Soil Survey
U.S.A.