LOCATION PROCKY                  AZ

Established Series
Rev. MAC/GWA/JMH
02/2025

PROCKY SERIES

The Procky series consists of moderately deep or deep, well drained soils that formed in colluvium over residuum derived from basalt. Procky soils are on bases of hillslopes. Slopes range from 2 to 15 percent. Mean annual precipitation is about 20 inches and the mean annual temperature is about 48 degrees F.

TAXONOMIC CLASS: Clayey-skeletal, mixed, superactive, mesic Typic Argiustolls

TYPICAL PEDON: Pluto-Procky complex (Colors are for dry soil unless otherwise noted.)

A--0 to 4 inches (0 to 10 cm); reddish brown (5YR 4/3) very gravelly silty clay loam, dark reddish brown (5YR 3/3) moist; moderate medium granular; friable, moderately sticky, moderately plastic; many fine and medium irregular, and common medium tubular pores; many fine roots throughout; 1 percent boulders, 5 percent stones, 10 percent cobbles, and 30 percent gravel; noneffervescent; neutral (6.6 pH); clear smooth boundary

Bt1--4 to 12 inches (10 to 30 cm); reddish brown (5YR 4/3), extremely stony clay, dark reddish brown (5YR 3/3) moist; moderate fine angular blocky; firm, very sticky, very plastic; common fine and medium tubular pores; common fine and medium roots throughout; 20 percent distinct clay films on all faces of peds and on rock fragments; 10 percent boulders, 20 percent stones, 20 percent cobbles, and 10 percent gravel; noneffervescent; slightly acid (6.4 pH); gradual wavy boundary

Bt2--12 to 20 inches (30 to 50 cm); reddish brown (5YR 4/3) very stony clay, reddish brown (5YR 4/4) moist; weak fine subangular blocky; firm, very sticky, very plastic; common fine and medium tubular pores; common fine and medium roots throughout; 10 percent distinct clay films on all faces of peds and on rock fragments; 20 percent stones, 20 percent cobbles, and 5 percent gravel; noneffervescent; slightly acid (6.4 pH); gradual wavy boundary

Bt3--20 to 28 inches (50 to 70 cm); reddish brown (5YR 4/3) very cobbly clay, reddish brown (5YR 4/4) moist; weak fine subangular blocky; firm, very sticky, very plastic; common fine, medium, and coarse tubular pores; 10 percent distinct clay films on all faces of peds and on rock fragments, and 10 percent distinct pressure faces; 10 percent stones, 20 percent cobbles, and 10 percent gravel, noneffervescent; neutral (6.6 pH); gradual wavy boundary

R--28 to 60 inches (70 to 152 cm); basalt bedrock

TYPE LOCATION: Coconino County, Arizona; located about 9.8 kilometers (6.1 miles) south southeast of Munds Park, Arizona; USGS Quadrangle Stoneman Lake; Latitude 34.861511, Longitude -111.604990, Datum WGS84.

RANGE IN CHARACTERISTICS:
Soil moisture regime: typic ustic
Mean annual soil temperature: 46 to 50 degrees F
Rock fragment content: 35 to 60 percent
Depth to lithic contact: over 50 inches
Particle-size control section:
Clay content: 35 to 60 percent

A horizon
Hue: 5YR or 7.5YR
Value: 4 or 5 (3 or 4 moist)
Chroma: 2 or 3, dry or moist
Calcium carbonate equivalent: 0 to 2 percent
Reaction: neutral to slightly alkaline

B horizon
Hue: 5YR or 7.5YR
Value: 4 or 5 (3 or 4 moist)
Chroma: 3 or 4, dry or moist
Texture: clay
Calcium carbonate equivalent: 0 to 2 percent
Sodium Adsorption Ratio (SAR): 0 to 2
Reaction: slightly acid to slightly alkaline

COMPETING SERIES: These are the Gavilan and Modeama series.
Gavilan soils have a calcic horizon and should be reclassified. Modeama soils are moderately deep to limestone, and are frequently moist in May, and June.

GEOGRAPHIC SETTING:
Parent material: colluvium over residuum derived from basalt
Landform: lava fields
Slopes: 2 to 15 percent
Elevation: 6,500 to 7,600 feet
Mean annual air temperature: 45 to 49 degrees F
Mean annual precipitation: 18 to 22 inches
Precipitation peaks in July and August, and in winter. May and June are much drier.
Frost-free period: 120 to 140 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Pluto and Grandwash soils. Pluto soils are in residuum and have substantially less fragments. Grandwash soils are shallow to bedrock and are on sideslopes and shoulders.

DRAINAGE AND PERMEABILITY: well drained, slow permeability

USE AND VEGETATION: These soils are used principally used as habitat for wildlife. Native vegetation is mainly ponderosa pine, alligator juniper, Arizona fescue, Gambel oak and pine dropseed.

DISTRIBUTION AND EXTENT: Northern Arizona. MLRA 39.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.

SERIES ESTABLISHED: Coconino County, Arizona.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: from 0 to 30 centimeters. (A and Bt1 horizon)
Argillic horizon: from 10 to 70 centimeters. (Bt horizons).
Lab pedon #: 13N0002
Name is derived from nearby Rocky Park
Taxonomic Version: Keys to Soil Taxonomy, Thirteenth Edition, 2022
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National Cooperative Soil Survey
U.S.A.