LOCATION RETSOVER           AZ
Established Series
Rev. DJP/JLF/RLB
02/2007

RETSOVER SERIES


The Retsover series consists of deep, well drained soils on mesas and plateaus. These soils formed in residuum and local alluvium derived dominantly from sedimentary rocks. Slopes range from 1 to 15 percent. The mean annual precipitation is about 17 inches. The mean annual air temperature is 47 degrees F.

TAXONOMIC CLASS: Fine, smectitic, mesic Vertic Haplustalfs

TYPICAL PEDON: Retsover gravelly loam - woodland. (Colors are for dry soil unless otherwise noted.)

Oi--0 to 1 inch; recent pine litter.

Oe--1 to 2 inches; partially decomposed leaf litter.

A--2 to 3 inch; dark brown (10YR 3/3) gravelly loam, very dark brown (10YR 2/2) moist; moderate fine granular structure; soft, very friable, slightly sticky and slightly plastic; common very fine roots; many very fine irregular pores; 15 percent gravel; noneffervescent; slightly acid (pH 6.3); abrupt smooth boundary. (1 to 6 inches thick)

E--3 to 5 inches; brown (10YR 4/3) loam, dark brown (10YR 3/3) moist; moderate thick platy structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; many very fine irregular, and common very fine and fine tubular pores; noneffervescent; slightly acid (pH 6.1); abrupt wavy boundary. (0 to 4 inches thick)

Bt1--5 to 11 inches; dark brown (10YR 3/3) clay loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and plastic; common very fine, few fine and medium roots; common very fine and few fine tubular pores; 5 percent gravel; few faint clay films in larger pores; noneffervescent; slightly acid (pH 6.1); abrupt wavy boundary. (6 to 16 inches thick)

Bt2--11 to 21 inches; reddish brown (5YR 4/4) clay, reddish brown (5YR 4/4) moist; moderate coarse prismatic structure; very hard, very firm, very sticky and very plastic; common very fine, and few fine, medium, and coarse roots; few very fine tubular pores; 5 percent gravel; common faint to distinct clay films in pores, many pressure faces; noneffervescent; slightly acid (pH 6.4); clear wavy boundary. (4 to 10 inches thick)

Bt3--21 to 36 inches; reddish brown (5YR 4/4) clay, reddish brown (5YR 4/4) moist; strong coarse prismatic structure; very hard, very firm, very sticky and very plastic; few very fine, fine, coarse and common medium roots; few very fine tubular pores; 10 percent gravel; common faint clay films on ped faces, many pressure faces; noneffervescent; neutral (pH 6.8); abrupt irregular boundary. (9 to 24 inches thick)

Btk--36 to 46 inches; yellowish red (5YR 4/6) and reddish yellow (5YR 7/6) extremely cobbly clay, reddish brown (5YR 4/4) and reddish yellow (5YR 6/6) moist; weak fine subangular blocky structure; very hard, very firm, very sticky and very plastic; few very fine and fine roots; few very fine tubular pores; 30 percent cobble and 30 percent gravel; few faint clay films on ped faces and rock fragments; common coarse soft masses of calcium carbonate; noneffervescent matrix with violently effervescent features; slightly alkaline (pH 7.4); abrupt wavy boundary. (9 to 23 inches thick)

R--46 inches; limestone.

TYPE LOCATION: Coconino County, Arizona; on the Hualapai Indian Reservation; 2400 feet east and 1800 feet north of the southwest corner of Section 27, T.29N., R.8W.

RANGE IN CHARACTERISTICS:

Soil Moisture: Intermittently moist in some part of the soil moisture control section during January - March and July - September. Driest during May and June. Approximately 60 percent of the precipitation occurs during the winter months. Typic ustic soil moisture regime.

Soil Temperature: 47 to 51 degrees F.

Depth to bedrock: 40 to 60 inches

Clay Content: averages from 40 to 55 percent in the particle size control section, but ranges from 35 to 60 percent in individual horizons.

Linear extensibility: 6.0 cm or more from the surface to 40 inches

Other features: Oe and/or E horizons are absent in some pedons.

A horizon
Hue: 7.5YR, 10YR
Value: 3 to 5 dry, 2 or 3 moist
Chroma: 2 to 4, dry or moist
Rock fragments: 15 to 35 percent gravel and 0 to 5 percent cobbles

E horizon
Hue: 7.5YR, 10YR
Value: 4 or 5 dry
Chroma: 3 or 4 dry, 2 to 4 moist
Textures: loam, clay loam
Rock fragments: less than 10 percent gravel

Bt horizon
Hue: 5YR, 7.5YR, 10YR
Value: 3 to 6, dry or moist
Chroma: 3 to 6 dry, 2 to 6 moist
Textures: clay loam, clay
Rock fragments: averages less than 20 percent gravel

Btk horizon
Value: 4 to 8 dry, 4 to 7 moist
Chroma: 3 to 6, dry or moist
Rock fragments: 0 to 30 percent gravel and 0 to 30 percent cobble

COMPETING SERIES: These are Disterheff (AZ) and Hermshale (AZ) series.
Disterheff soils are very deep.
Hermshale soils have a mean annual soil temperature of 52 to 58 degrees F.

GEOGRAPHIC SETTING: Retsover soils are on plateaus and mesas at elevations of 6600 to 7500 feet. These soils formed in residuum and local alluvium derived dominantly from sedimentary rocks. Slopes range from 1 to 15 percent. The mean annual air temperature is 45 to 49 degrees F. The mean annual precipitation is 17 to 25 inches. The frost-free period is 100 to 150 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are Pinntank and Pocomate series. Pinntank soils are moderately deep to bedrock. Pocomate soils are shallow to bedrock.

DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; slow permeability.

USE AND VEGETATION: Retsover soils are used for timber harvesting, firewood gathering, grazeable woodland, and wildlife habitat. The present vegetation is ponderosa pine, bottlebrush squirreltail, Ross sedge, blue grama, muttongrass, Gambel oak, and Mountain big sagebrush.

DISTRIBUTION AND EXTENT: Northwestern Arizona. This series is not extensive. MLRA 35.

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

SERIES ESTABLISHED: Coconino County, Arizona; Soil survey of Hualapai-Havasupai Area, Parts of Coconino, Mohave and Yavapai Counties; 1993.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon - The zone from 0 to 1 inch (A horizon)

Argillic horizon - The zone from 3 to 44 inches (Bt1, Bt2, Bt3, Btk horizons)

Lithic contact - The boundary at 44 inches (R horizon)

Vertic subgroup - Linear extensibility of 6.0 cm or more to 40 inches


National Cooperative Soil Survey
U.S.A.