LOCATION CALGRO CAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Typic Durixerepts
TYPICAL PEDON: Calgro sandy loam, on a slope of less than 1 percent in a leveled alfalfa field at 313 feet elevation. (Colors are for dry soil unless otherwise stated. When described 11/14/89 the soil was slightly moist from 0-25 inches and dry below).
Ap1--0 to 2 inches; brown (10YR 5/3) sandy loam, dark brown (10YR 3/3) moist; moderate thin platy structure; slightly hard, very friable, slightly sticky and nonplastic; few very fine, fine, and medium roots; common very fine tubular, and many very fine vesicular pores; slightly alkaline (pH 7.8); clear smooth boundary.
Ap2--2 to 7 inches; brown (10YR 5/3) sandy loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; hard, friable, nonsticky and nonplastic; common fine and medium roots; common very fine and fine tubular pores; moderately alkaline (pH 8.0); clear gradual boundary.
(Combined thickness of the Ap horizons is 5 to 8 inches).
Bw--7 to 25 inches; yellowish brown (10YR 5/4) sandy loam, dark yellowish brown (10YR 3/4) moist; weak fine subangular blocky structure; hard, friable, nonsticky and nonplastic; few medium, common very fine and fine roots; common very fine and fine tubular pores; moderately alkaline (pH 8.0); abrupt smooth boundary. (15 to 32 inches thick).
2Bqkm--25 to 33 inches; yellowish brown (10YR 5/4) slightly fractured indurated duripan with 1/16 to 1/8 inch thick silica laminae, dark brown (10YR 4/3) moist; massive; extremely hard and extremely firm; few very fine roots in fractures; few fine to very coarse tubular pores; fractures are 1/16 to 1/8 inch thick and are more than 4 inches apart; slightly effervescent matrix with 25 percent violently effervescent spots; 25 percent manganese coatings on pan surface 1/8 to 1/4 inches thick, dark grayish brown (10YR 4/2), and very dark brown (10YR 2/2) moist; clear wavy boundary. (4 to 35 inches thick).
2Bqk--33 to 53 inches; pale brown (10YR 6/3) gravelly loamy sand, dark yellowish brown (10YR 4/4) moist; massive; slightly hard, very friable, nonsticky and nonplastic; common fine and few medium roots; few very fine tubular pores; few thin clay films lining pores; 30 percent of coarse and very coarse angular blocky duripan pieces that are extremely hard and extremely firm; slightly effervescent, disseminated; moderately alkaline (pH 8.4); abrupt smooth boundary. (0 to 25 inches thick)
3Bqkm--53 to 60 inches; yellowish brown (10YR 5/4) slightly fractured indurated duripan, dark yellowish brown (10YR 3/4) moist; massive; extremely hard and extremely firm; 25 percent manganese coatings on ped faces 1/8 to 1/4 inches thick, dark grayish brown (10YR 4/2) and very dark brown (10YR 2/2) moist; slightly effervescent matrix with 35 percent violently effervescent pockets that are very pale brown (10YR 8/2).
TYPE LOCATION: Tulare County, California; 1 mile southwest of Monson; 3/4 mile west of Road 108, 1/2 mile south of Ave. 384; 2,600 feet south and 1,200 feet east of the northwest corner of Section 2, T. 17 S., R. 24 E., MDB&M; Latitude 36 degrees, 28 minutes, 48 seconds north and Longitude 119 degrees, 20 minutes, 37 seconds west; Monson Quadrangle.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 64 to 67 degrees F., and the soil temperature is always above 47 degrees F.
Depth to duripan: 20 to 40 inches.
Reaction: Slightly alkaline to moderately alkaline in the nonsaline-nonsodic phase and moderately alkaline to very strongly alkaline in the saline-sodic phase.
A Horizons--10YR 5/3, 5/4, 6/3 dry; 10YR 3/3, 3/4, 4/3 moist.
Clay content: 8 to 18 percent.
Organic Mater: 0 to 1 percent.
Carbonates: None to strongly effervescent.
Bw Horizons--10YR 5/3, 5/4, 6/3 dry; 10YR 3/3, 3/4, 4/3 moist.
Texture: Sandy loam, fine sandy loam or loam.
Clay content: 8 to 18 percent.
Organic Matter: 0 to 1 percent.
Carbonates: None to strongly effervescent.
2Bqkm horizon--10YR 5/4, 6/4 dry; 10YR 4/3, 4/4 moist.
Structure: Platy or massive.
Carbonates: None to violently effervescent.
2Bqk horizon--10YR 5/4, 6/3, 6/4 dry; 3/4, 4/3, 4/4 moist.
Carbonates: Slightly effervescent to violently effervescent.
Coarse fragments: 15 to 30 percent, dominantly pebble size duripan fragments.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Calgro soils are on terraces. Slopes are 0 to 2 percent. The soils formed in alluvium weathered from granitic rocks. Elevations are 250 to 480 feet. The climate is semiarid and has hot, dry summers and cool, moist winters. The average annual precipitation is 8 to 12 inches. The mean annual temperature is 62 degrees to 65 degrees F. The frost-free season is 250 to 300 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Akers(T), Colpien (T), Exeter, Grangeville, Tujunga and Youd series. Colpien and Grangeville soils lack duripans and have mollic epipedons. Exeter soils have argillic horizons and fine-loamy particle size families. Tujunga soils have a sandy particle size family. Akers soils lack duripans.
DRAINAGE AND PERMEABILITY: Moderately well drained; low or medium runoff; moderate permeability above the duripan, very slow in the duripan, and rapid below the duripan.
USE AND VEGETATION: This soil is used for irrigated cropland mainly to grow alfalfa, plums and grapes. It is also used for dairy and cattle production and building site development.
DISTRIBUTION AND EXTENT: San Joaquin Valley, California. The Calgro series is not extensive in MLRA-17.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Tulare County, California; Western Tulare County Soil Survey Area, 1999.
REMARKS: The soil name is taken from a local town. This soil is found in areas of irrigated cropland. Often these areas have been highly disturbed by farming activities. Most areas are mechanically plowed, ripped and chiseled to the surface of the duripan routinely. Also large amounts of organic matter, usually as manure, has been added to the soil, along with farm chemicals and soil amendments, and very large amounts of irrigation water over long periods of time. This has affected the carbonates, salinity, sodicity and the duripan. In most of the area the duripan is still present as described here, but in all areas it has been affected by the above mentioned disturbances. More study is needed to determine just exactly what the affects on the duripan are.
Some pedons are violently effervescent just above the duripan.
Diagnostic horizons and features recognized in this pedon:
1. Ochric epipedon--The zone from the surface to a depth of 7 inches (Ap1 and Ap2 horizons).
1.1 The thickness of the epipedon is less than one-third of the depth from the top of the epipedon to the upper boundary of the duripan.
2. Indurated Duripan--The zone from 25 to a depth of 33 inches (2Bqkm horizon).
3. Cambic horizon--The zone from 7 inches to a depth of 25 inches (Bw horizon).
Other features: Saline-sodic phases of this soil are recognized.