LOCATION AGER CA+IDEstablished Series
TAXONOMIC CLASS: Very-fine, smectitic, mesic Chromic Haploxererts
TYPICAL PEDON: Ager clay, range. (Colors are for dry soil unless otherwise noted.)
A1--0 to 2 inches; grayish brown (10YR 5/2) clay, light brownish gray (10YR 6/2) moist; strong very fine granular structure; loose, friable, very sticky and very plastic; few very fine roots; many very fine interstitial pores; cracks 4 cm wide; mildly alkaline (pH 7.5); abrupt smooth boundary. (1 to 2 inches thick)
A2--2 to 7 inches; grayish brown (10YR 5/2, dry and moist) clay; weak medium platy and strong very coarse prismatic structure; very hard, friable, sticky and very plastic; few very fine, fine and medium roots, mostly exped; common very fine tubular pores; cracks 4 cm wide; mildly alkaline (pH 7.5); clear smooth boundary. (4 to 7 inches thick)
Bssk1--7 to 25 inches; grayish brown (10YR 5/2, dry and moist) clay; strong very coarse prismatic parting to strong very coarse and coarse angular blocky structure; extremely hard, friable, sticky and very plastic; few very fine, fine and medium roots, mostly exped; few very fine tubular pores; cracks 3 cm wide; common intersecting slickensides; slightly effervescent, lime segregated in fine irregular soft bodies; mildly alkaline (pH 7.5); gradual wavy boundary. (16 to 20 inches thick)
Bssk2--25 to 33 inches; dark grayish brown (10YR 4/2) clay, dark brown (10YR 4/3) moist; strong very coarse angular blocky structure; extremely hard, friable, sticky and very plastic; few very fine, fine, medium and coarse roots, mostly exped; few very fine and fine tubular pores; many intersecting slickensides; cracks 1 cm wide; strongly effervescent, lime segregated in fine irregular soft bodies; common fine white (10YR 8/1) lime accumulations; moderately alkaline (pH 8.0); gradual wavy boundary. (6 to 10 inches thick)
Bssk3--33 to 39 inches; brown (10YR 5/3) clay, dark brown (10YR 4/3) moist; moderate fine prismatic structure parting to weak fine and medium angular blocky structure; extremely hard, friable, sticky and very plastic; few very fine, fine and medium roots, mostly exped; common very fine tubular pores; common intersecting slickensides; strongly effervescent, lime segregated as fine irregular filaments and soft bodies; many fine white (10YR 8/1) lime accumulations; moderately alkaline (pH 8.0); abrupt wavy boundary. (5 to 7 inches thick)
Bk--39 to 47 inches; pale brown (10YR 6/3) clay loam, dark brown (10YR 4/3) moist; moderate medium prismatic parting to moderate coarse angular blocky structure; very hard, friable, sticky and plastic; few very fine and fine roots; common very fine tubular and interstitial pores; violently effervescent, lime segregated as fine irregular seams; many fine white (10YR 8/1) lime accumulations; moderately alkaline (pH 8.0); abrupt smooth boundary. (7 to 9 inches thick)
B--47 to 53 inches; light gray (10YR 7/1, dry and moist) loam; common fine pale brown (10YR 6/3) mottles; massive; very hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; many very fine and few fine tubular and few very fine interstitial pores; violently effervescent with disseminated lime; moderately alkaline (pH 8.0); gradual smooth boundary. (5 to 8 inches thick)
Cr1--53 to 64 inches; light yellowish brown (10YR 6/4) soft siltstone that crushes to silt loam; very hard, friable; no roots; very weakly cemented; strongly effervescent with lime segregated in fine irregular shaped filaments; moderately alkaline (pH 8.0); gradual smooth boundary. (10 to 14 inches thick)
Cr2--64 to 78 inches; light yellowish brown (10YR 6/4) soft mudstone that crushes to silty clay loam; extremely hard, firm; slightly effervescent with lime segregated in fine irregular filaments; moderately alkaline (pH 8.0)
TYPE LOCATION: Modoc County, California; about 2 miles northeast of Canby; 1,500 feet south and 1,300 feet west of the NW 1/4 corner section 20, T. 42 N., R. 10 E.
RANGE IN CHARACTERISTICS: Depth to a paralithic contact of mudstone or siltstone lake deposits is 40 to 60 inches. Depth to secondary carbonates is less than 10 inches. The mean annual soil temperature is about 50 to 55 F. The soil between depths of 4 to 12 inches is usually dry all of the time from July 15 until October 15 and is moist in some or all parts all the rest of the year. The soil has cracks that open and close once each year, remain open during the period of July through October and remain closed the rest of the year. Few to many intersecting slickensides occur in the lower A horizon. Rock fragments range to 25 percent of the surface horizon and occur just on the surface and consist mostly of rounded basalt cobbles. The control section usually has 60 to 70 percent clay and ranges to 75 percent clay in some pedons.
The A horizon is pale brown and brown to olive or dark grayish brown dry and moist (10YR or 5Y 6/3, 6/2, 5/3, 5/2, 4/3, 4/2; 2.5Y 6/2; 5/2, 4/2). When the dry value is 4 or 5, the moist value is 4 or more. The A horizon is clay or silty clay and has strong granular structure in the surface few inches and strong angular blocky or prismatic structure in the lower part. It increases in pH and in carbonates as depth increases.
The Bk horizon is light gray, pale brown, or light brownish gray in 10YR or 2.5Y hue. The Cr horizon is soft siltstone or mudstone that crushes to silt loam, loam, silty clay loam, or clay loam and has rock structure.
COMPETING SERIES: These are the Beirman (T) and Tunnison (T) series. Bierman soils are 10 to 20 inches deep to secondary carbonates. Tunnison soils are 20 to 40 inches deep to a lithic contact.
GEOGRAPHIC SETTING: Ager soils are on lake terraces and escarpments of lake deposits. They formed in lake deposits of the pleistocene age at elevations of 4,000 to 5,000 feet. The climate is cool semiarid mesothermal with warm dry summers and cold moist winters. Mean annual precipitation is 10 to 14 inches. Average January temperature is 28 F; average July temperature is 68 F; mean annual temperature is 47 to 49 F. The frost-free season is 70 to 90 days. In southwestern Idaho elevation is 2,300 to 3,000 feet and the frost-free season is 120 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Barnard, Bieber, Casuse, Daphnedale, Delma and Simpson soils. Barnard and Bieber soils are underlain by duripans. Casuse and Delma soils have mollic epipedons, argillic horizons, and are less than 20 inches deep to a paralithic contact. Daphnedale soils have mollic epipedons, argillic horizons and have frigid soil temperature regimes. Simpson soils have mollic epipedons, argillic horizons and have formed in loamy and sandy lacustrine lake deposits.
DRAINAGE AND PERMEABILITY: Well-drained; slow to rapid runoff; slow or very slow permeability.
USE AND VEGETATION: The steeper slopes are used as rangeland. The more gently sloping soils are used for dry land crops. Vegetation is scattered trees, shrubs and grass, mainly western juniper, big sagebrush, rabbitbrush, cheatgrass, medusahead and thistles. In some places there are small patches of bare granular soil.
DISTRIBUTION AND EXTENT: Northeastern California, and possibly southeastern Oregon and Nevada. The soils are inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Shasta Valley, Siskiyou County, California, 1943.
REMARKS: Diagnostic horizons and features recognized in this pedon are: Ochric epipedon: 0 to 7 inches (A1, A2). Slickensides: the zone from 7 to 39 inches (Bssk1, Bssk2, Bssk3).
ADDITIONAL DATA: Riverside Laboratory pedon S72 Calif-25-22, not yet published.
Series reclassified on September, 1994. Competing series not reviewed at that time.