LOCATION MONORIDGE CA
Established Series
Rev: PGN-KDA-CEJ
03/2023
MONORIDGE SERIES
The Monoridge series consists of moderately deep, somewhat excessively drained, sandy textured soils on escarpments on mountains. These soils formed in colluvial material weathered from marine sandstone. Slope is 30 to 65 percent. The mean annual precipitation is about 11 inches and the mean annual temperature is about 62 degrees F.
TAXONOMIC CLASS: Mixed, thermic Typic Xeropsamments
TYPICAL PEDON: Monoridge fine sand - on a south-facing slope of 52 percent under red brome, soft chess, snakeweed, California buckwheat and other annual grasses and shrubs. The elevation is 1,180 feet. (Colors are for dry soil unless otherwise stated. When described April 17, 1984 the soil was slightly moist below 14 inches).
A--0 to 7 inches; pale brown (10YR 6/3) fine sand, brown (10YR 4/3) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine roots; few fine tubular and interstitial pores; slightly effervescent, carbonates disseminated; slightly alkaline (pH 7.7); clear smooth boundary. (5 to 10 inches thick)
Cy1--7 to 14 inches; very pale brown (10YR 7/3) sand, yellowish brown (10YR 5/4) moist; single grain; soft, very friable, nonsticky and nonplastic; common very fine roots; few very fine interstitial pores; strongly effervescent, carbonates disseminated; few soft masses of gypsum; moderately alkaline (pH 8.2); clear wavy boundary. (6 to 12 inches thick)
Cy2--14 to 18 inches; very pale brown (10YR 7/4) sand, yellowish brown (10YR 5/4) moist; few fine distinct strong brown (7.5YR 5/6) relict mottles, strong brown (7.5YR 4/6), moist; massive; soft, very friable, nonsticky and nonplastic; few very fine roots; few very fine interstitial pores; slightly effervescent, carbonates disseminated; few soft masses of gypsum; slightly alkaline (pH 7.8); clear wavy boundary. (3 to 8 inches thick)
Cy3--18 to 25 inches; light yellowish brown (10YR 6/4) sand, dark yellowish brown (10YR 4/4) moist; few fine distinct strong brown (7.5YR 5/6) relict mottles, strong brown (7.5YR 4/6) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine roots; few fine interstitial pores; slightly effervescent, carbonates disseminated; few soft masses of gypsum; slightly alkaline (pH 7.8); clear wavy boundary. (6 to 10 inches thick).
Cr--25 to 29 inches; soft sandstone
TYPE LOCATION: Fresno County, California; approximately 150 feet north of the bottom of the creek, 2.5 miles southwest of Interstate 5 on Monocline Ridge; 1,800 feet east and 1,800 feet north of the southwest section corner of section 16, T. 16 S., R. 13 E., MDB&M; Latitude 36 degrees, 32 minutes, 13 seconds north and Longitude 120 degrees, 33 minutes, 42 seconds west; USGS Monocline Ridge Topographic Quadrangle, NAD 27.
RANGE IN CHARACTERISTICS: Depth to a paralithic contact of soft sandstone is 20 to 40 inches. The moisture control section of 14 to 40 inches is moist from February 15 to April 15 and dry from June 1 to October 15 in most years. The soil temperature is above 47 degrees F from January 15 to December 15. The mean annual soil temperature is 63 to 68 degrees F.
The A horizon has color of 10YR 6/2, 6/3, 7/1; 2.5Y 6/2 or 7/2. Moist color is 10YR 4/2, 4/3, 5/3; 2.5Y 4/2 or 4/4. Organic matter is 0.3 to 0.5 percent. Clay content is 2 to 7 percent. Calcium carbonate equivalent is 0 to 2 percent. Gypsum content is 1 to 3 percent. Electrical conductivity is 0 to 2 decisiemens per meter. Sodium adsorption ratio is 1 to 3 percent. Reaction is slightly alkaline or moderately alkaline.
The Cy horizon has color of 10YR 6/2, 6/4, 7/3, 7/4 or 2.5Y 6/4. Moist color is 10YR 4/4, 5/4, 7/2; 2.5Y 4/2 or 4/4. Relict mottles are not associated with present wetness. Clay content is 2 to 10 percent. Calcium carbonate equivalent is 1 to 2 percent. Depth to a gypsic horizon with gypsum content of 5 to 10 percent is 5 to 10 inches. Electrical conductivity is 2 to 4 decisiemens per meter. Sodium adsorption ratio is 1 to 3 percent. Reaction is slightly alkaline or moderately alkaline.
COMPETING SERIES: These are the
Arnold,
Briones,
Calhi,
Corralitos,
Delhi,
Monvero and
Tujunga soils. Arnold soils (MLRA 15, 20), on hills and uplands, have a paralithic contact at a depth of 40 to 60 inches. Briones soils (MLRA 15), on uplands, have slightly acid to strongly acid reaction and do not have effervescence. Calhi soils (MLRA 17), on short rolling dune-like slopes, are deeper than 60 inches and have moderately alkaline to very strongly alkaline reaction. Corralitos soils (MLRA 14, 19), on alluvial fans, are deeper than 60 inches have strongly acid to neutral reaction and do not have effervescence. Delhi soils (MLRA 17, 19), on flood plains, alluvial fans and terraces, are deeper than 60 inches and do not have effervescence. Monvero soils (MLRA 15), on dune fields on mountains, are deeper than 60 inches and have slopes less than 30 percent. Tujunga soils (MLRA 14, 17, 18, 19, 29, 30), on alluvial fans and flood plains, are deeper than 60 inches and have slightly acid to slightly alkaline reaction.
GEOGRAPHIC SETTING: Monoridge soils are on escarpments on mountains. Slope is 30 to 65 percent. Elevation is 718 to 3,390 feet. These soils formed in colluvial material weathered commonly from marine sandstone of the Vaqueros formation. The climate is semiarid with hot dry summers and cool moist winters. The mean annual precipitation is 9 to 13 inches. Mean January temperature is 46 degrees F; mean July temperature is 81 degrees F; mean annual temperature is 59 to 62 degrees F. The frost-free season is 210 to 260 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing
Monvero soils and the
Belgarra, and
Exclose soils. Belgarra soils are on erosional fan remnants on mountains, are deep and have a fine particle-size control section. Exclose soils are on mountains, are deep and have a fine-loamy particle-size control section.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; low runoff; rapid permeability.
USE AND VEGETATION: These soils are used for livestock grazing and wildlife habitat. The vegetation is red brome, soft chess, narrowleaf goldenbush, California buckwheat, allscale saltbush, and other annual grasses and shrubs.
DISTRIBUTION AND EXTENT: Eastern edge of the Diablo Range, near Monocline Ridge in the California Coast Ranges. They are not extensive. MLRA 15.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Fresno County, California, 2002. Coined name after nearby Monocline Ridge.
REMARKS: These soils were formerly mapped as Rough Broken Land in the unpublished report, Soil Survey of Western Fresno, 1967. They are being differentiated by being classified and mapped. Consideration should be given to the possibility of requesting that a gypsic subgroup be added to the great group of Xeropsamments in Soil Taxonomy. Monoridge soil does not have a cambic horizon because it does not have texture of very fine sand, loamy fine sand, or finer.
ADDITIONAL DATA: KSSL lab data pedon sample number S84CA019-001 (1227-1228) for the typical pedon.
National Cooperative Soil Survey
U.S.A.