LOCATION STOHLMAN                CA

Established Series
Rev. PWV/DJL/WBS/TDC
01/2023

STOHLMAN SERIES

The Stohlman series consists of shallow, well drained soils that formed in residuum from extrusive igneous rock. Stohlman soils are on hills and have slopes of 9 to 50 percent. The mean annual precipitation is 17 inches and the mean annual temperature is 60 degrees

TAXONOMIC CLASS: Loamy, mixed, active, thermic Lithic Mollic Haploxeralfs

TYPICAL PEDON: Stohlman stony sandy loam - on a ridge top of about 9 percent slope under soft chess and wild oats at 265 feet elevation. (Colors are for dry soil unless otherwise stated. When described on October 2, 1980, the soil was dry throughout.)

A1--0 to 1 inch; light brownish gray (10YR 6/2) stony sandy loam, dark brown (10YR 3/3) moist; moderate fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine roots; few very fine interstitial pores; 1 percent boulders, 8 percent stones, 2 percent cobbles. 10 percent pebbles; slightly acid (pH 6.5); abrupt smooth boundary. (1 to 2 inches thick)

A2--1 to 7 inches; pale brown (10YR 6/3) stony sandy loam, dark brown (10YR 3/3) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine roots; few very fine interstitial pores; 1 percent boulders, 8 percent stones, 2 percent cobbles, 10 percent pebbles; slightly acid (pH 6.5); clear wavy boundary. (4 to 8 inches thick)

Bt1--7 to 15 inches; pale brown (10YR 6/3) gravelly sandy loam, dark brown (10YR 3/3) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few very fine roots; few very fine tubular and many very fine interstitial pores; many thin clay films in pores; 5 percent cobbles, 17 percent pebbles; slightly acid (pH 6.5); clear smooth boundary. (4 to 8 inches thick)

Bt2--15 to 16 inches; pale brown (10YR 6/3) gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few very fine roots; few very fine tubular and many very fine interstitial pores; many thin clay films on peds and in pores, and many thick clay films as bridges between mineral grains; 5 percent cobbles, 17 percent pebbles; slightly acid (pH 6.5); abrupt smooth boundary. (1 to 3 inches thick)

R--16 inches; yellowish brown (10YR 5/6) hard andesitic lahar bedrock.

TYPE LOCATION: Sutter County, California; Sutter Buttes area, approximately 0.4 mile north of Pass Road on test Butte Road, then northeast 0.5 mile on gas well road to ridgetop, then 200 feet west; 300 feet south and 2,200 feet east of the northwest corner of section 32. T. 16 N., R. 1 E.

RANGE IN CHARACTERISTICS: Depth to a lithic contact ranges from 10 to 20 inches. The mean annual soil temperature is 62 degrees to 66 degrees F. The soil temperature is above 47 degrees F the entire year. The 8 to 20 inch soil moisture control section is dry in all parts from April 15 to October 31 and moist in some or all parts from November 1 to April 15. The difference between mean summer and mean winter soil temperature is 30 degrees to 33 degrees F. Rock fragments range from 15 to 35 percent. It is slightly acid or neutral.

The A horizon has dry color of 10YR 6/2 or 6/3 and moist color of 10YR 3/2 or 3/3. Boulders range from 0 to 5 percent, stones or cobbles from 5 to 15 percent, and gravel from 10 to 25 percent. Organic matter content in the upper 4 inches is more than 1 percent.

The Bt horizon has dry color of 10YR 6/3 or 6/4 and moist color of 10YR 4/4 or 3/3. Clay content ranges from 10 to 18 percent with a 3 to 10 percent increase (absolute) over the A horizon. Stones range from 0 to 5 percent, cobbles from 5 to 10 percent, and gravel from 10 to 25 percent.

COMPETING SERIES: This is the Stonyford series and the Palls series in another family. Palls soils are 20 to 40 inches deep to a lithic contact. Stonyford soils have hues of 7.5YR or 5YR and a clay content of 25 to 35 percent.

GEOGRAPHIC SETTING: Stohlman soils are on hills. Slopes are 9 to 50 percent. The soils formed in residual material weathered from andesite or andesitic lahar (mudflow). Elevations are 75 to 1,500 feet. The climate is subhumid with hot dry summers and cool moist winters. Mean annual precipitation varies from 16 to 19 inches. Mean January temperature is 45 degrees F, mean July temperature is 77 degrees F, and mean annual temperature varies from 58 degrees to 62 degrees F. Frost-free season is 250 to 270 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Palls and the Ocraig and Olashes soils. Ocraig soils lack argillic horizons and are on mountains above Stohlman soils. Olashes soils have bedrock at depth greater than 60 inches and are on alluvial fans below Stohlman soils.

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

USE AND VEGETATION: This soil is used for rangeland. Characteristic vegetation is wild oats, soft chess, filaree, and scattered blue oak.

DISTRIBUTION AND EXTENT: Sutter Buttes area of the Sacramento Valley. Soils are not extensive.

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

SERIES ESTABLISHED: Sutter County, California 1983. Series name is from Stohlman Cemetery in the area.

REMARKS: The activity class was added to the classification in January of 2003. Competing series were not checked at that time. - ET

OSED scanned by SSQA. Last revised by state on 2/84.

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National Cooperative Soil Survey
U.S.A.