LOCATION GOLDRIDGE CA

Established Series
Rev.DFW/JHR/DJE/ET
01/2023

GOLDRIDGE SERIES

The Goldridge series consists of deep and very deep, moderately well drained soils formed in material weathered from weakly consolidated sandstone. Goldridge soils are on rolling uplands with slopes of 2 to 50 percent. The mean annual precipitation is 45 inches and the mean annual temperature is 56 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, isomesic Typic Haplustults

TYPICAL PEDON: Goldridge fine sandy loam--on a south facing slope of 5 percent under apple trees at 350 feet elevation. (Colors are for dry soil unless otherwise stated).

Ap--0 to 7 inches; light brownish gray (10YR 6/2) fine sandy loam, yellowish brown (10YR 5/4) moist; single grain; soft, very friable, nonsticky and nonplastic; many very fine and fine roots; common very fine and fine tubular and interstitial pores; very strongly acid (pH 5.0); clear wavy boundary. (4 to 8 inches thick)

A1--7 to 20 inches; light brownish gray (10YR 6/2) fine sandy loam, dark yellowish brown (10YR 4/4) moist; massive; soft, friable, nonsticky and nonplastic; many very fine and fine, few medium and coarse roots; many fine and very fine interstitial and tubular pores; strongly acid (pH 5.2); clear wavy boundary. (8 to 15 inches thick)

A2--20 to 24 inches; light brownish gray (2.5Y 6/2) fine sandy loam, yellowish brown (10YR 5/6) moist; massive; slightly hard, friable, nonsticky and nonplastic; common very fine and fine roots; many fine and very fine tubular and interstitial pores; few thin clay films in pores; strongly acid (pH 5.1); clear wavy boundary. (2 to 5 inches thick)

Bt1--24 to 28 inches; light gray (10YR 7/2) fine sandy loam, yellowish brown (10YR 5/6) moist; massive; hard, firm, slightly sticky and slightly plastic; many very fine and fine roots; many fine and very fine interstitial and tubular pores; many thin clay films in pores; very strongly acid (pH 5.0); clear wavy boundary. (3 to 5 inches thick)

Bt2--28 to 41 inches; pale yellow (2.5Y 7/4) sandy clay loam with common fine distinct olive yellow (2.5Y 6/8) mottles, yellowish brown (10YR 5/6) moist with common fine distinct brown (7.5YR 5/4) mottles; massive; very hard, firm, sticky and plastic; common fine and few medium roots; many fine and very fine tubular pores; continuous thick clay films in pores; very strongly acid (pH 4.6); gradual irregular boundary. (10 to 15 inches thick)

Bt3--41 to 57 inches; mottled very pale brown (10YR 7/4) and light yellowish brown (10YR 6/4) sandy clay loam, olive yellow (2.5Y 6/6) moist with common gray (10YR 5/1) streaks; massive, very hard, firm, slightly sticky and slightly plastic; few fine roots; common fine and very fine tubular pores; continuous thick clay films in pores; extremely acid (pH 4.3); diffuse wavy boundary. (13 to 18 inches thick)

Bt4--57 to 73 inches; very pale brown (10YR 8/4) sandy clay loam with common fine distinct brownish yellow (10YR 6/8) mottles, yellow (2.5Y 7/6) moist with common coarse prominent gray (10YR 5/1) mottles; massive; hard, firm, nonsticky and slightly plastic; no roots observed; common very fine and fine tubular pores; continuous thick clay films in pores; very strongly acid (pH 4.5); diffuse wavy boundary. (0 to 20 inches thick)

C1--73 to 80 inches; pale yellow (2.5Y 8/4) fine sandy loam with common fine distinct yellow (2.5Y 7/6) mottles; yellow (2.5Y 7/6) moist with common medium prominent brown (10YR 5/3) mottles; massive, hard, firm, slightly sticky and slightly plastic; no roots observed; common fine and very fine tubular pores; continuous thick clay films in pores; very strongly acid (pH 4.5).

TYPE LOCATION: Sonoma County, California, 2 rows in from Elphic Road in the northeast corner NW 1/4, SW1/4, Section 11, T. 6 M., R. 9 W.

RANGE IN CHARACTERISTICS: The solum is 40 to 60 inches thick. Depth to weakly consolidated sandstone ranges from 40 to more than 60 inches. The mean annual soil temperature varies from 53 to 58 degrees F. The soil between the depths of 8 to 24 inches is moist in all parts from November to May. It is dry in some parts the rest of the year. Reaction is strongly or very strongly acid throughout.

The A horizon is 10YR 5/2, 5/3, 6/2, 6/3, 2.5Y 5/2, or 6/2. Moist colors are 10YR 4/4, 5/4, 5/6, 6/4, 6/5, 2.5Y 5/4 or 6/4. It is fine sandy loam with 10 to 20 percent clay.

The Bt horizon is 10YR 6/2, 6/4, 7/2, 7/4, 2.5Y 6/2, 6/4, 7/2 or 7/4. Moist colors are 10YR 5/6, 6/6, 7/6, 8/4, 2.5Y 6/6 or 7/6. It is sandy clay loam or clay loam with 25 to 35 percent clay. The upper part of the Bt horizon is fine sandy loam in some pedons. Base saturation is 20 to 35 percent.

The C horizon is 10YR 7/2, 7/4, 814, 2.4Y 7/2, 7/4, or 8/4. Moist colors are 2.5Y 7/6 or 7/4. It is sandy clay loam or fine sandy loam with 15 to 25 percent clay. Base saturation is 20 to 30 percent.

COMPETING SERIES: These are the Cotati and Sebastopol series in other families. Cotati soils have thermic soil temperatures. Sebastopol soils are clayey and have a xeric soil moisture regime.

GEOGRAPHIC SETTING: The Goldridge soils occur on rolling uplands. Slopes are 2 to 50 percent. Elevations range from 200 to 2,000 feet. The climate is subhumid mesothermal with warm dry summers and cool moist winters. Mean annual precipitation varies from 35 to 60 inches. Mean annual air temperature is 56 degrees F, mean January temperature is 45 degrees F, and mean July temperature is 70 degrees F. The frost-free season is 225 to 240 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Cotati and Sebastopol soils and the Steinbeck soils. Steinbeck soils have base saturation of 35 to 50 percent in the Bt horizon.

DRAINAGE AND PERMEABILITY: Moderately well drained; medium runoff; moderately slow permeability.

USE AND VEGETATION: Used mostly for apple orchards and timber. Native vegetation consists of redwood, Douglas fir, madrone and tanoak.

DISTRIBUTION AND EXTENT: Northern Coastal California. The series is moderately extensive.

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

SERIES ESTABLISHED: Sonoma County, California, 1915.

REMARKS: This is a classification change from fine-loamy, mixed, mesic Typic Haplustults to fine-loamy, mixed, isomesic Typic Haplustults. Change is based on soil-moisture temperature data gathered in adjoining soil survey areas.

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

This pedon was sampled by the SCS Riverside Soil Survey Laboratory in 1961. Pedon number is S61 Calif 49-6 and is described in the California SSIR No. 24 Pages 588 and 589.

Diagnostic horizons and features are as follows:

1. Ochric epipedon - 0 to 24 inches (Ap, A1, A2); ranges from 14 to 28 inches thick. Clay content by Riverside Lab is 9.5 in Ap, 12.2 in A1, and 12.5 in A2. Organic matter is 1.48 in Ap, 5.2 in A1 and decreases with depth--by Riverside Lab. B.S. is 33 to 38 percent by Riverside Lab.

2. Argillic horizon - 28 to 73 inches (Bt2, Bt3, Bt4); ranges from 23 to 53 inches thick. B.S. ranges from 22 to 32 percent by Riverside Lab. The textural control section is 28 to 48 inches, or the top 20 inches of the argilllic horizon. Clay content by Riverside Lab was 33.4 percent in the Bt2 28.9 percent in the Bt3, and 21.6 percent in the Bt4.

3. Mixed mineralogy--U.C. Davis data.

4. Soil temperature 53 to 58 degrees F--based on soil climate transect in Marin and Mendocino Counties on similar soils under similar vegetation.

5. Soil moisture in moisture control section.

J F M A M J J A S O N D

Dry in all parts 7/15-9/15
Moist in all parts 1/1---5/1
Soil is moist in all parts for 214 days and moist in some parts for 300 days.

OSED scanned by SSQA. Last revised by state on 3/87.

National Cooperative Soil Survey
U.S.A.