LOCATION ALDI                    CA

Established Series
Rev. FOS-DJE-TKK
03/2023

ALDI SERIES

The Aldi series consists of shallow, well drained soils formed in material weathered from volcanic rock. Aldi soils are on mountains and have slopes of 2 to 75 percent. The mean annual precipitation is about 640 mm and the mean annual air temperature is about 7 C.

TAXONOMIC CLASS: Clayey, smectitic, frigid Lithic Ultic Argixerolls

TYPICAL PEDON: Aldi cobbly loam on an east draining valley floor of 2 percent under scattered bitter brush, annual and perennial grasses at 1,758 meters elevation. (Colors are for dry soil unless otherwise stated. When described on April 5, 1977, the soil was moist throughout).

O--0 to 1 cm; fresh and slightly decomposed grass and bitterbrush litter.

A1--1 to 21 cm; brown (10YR 4/3) cobbly loam, dark reddish brown (5YR 3/2) moist; weak fine granular structure; slightly hard, friable, nonsticky and slightly plastic; common very fine and fine interstitial pores; 5 percent pebbles; 10 percent cobbles; slightly acid (pH 6.5); clear wavy boundary. (18 to 26 cm thick)

Bt--21 to 46 cm; brown (7.5YR 5/4) clay, loam, brown (7.5YR 4/4) moist; moderate medium and coarse angular blocky structure; hard, firm sticky and plastic; few very fine roots; common fine tubular and interstitial pores; many moderately thick clay films on peds and in pores; 5 percent gravel; neutral (pH 7.0); diffuse irregular boundary. (15 to 25 cm thick)

R--46 to 75 cm; fractured andesite or basalt (some cracks up to 10 cm apart).

TYPICAL LOCATION: Nevada County, Tahoe National Forest, California; about 1.6 km southeast of Woodchopper Spring near the center of sec. 19, T. 18 N., R. 17 E., MDB&M. WGS84 latitude 39.39587, longitude -120.13846. UTM Zone 10, 746419 meters east, 4364616 meters north, WGS84.

RANGE IN CHARACTERISTICS: The thickness of the solum and depth to a lithic contact is 10 to 50 cm. The thickness of the epipedon is 18 to 36 cm. The soil between a depth of about 15 to 50 cm is usually dry all of the time from July 15 until November 1 and is moist in some or all parts the rest of the year. The mean annual soil temperature is about 6 to 8 C. Base saturation is 50 to 75 percent throughout the argillic horizon.

The A horizon has dry color of 10YR 3/3; 4/3; 5/2 and 5/3. Moist colors are 5YR 3/2; 7.5YR 3/2; 10YR, 2/2 and 3/2. It is or clay loam and has 5 to 10 percent gravel and 10 to 20 percent cobbles. It is slightly acid to neutral.

The Bt horizon has dry color of 7.5YR 4/4, 5/4; and 10YR 5/3. Moist colors are 7.5YR 4/4 or 10YR 3/4. Texture is clay loam or clay and averages 35 to 45 percent clay. Absolute increase in clay from the A horizon is less than 20 percent. It may be gravelly or cobbly and ranges from 5 to 15 percent gravel, and 0 to 20 percent cobbles. Total rock fragments average less than 35 percent. It is moderately acid to neutral.

COMPETING SERIES: This is the Alding series. Alding soils have a moisture control section which is dry in all parts for only 60 to 88 days between mid-July and late September. In addition Alding soils lack colors of 7.5YR in the Bt horizon and have moist chromas of less than 4. Alding soils also are formed in colluvium.

GEOGRAPHIC SETTING: Aldi soils are on gently sloping valley floors and moderately steep to steep mountainside slopes at elevations of 1,515 to 1,970 meters. Slope ranges from 2 to 75 percent. These soils formed in material weathered from basic volcanic flows, breccias and agglomerates. The mean annual precipitation varies from 380 to 890 mm and the mean annual air temperature varies from 6 to 8 C. Mean January temperature is about -3 C and mean July temperature is about 16 C. The frost-free season is less than 30 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Franktown and Kyburz soils. Franktown soils have more than 35 percent rock fragments in the control section and do not have an argillic horizon. Kyburz soils are over 40 inches deep.

DRAINAGE AND PERMEABILITY: Well drained; medium runoff; slow permeability.

USE OF VEGETATION: Used for unimproved range wildlife habitat, watershed and recreation. Principal species are bitterbrush, sagebrush, annual and perennial grasses.

DISTRIBUTION AND EXTENT: Northwestern part of Sierra Nevada Range of California. The soils are moderately extensive.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Davis, California

SERIES PROPOSED: Nevada County (Tahoe National Forest Area), California, 1981.

REMARKS:

Previously revised by the state on 6/81.

This soil was classified using the 13th edition of the Keys to Soil Taxonomy.

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National Cooperative Soil Survey
U.S.A.