LOCATION LOADLINE CA

Established Series
MEB/KP
06/2011

LOADLINE SERIES

The Loadline series consists of shallow, excessively drained soils that formed in residuum and slope alluvium from dioritic igneous rock. Loadline soils are on side slopes of hills and mountains. Slopes range from 10 to 75 percent. The mean annual precipitation is about 355 millimeters (14 inches) and the mean annual temperature is about 21 degrees C (69 degrees F).

TAXONOMIC CLASS: Loamy, mixed, active, thermic, shallow Typic Argixerolls

TYPICAL PEDON: Loadline sandy loam in an area of dissected hills and mountains, on a northeast facing 45 percent slope under a cover of white sage at an elevation of 1472 feet (449 meters). (Colors are for dry soil unless otherwise noted).

Oi--0 to 0 inches, (0 to 1 cm); loose; abrupt wavy boundary. (0 to 3 cm)

A--0 to 2 inches, (1 to 6 cm); dark yellowish brown (10YR 4/4) broken face sandy loam, dark brown (10YR 3/3) broken face moist; 5 percent clay; weak fine subangular blocky structure; loose, very friable, nonsticky, slightly plastic; slightly acid, pH 6.7 by pH meter 1:1 water; abrupt wavy boundary. (5 to 16 cm)

Bt1--2 to 8 inches, (6 to 20 cm); brown (10YR 4/3) broken face fine sandy loam, dark brown (10YR 3/3) broken face moist; 9 percent clay; moderate medium subangular blocky structure; soft, very friable, nonsticky, nonplastic; common very fine roots; common fine tubular and common very fine tubular pores; faint clay films between sand grains and faint clay films on surfaces along root channels; slightly acid, pH 6.9 by pH meter 1:1 water; clear wavy boundary. (12 to 36 cm)

Bt2--8 to 15 inches, (20 to 38 cm); light yellowish brown (10YR 6/4) broken face sandy loam, brown (10YR 4/3) broken face moist; 10 percent clay; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky, slightly plastic; common fine roots and common very fine roots; common fine tubular and common very fine interstitial pores; faint clay films on surfaces along root channels and faint clay bridges between sand grains; 5 percent rounded 2 to 75 millimeter gravel; slightly acid, pH 6.9 by pH meter 1:1 water; clear wavy boundary. (0 to 18 cm)

Cr--15 to 18 inches, (38 to 45 cm) very hard, highly fractured (less than 10 cm apart), quartz-diorite porphyry; few very fine roots in fractures.

TYPE LOCATION: Santa Catalina Island, Los Angeles County, CA, in the Channel Islands Soil Survey Area 33 degrees North latitude, 20 minutes, 38 seconds and 118 degrees, 21 minutes, 34 seconds West longitude, NAD83. - U.S.G.S Quad: East Santa Catalina Island.

RANGE IN CHARACTERISTICS: The mean annual soil temperature is 15 to 22 degrees C. (59 to 71 degrees F.) The soil moisture control section is dry in all parts from about mid-June to mid-November and is usually moist the rest of the time.

The A horizon dry color is 10YR 7/2, 6/2, 6/3, 6/4. Moist color is 10YR 5/2, 4/2, 4/3, 4/4.
Textures are loamy sand, sandy loam, gravely sandy loam or sand.
Coarse fragments are usually absent but in some cases there may be 1 to 2 percent small gravels.

The Bt horizons dry color is 10YR 7/2, 6/2, 6/3, 6/4. Moist color is 10YR 5/2, 4/2, 4/3, 4/4.
Textures are sandy loam, loam, gravely loam, very gravely loam.
Coarse fragments are 5 to 60 percent small gravels.

COMPETING SERIES: There are no other series in this family.

GEOGRAPHIC SETTING: Loadline soils formed in dioritic rock on complex side slopes of interfluves of hills and mountains on islands. Slopes range from 10 to 75 percent. Elevations are from sea level to 1550 feet (0 to 472 meters). The climate is characterized by warm, dry summers and cool, moist winters with potential fog common all year. The mean annual precipitation is 13 to 24 inches (330 to 660 mm), the mean annual temperature is 61 to 73 degrees F. (16 to 23 degrees C.), and the frost free season is 355 to 365 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Oboship, Nauti, Flyer, Bosun, Marpol and Express. Oboship soils are found on predominately north aspects under continuous stands of oak and chaparral. Nauti soils are under sage and grass. Flyer soils are moderately deep. Express soils are coarse-loamy and predominately on the upper third slopes of interfluves. All these soils are found on side slopes of hills and mountains.

DRAINAGE AND PERMEABILITY: Excessively well drained; high runoff; rapid permeability.

USE AND VEGETATION: Wildlife habitat, recreation and building site development. Vegetation is predominately Coastal Sage Scrub and Non-native Scrub, Maritime Cactus Scrub and Coastal Bluff Scrub, Island Chaparral.

DISTRIBUTION AND EXTENT: Santa Catalina Island, Los Angeles County, California. The soil is not extensive. MLRA 20.

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

SERIES ESTABLISHED: Santa Catalina Island, Los Angeles County, California, 2006.

REMARKS: The series name is coined. Diagnostic horizons and features recognized in this pedon:

Mollic epipedon--The zone from the soil surface to a depth of about 8 inches (20 centimeters (A horizons).

Argillic endopedon--6 to 38 centimeters.

National Cooperative Soil Survey
U.S.A.