LOCATION VIZCAPOINT CA

Established Series
RJ/DCE/CEJ/GML/ET
04/2019

VIZCAPOINT SERIES

The Vizcapoint series consists of very deep, well drained soils formed in alluvium material derived mostly from sedimentary rock sources. Vizcapoint soils are on marine terraces and have slopes of 2 to 20 percent. The mean annual precipitation is about 280 millimeters (11 inches) and the mean annual temperature is about 16 degrees C (61 degrees F).

TAXONOMIC CLASS: Fine, smectitic, isothermic Typic Natrustalfs

TYPICAL PEDON: Vizcapoint sandy loam - on a slightly west facing slope of 3 percent under a cover of slender oats, soft chess, Mediterranean barley and burclover at 1510 meters (460 feet) elevation. (Colors are for dry soil unless otherwise stated. When described on October 4, 1984, the soil was moist below a depth of 58 centimeters (23 inches).)

E--0 to 23 centimeters (0 to 9 inches); pale brown (10YR 6/3) sandy loam, brown (10YR 4/3) moist; massive; hard, friable, nonsticky and nonplastic; many very fine and common fine roots; many very fine interstitial pores; neutral (pH 6.8); abrupt wavy boundary. (15 to 25 centimeters; 6 to 10 inches thick)

Btn1--23 to 51 centimeters (9 to 20 inches); light brownish gray (10YR 6/2) clay, dark grayish brown (10YR 4/2) moist; strong coarse and very coarse prismatic structure; cracks are filled with sand and coat the prisms; extremely hard, firm, very sticky and very plastic; common very fine and few fine roots; many very fine tubular pores; common pressure faces; moderately alkaline (pH 8.0); gradual smooth boundary. (25 to 36 centimeters; 10 to 14 inches thick)

Btn2--51 to 74 centimeters (20 to 29 inches); light brownish gray (10YR 6/2) clay, dark grayish brown (10YR 4/2) moist, with iron stains brownish yellow (10YR 6/6), dark yellowish brown (10YR 4/6) moist; strong coarse and very coarse prismatic parting to strong coarse and very coarse angular blocky structure; some cracks are filled with sand; extremely hard, firm, very sticky and very plastic; common very fine roots; common very fine tubular pores; common pressure faces; moderately alkaline (pH 8.0); gradual wavy boundary. (20 to 30 centimeters; 8 to 12 inches thick)

Btn3--74 to 119 centimeters (29 to 47 inches); light brownish gray (2.5Y 6/2) clay, dark grayish brown (2.5Y 4/2) moist; strong coarse and very coarse angular blocky structure; sand coatings on the peds and in cracks; extremely hard, firm, very sticky and very plastic; few very fine roots; common very fine tubular pores; few pressure faces; moderately alkaline (pH 8.0); gradual wavy boundary. (25 to 56 centimeters; 10 to 22 inches thick)

C--119 to 152 centimeters (47 to 60 inches); light brownish gray (10YR 6/2) clay, dark grayish brown (10YR 4/2) moist; strong medium and coarse angular blocky structure; some peds have sand coatings; extremely hard, firm, very sticky and very plastic; few very fine roots; common very fine tubular pores; moderately alkaline (pH 8.0)

TYPE LOCATION: San Nicolas Island, Ventura County, California; site is located at the northwest end of the landing airfield, then about 90 meters (300 feet) northwest of the paved road that goes to the beach; 33.2503111 degrees latitude, -119.4716139 degrees longitude; UTM Zone 11, 3681761.23n, 269737.59e; U.S.G.S. Quad Name: San Nicolas Island.

RANGE IN CHARACTERISTICS: The solum ranges from 102 to 127 centimeters (40 to 50 inches) in thickness. The mean annual soil temperature is about 17 degrees C (62.6 degrees F), and the difference between the mean summer and the mean winter temperature is about 5 degrees C (9 degrees F). The soil between the depths of 25 to 46 centimeters (10 to 18 inches) is moist in all parts of the moisture control section for about 60 to 75 days, from about January to early or mid-March and is dry in all parts from about May or June to about November. The soil temperature is always above 8 degrees C (47 degrees F). The moisture regime is ustic bordering aridic. When dry, the subsoil soil develops cracks that are less than 1 cm wide and are 8 to 15 centimeters (3 to 6 inches) apart at 50 centimeters (20 inches) or more in depth. The soil contains about 0 to 10 percent ferruginous subrounded hard nodules in the profile. Some pedons have coatings of organic matter or sand on the faces of the prisms or in the cracks of the Btn horizons. The soils are neutral to moderately alkaline. Some pedons have finely disseminated calcium carbonate or calcium carbonate is segregated in fine or medium seams, filaments or threads. Channeled and eroded phases are recognized in the series.

The E horizon has dry color of 10YR 6/2, 6/3, 7/2, or 7/3. Moist colors are 10YR 4/2, 4/3, 5/2, or 5/3. Clay content is 8 to 12 percent. The clay content between the E and the Bt horizons is greater than 25 percent absolute within 1 inch. ESP ranges from 5 to 10, and the electrical conductivity is less than 2.

The Btn horizon has dry color of 10YR 5/2, 6/2, 6/3, 7/2, 7/3; 2.5Y 5/2 or 6/2. Moist colors are 10YR 3/2, 4/2, 4/3, 5/2, 5/3, 2.5Y 3/2 or 4/2. Clay content is 40 to 60 percent. ESP ranges from 15 to 40, and the electrical conductivity is 2 to 8.

The C horizon is 10YR 6/2, 6/3, or 6/4; 2.5Y 6/2 or 6/4, moist color is 10YR 4/2, 4/3, or 4/4, 2.5Y 4/2, or 4/4. It is clay and clay loam. Clay content is 35 to 50 percent. ESP ranges from 5 to 20, and the electrical conductivity is 2 to 8.

Some pedons do not have C horizons or have an overwashed layer over the E horizon, or have an A horizon.

COMPETING SERIES: This is the Eelcove series. Eelcove soils formed in fine alluvium from mixed rock sources and are on San Clemente Island marine terraces.

GEOGRAPHIC SETTING: The Vizcapoint soils are on marine terraces and have slopes of 2 to 20 percent. The soils formed in alluvium weathered mostly from sedimentary rock sources. Elevation ranges from 10 to 265 meters (30 to 870 feet). The climate is subhumid with warm dry summers and cool moist winters. Commonly fog and low clouds occur during the summer months and the relative humidity is 60 to 80 percent. Mean annual precipitation is about 280 millimeters (11 inches). Mean January temperature is about 12.2 degrees C (54 degrees F), mean July temperature is about 17.8 degrees C (64 degrees F). The mean annual temperature is about 16 degrees C (61 degrees F). Frost-free season is about 365 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Jehemy, Nicolas and Olf soils. Jehemy and Nicolas soils do not have argillic horizons. Jehemy soils are located on hills and marine terraces. Nicolas soils are located on dunes. The Olf series are 51 to 102 centimeters (20 to 40 inches) to soft bedrock and are located on marine terraces.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained, slow to rapid runoff, very low saturated hydraulic conductivity.

USE AND VEGETATION: Used mainly for military maneuvers and wildlife habitat. Vegetation is mainly slender oats, soft chess, Mediterranean barley, red brome and bur clover.

DISTRIBUTION AND EXTENT: San Nicolas Island, Ventura County, California. The soils are not extensive.

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

SERIES ESTABLISHED: Channel Islands Soil Survey Area, San Nicolas Island Part, Ventura County, California, 1985. The name was coined from Vizcaino Point.

REMARKS:

Diagnostic horizons and features recognized in this pedon are:
Natric horizon - the zone from a depth of 23 to 119 centimeters (9 to 47 inches). (Bt1, Bt2, Bt3).

Ustic bordering aridic moisture regime: Moist in all parts of the control section for 60 to 75 days after December 21st.

This pedon has samples SCA84-111-004-8 thru 10 from the Soil Survey National Laboratory at Lincoln, Nebraska.

OSD revised during correlation of the San Nicolas Island Interim Report in 2018.

ADDDITIONAL DATA:

NASIS USER PEDON ID: 1985CA111005
Classified using the Twelfth Edition Keys to Soil Taxonomy (2014)

National Cooperative Soil Survey
U.S.A.