LOCATION KUKAIAU                 HI

Established Series
Rev. HHS/RCH/MRK
05/2012

KUKAIAU SERIES

The Kukaiau series consists of deep, well drained soils that formed in material weathered from basic volcanic ash over basalt. Kukaiau soils are on ash fields and have slopes of 0 to 70 percent. Mean annual rainfall is about 2159 millimeters (85 inches) and mean annual temperature is about 20 degrees C. (68 degrees F.)

TAXONOMIC CLASS: Hydrous, ferrihydritic, isothermic Typic Hydrudands

TYPICAL PEDON: Kukaiau medial silty clay loam, on a north facing, 16 percent slope in grass pasture at an elevation of 390 meters (1,280 feet). (Colors are for moist soil unless otherwise noted. All textures are "apparent field textures." ph measured with electrode in 1:1 soil to water. When described on August 13, 2008 the soil moist throughout.)

Ap--0 to 25 centimeters (0 to 10 inches); very dark grayish brown (10YR 3/2) medial silty clay loam; weak medium and fine granular structure; firm; slightly sticky and slightly plastic; weakly smeary; many very fine and fine roots; many very fine irregular pores; very strongly acid (pH 4.5); abrupt wavy boundary. (20 to 30 centimeters {8 to 12 inches} thick)

Bw1--25 to 41 centimeters (10 to 16 inches); dark brown (7.5YR 3/2) hydrous silty clay loam; weak medium and fine subangular blocky structure; friable; slightly sticky and slightly plastic; weakly smeary; many very fine and fine roots; many medium and fine tubular and interstitial pores,moderately acid (pH 5.6); abrupt wavy boundary. (15 to 25 centimeters {6 to 10 inches} thick)

Bw2--41 to 76 centimeters (16 to 30 inches); dark brown (7.5YR 3/3) hydrous silty clay loam; weak medium and fine subangular blocky structure; friable; slightly sticky and moderately plastic; weakly smeary; many very fine and fine roots; many medium and fine tubular and interstitial pores; slightly acid (pH 6.1); clear wavy boundary. (30 to 51 centimeters {12 to 20 inches} thick)

Bw3--76 to 96 centimeters (30 to 38 inches); dark brown (7.5YR 3/2) hydrous silty clay loam; moderate medium and fine subangular blocky structure; friable; slightly sticky and moderately plastic; weakly smeary; few very fine roots; many fine and very fine interstitial and tubular pores; 5 percent gravels; slightly acid (pH 6.2); abrupt wavy boundary. (15 to 25 centimeters {6 to 10 inches} thick)

2C/Bw4--96 to 127 centimeters (38 to 50 inches); dark brown (10YR 3/3) extremely gravelly hydrous silty clay loam; moderate medium and fine subangular blocky structure; friable; slightly sticky and moderately plastic; moderately smeary; few very fine roots; many medium and fine interstitial and tubular pores; 2C material consists of unconsolidated lava fragments; 50 percent gravel, 10 percent cobbles, 5 percent stones; slightly acid (pH 6.3).

2R--127 centimeters (50 inches); hard bedrock.

TYPE LOCATION: Island of Hawaii, Hawaii County, Hawaii; from Honokaa Town, at the junction of Plumeria St. and Highway 240, drive about 2.9 miles northwest on Highway 240. Pedon is located about 457 meters (1500 feet) upslope of highway at an elevation of 390 meters (1,280 feet). Kukuihaele Quadrangle; latitude 20 degrees 05 minutes 20.0 seconds north and longitude 155 degrees 30 minutes 28 seconds west (old Hawaiian datum.)

RANGE IN CHARACTERISTICS:
Depth to bedrock: 102 to 152 centimeters (40 to 60 inches). Mean annual soil temperature: 20 to 22 degrees C (68 to 72 degrees F.)

The A horizon Hue: 7.5YR or 10YR. Value: 2 or 3 Chroma: 2 or 3 Texture: Medial or hydrous, silty clay loam or silt loam. Structure: Weak to moderate, very fine to medium, granular or subangular blocky.
Smeariness: Weakly to moderately smeary

The Bw horizon Hue: 5YR to 10YR. Value: 2 or 3 Chroma: 3 to 4 Texture: Medial or hydrous, silty clay loam or silt loam. Structure: Weak to moderate, very fine to medium, subangular blocky.
Smeariness: Weakly to moderately smeary
The Bw horizon is more smeary as elevation and rainfall increase.
The Bw horizon dehydrates irreversibly into dark brown or black, very hard sand- and silt-size aggregates.

COMPETING SERIES: These are the Alapai, Honaunau, Honuapo, Kailua, Kealakekua and Makaala series. Alapai soils are greater than 152 centimeters (60 inches) deep. Honaunau soils are 50 to 102 centimeters (20 to 40 inches) deep over bedrock and are moderately well drained. Honuapo, Kealakekua and Makaala soils are 50 to 102 centimeters (20 to 40 inches) deep over bedrock. Kailua soils have silty clay texture from the surface to 69 centimeters (27 inches).

GEOGRAPHIC SETTING: Kukaiau soils are on mid elevation, windward slopes of Muana Kea shield volcano at elevations from 335 to 457 meters (1,100 to 1,500 feet). These soils are on all hillslope positions of gently sloping to steep ash fields and gulches on lava flows. Slope gradients range from 0 to 70 percent. The soils formed in basic volcanic ash over basaltic lava. The mean annual rainfall ranges from 1,778 to 2,540 millimeters (70 to 100 inches), with most of the rainfall occurring from October through April. The mean annual temperature ranges from 18 to 22 degrees C. (64 to 72 degrees F.) The mean summer soil temperature and the mean winter soil temperature differ by less than 6 degrees C. (11 degrees F.)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Honokaa and Paauhau series. Honokaa soils have strong subangular blocky structure in the B horizon. Paauhau soils have an isohyperthermic soil temperature regime.

DRAINAGE AND PERMEABILITY: Well drained; medium to high runoff; moderate permeability.

USE AND VEGETATION: These soils are used for grazing and growing Eucalyptus trees. The natural vegetation is hilograss (Paspalum conjugatum), kikuyugrass (Pennisetum clandestinum) and common guava (Psidium guajava).

DISTRIBUTION AND EXTENT: Hamakua District, Island of Hawaii. These soils are inextensive. MLRA 159A.

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

SERIES ESTABLISHED: Soil Survey, Territory of Hawaii, 1949.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Umbric epipedon - from the surface to 25 centimeters (0 to 10 inches) (Ap horizon).
Andic soil properties - from 0 to 127 centimeters (0 to 50 inches) (All horizons).
Cambic Horizon - from 25 to 127 centimeters (10 to 50 inches) (Bw and 2C/Bw horizons).
Lithic contact - at 127 centimeters (50 inches) (R horizon).

ADDITIONAL DATA: NASIS Pedon User ID 09HI603005.

Edit Log: OSED scanned by SSQA. Last revised by state on 5/78.
10/29/09 Range in characteristics, competing series and geographic setting updated. Other minor edits. MRK.

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National Cooperative Soil Survey
U.S.A.