LOCATION NIULII HI
Established Series
Rev. RCH/HHS/MRK
06/2012
NIULII SERIES
The Niulii series consists of moderately deep, well drained soils that formed in material weathered from basic volcanic ash over pahoehoe lava. Niulii soils are on ash fields and have slopes of 6 to 100 percent. Mean annual rainfall is about 2286 millimeters (90 inches) and mean annual temperature is about 21 degress C. (70 degrees F.)
TAXONOMIC CLASS: Medial, ferrihydritic, isothermic Hydric Hapludands
TYPICAL PEDON: Niulii medial silty clay loam on a north facing, 7 percent slope, with grass cover. (Colors are for moist soil unless otherwise noted. All textures are "apparent field textures.")
Ap1--0 to 20 centimeters (0 to 8 inches); dark brown (10YR 3/3) medial silty clay loam; strong medium and fine subangular blocky structure; friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine vesicular pores; extremely acid (pH 4.0); abrupt smooth boundary. (15 to 25 centimeters {6 to 10 inches} thick)
Ap2--20 to 31 centimeters (8 to 12 inches); dark brown (7.5YR 3/4) medial silty clay loam; strong very fine and fine subangular blocky structure; friable, moderately sticky, moderately plastic; weakly smeary; many very fine and fine roots; many very fine and fine tubular pores; many gelatin-like coatings on faces of peds; very strongly acid (pH 5.0); clear smooth boundary. (8 to 15 centimeters {3 to 6 inches} thick)
Bw1--31 to 48 centimeters (12 to 19 inches); dark brown (7.5YR 3/3) medial silty clay loam; moderate very fine and fine subangular blocky structure; friable, moderately sticky, moderately plastic; weakly smeary; common very fine roots; many very fine and fine tubular pores; many gelatin-like coatings on faces of peds; strongly acid (pH 5.5); abrupt smooth boundary. (10 to 25 centimeters {4 to 10 inches} thick)
Bw2--48 to 76 centimeters (19 to 30 inches); dark brown (10YR 3/3) medial silty clay loam; moderate very fine and fine subangular blocky structure; friable, moderately sticky, moderately plastic; weakly smeary; few very fine roots; many very fine and fine tubular pores; moderately acid (pH 5.8); abrupt wavy boundary. (18 to 31 centimeters {7 to 12 inches} thick)
2R--76 centimeters {30 inches}; hard pahoehoe lava.
TYPE LOCATION: Island of Hawaii, Hawaii County, Hawaii; about 3 miles southeast of Kohala Post Office. Hawi Quadrangle - latitude 20 degrees 11 minutes 42 seconds north and 155 degrees 47 minutes 35 seconds west. {Old Hawaiian Datum)
RANGE IN CHARACTERISTICS:
Depth of bedrock: 51 to 102 centimeters (20 to 40 inches). Mean annual soil temperature: 18 to 22 degrees C. (65 to 72 degrees F.)
The Ap horizon Hue: 7.5YR or 10YR. Chroma: 3 or 4. Texture: medial silt loam or silty clay loam. Structure: granular or subangular blocky. Smeariness: nonsmeary to weakly smeary.
The Bw horizon Hue: 7.5YR or 10YR. Value: 3 or 4. Chroma: 3 or 4. Texture: medial silt loam or silty clay loam. Smeariness: weakly smeary to moderately smeary Soil dehydrates irreversibly into dark brown or black very hard sand- and silt-size particles.
COMPETING SERIES: There are no competing series. Similar soils include
Ainakea and
Paauhau series. Ainakea soils have an isohyperthermic temperature regime. Paauhau soils have weak subangular blocky structure in the upper part of the B horizon, are more than 40 inches deep, have an ustic soil moisture regime and have an isohyperthermic soil temperature regime.
GEOGRAPHIC SETTING: The Niulii soils are on middle elevation, windward mountain slopes at elevations of 335 to 610 meters (1,100 to 2,000 feet). These soils are on ash fields of gently sloping to steep lava flows and very steep valley slopes. Slope gradients range from 6 to 100. The soils formed in basic volcanic ash over pahoehoe lava. The mean annual rainfall ranges from 2032 to 2540 millimeters (80 to 100 inches). The mean annual temperature ranges from 18 to 22 degrees C. (65 to 72 degrees F.) The mean summer and mean winter soil temperatures differ by less than 6 degrees C. (11 degrees F.)
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Ainakea,
Kehena and
Kohala soils. Ainakea soils have strong structure in the B horizon and are nonsmeary. Kehena soils have common distinct redox concentrations in the A horizon. Kohala soils do not have andic soil properties.
DRAINAGE AND PERMEABILITY: Well drained; very low to high runoff; moderately rapid permeability.
USE AND VEGETATION: Niulii soils are used for grazing. Natural vegetation is hilograss (Paspalum conjugatum), guava (Psidium guajava), ohia lehua (Metrosideros polymorpha), and kikuyugrass (Pennisetum clandestinum).
DISTRIBUTION AND EXTENT: North Kohala District, Island of Hawaii. The series is inextensive with a total of about 3,000 acres. MLRA 164.
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: 0 to 31 centimeters (0 to 12 inches). Cambic horizon: 31 to 76 centimeters (12 to 30 inches).
Andic soil properties: 0 to 76 centimeters (0 to 30 inches) Lithic contact: at 76 centimeters (30 inches)
Edit log: 12/12/08 Competing series updated, SI units added, range in characteristics modified to semi tabular format and extensive revisions. MRK 2/2001 OSED scanned by SSQA. Last revised by state on 5/78.
National Cooperative Soil Survey
U.S.A.