LOCATION KUNIA HIEstablished Series
TAXONOMIC CLASS: Fine, parasesquic, isohyperthermic Oxic Dystrustepts
TYPICAL PEDON: Kunia silty clay - pineapple. (Colors are for moist soil unless otherwise noted. Textures are "apparent field textures.")
Ap1--0 to 3 inches; dark reddish brown (5YR 2/2) silty clay, dark reddish brown (5YR 3/3) dry; moderate fine and very fine granular structure; hard, friable, sticky and plastic; many roots; many fine interstitial pores; strong effervescence with hydrogen peroxide; extremely acid (pH 4.3); clear wavy boundary. (2 to 9 inches thick)
Ap2--3 to 22 inches; same color and texture as Ap1 horizon; weak fine and medium subangular blocky structure; hard, firm, sticky and plastic; compacted by tillage; few fine roots; common very fine tubular and interstitial pores; few fine and very fine black concretions; few charcoal specks; strong effervescence with hydrogen peroxide; extremely acid (pH 4.2); abrupt smooth boundary. (9 to 19 inches thick)
B1--22 to 29 inches; dark reddish brown (2.5YR 2/4) silty clay, dark reddish brown (2.5YR 3/4) dry; weak fine and medium subangular blocky structure; slightly hard, firm, sticky and plastic; common very fine tubular pores; few patchy pressure faces on peds; few fine and very fine black concretions; slight effervescence with hydrogen peroxide; strongly acid (pH 5.2); clear wavy boundary. (5 to 18 inches thick)
B2--29 to 47 inches; dark reddish brown (2.5YR 2/4) silty clay, dark reddish brown (2.5YR 3/4) dry; moderate very fine and fine subangular blocky structure; slightly hard, firm, sticky and plastic; common fine tubular pores; weak patchy pressure faces on peds; few black concretions; slight effervescence with hydrogen peroxide in soil matrix; strong effervescence on the black concretions; slightly acid (pH 6.5); clear wavy boundary. (8 to 36 inches thick)
B3--47 to 74 inches; dark reddish brown (2.5YR 3/4) silty clay loam, dark red (2.5YR 3/6) dry; moderate medium blocky structure parting to moderate fine subangular blocky; hard, firm, sticky and plastic; few very fine tubular pores that contain black stains; strong continuous pressure faces on peds; few worm casts; few hard rock fragments; slight effervescence with hydrogen peroxide in soil matrix; few fine black concretions that effervesce with hydrogen peroxide; medium acid (pH 5.8).
TYPE LOCATION: Honolulu County, Hawaii; about 1/2 mile south of CPC loading lot on Highway 75, then l/2 miles west on Plantation road; site 450 feet north of plantation road; 21 degrees 28' 42" north latitude and 158 degrees 03' 43" west longitude.
RANGE IN CHARACTERISTICS: Gravelly alluvium underlies the soil below depths of four feet in some pedons, particularly near the drainageways where the alluvial fans have been dissected. Mean annual soil temperature is about 72 degrees F. The soil is dry in some horizon for more than 90 cumulative days in most years.
The Ap horizon has hue of 5YR or 2.5YR, and value of 3 or 4 dry.
The B horizon has chroma of 3 through 6. The B3 horizon is silty clay or silty clay loam.
COMPETING SERIES: These are the Haliimaile, Hoolehua, Kolekole, Lahaina, Pohakupu and Wahiawa series. Haliimaile soils have mean annual temperature less than 71.6 degrees F. Hoolehua soils have 5YR or yellower hue throughout. Kolekole and Pohakupu soils have oxidic mineralogy. Lahaina soils have patchy pressure faces on peds in the B3 horizon. Wahiawa soils have thin patchy clay films and slickensides in the lower part of the B2 horizon.
GEOGRAPHIC SETTING: Kunia soils are on terraces and fans. Slope is 0 to 15 percent. Elevations range from 700 to 1,000 feet. The soils formed in alluvium from material weathered from the basalts. Average annual rainfall is 30 to 40 inches. Mean annual temperature is about 71 degrees F., average January temperature is 68 degrees F., and average July temperature is 74 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Kolekole soils and the competing Lahaina and Wahiawa soils. Kolekole soils have a thin panlike layer at a depth of 15 to 50 inches.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate permeability.
USE AND VEGETATION: Mainly in pineapple and irrigated sugarcane. Very little of the soil remains in natural vegetation.
DISTRIBUTION AND EXTENT: On terraces and fans below the Waianae Range on the Island of Oahu, Hawaii. Kunia soils are of small extent, comprising about 6,300 acres.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Honolulu County, Hawaii. Soil Survey, Territory of Hawaii, 1949.
OSED scanned by SSQA. Last revised by state on 5/78.