LOCATION MOLOKAI HIEstablished Series
TAXONOMIC CLASS: Very-fine, kaolinitic, isohyperthermic Typic Eutrotorrox
TYPICAL PEDON: Molokai silty clay loam - pineapple. (Colors are for moist soil unless otherwise noted. All textures are "apparent field textures.")
Ap1--0 to 7 inches; dark reddish brown (2.5YR 3/4) silty clay loam, dark red (2.5YR 3/6) dry; weak very fine, fine and medium granular structure; slightly hard, friable, slightly sticky and plastic; many roots; many interstitial pores; many very fine black concretions that effervesce with hydrogen peroxide; strong effervescence with hydrogen peroxide; extremely acid (pH 4.4); clear wavy boundary. (6 to 7 inches thick)
Ap2--7 to 15 inches; dark reddish brown (2.5YR 3/4) silty clay loam, dark red (2.5R 3/6) dry; weak medium and coarse subangular blocky structure parting to moderate fine and very fine granular; slightly hard, friable, sticky and plastic; common roots; common very fine tubular and interstitial pores; common fine black concretions; violent effervescence with hydrogen peroxide; very strongly acid (pH 4.6); clear smooth boundary. (8 to 9 inches thick)
Bo1--15 to 35 inches; dark reddish brown (2.5YR 3/4) silty clay loam, red (2.5YR 4/6) dry; weak coarse prismatic structure parting to weak coarse subangular blocky; slightly hard, friable, sticky and plastic; many very fine and fine tubular pores; few shiny patchy faces on prisms; common fine black concretions; strong effervescence with hydrogen peroxide; slightly acid (pH 6.5); gradual wavy boundary. (14 to 22 inches thick)
Bo2--35 to 64 inches; dark reddish brown (2.5YR 3/4) silty clay loam, red (2.5YR 4/6) dry; weak coarse prismatic structure parting to strong very fine and fine subangular blocky; moderately compact in place, slightly hard, firm, sticky and plastic; many very fine and common fine tubular pores; common patchy pressure faces on peds; common patchy clay films on faces of peds; few very fine black concretions; moderate effervescence with hydrogen peroxide; neutral (pH 6.6); gradual wavy boundary. (27 to 30 inches thick)
Bo3--64 to 72 inches; dark reddish brown (5YR 3/3) clay loam, dark reddish brown (5YR 3/4) dry; moderate fine and very fine subangular blocky and angular blocky structure; slightly hard, friable, slightly sticky and plastic; common very fine and fine tubular pores; thin patchy clay films on peds; red (2.5YR 4/6) clay films lining larger pores; common hard earthy lumps; few very fine black concretions; slight effervescence with hydrogen peroxide; neutral (pH 6.6).
TYPE LOCATION: Island of Molokai, Maui County, Hawaii; Kaunakakai Quadrangle - 21 degrees 08 minutes 36 seconds north latitude and 157 degrees 03 minutes 05 seconds west longitude; about 4.7 miles west of Kaunakakai Post Office and 0.35 miles north of junction of Highways 46 and 47 and about 200 feet west of Highway 47.
RANGE IN CHARACTERISTICS: Depth to bedrock is over 60 inches. The number and size of black concretions that effervesce with hydrogen peroxide decrease as depth increases. Some weathered rock fragments are throughout the soil, but mostly below depths of 40 inches. Mean annual soil temperature is about 73 degrees F.
The A horizon has hue of 5YR, 2.5YR, or 10R, moist value of 2 or 3, moist chroma of 4 of 5, and dry chroma of 4 through 6.
The Bo horizons have hue of 2.5YR or 10R, moist value of 2 or 3 dry chroma of 4 through 6 and moist chroma of 3 or 4.
COMPETING SERIES: These are the Kahana, Lahaina, and Wahiawa series. Kahana soils have silty clay textures throughout the solum and do not have prismatic structure. Lahaina soils have silty clay texture in the upper part of the solum and do not have prismatic structure. Wahiawa soils have silty clay textures and black manganese stains throughout the solum and do not have prismatic structure.
GEOGRAPHIC SETTING: The Molokai soils are on uplands at elevations from near sea level to 1,500 feet. Slopes are 0 to 25 percent. The soils formed in residuum weathered from basic igneous rocks. Mean annual rainfall is 20 to 25 inches. The average January temperature is about 71 degrees F. average July temperature is about 77 degrees F., and mean annual temperature is about 73 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Holomua, Keahua and Uwala soils and the competing Lahaina soils. Holomua, Keahua and Uwala soils do not have an oxic horizon.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff, depending on slopes; moderate permeability.
USE AND VEGETATION: Used for the production of pineapple, pasture, irrigated sugarcane and for wildlife habitat. Vegetation is kiawe (Prosopis pallida), pitted beardgrass (Bothriochloa barbinodis perforatus), feather fingergrass (Chloris virgata), lantana (Lantana camara),ilima (Sida cordifolia), and buffelgrass (Cenchrus ciliaris).
DISTRIBUTION AND EXTENT: Islands of Molokai, Lanai, Maui, and Oahu, Hawaii. The series is moderately extensive comprising about 36,500 acres.
MLRA OFFICE RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Island of Molokai, Maui County, Hawaii, 1949.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
ochric epipedon- The zone from the surface to 15 inches (Ap1, Ap2)
oxic horizon- The zone from 15 to 72 inches (Bo1, Bo2, Bo3)