LOCATION WAIKAPU HIEstablished Series
TAXONOMIC CLASS: Fine, parasesquic, isohyperthermic Torroxic Haplustolls
TYPICAL PEDON: Waikapu silty clay loam - cultivated. (Colors are for moist soil unless otherwise noted. All textures are "apparent field textures.")
Ap1--0 to 4 inches; dark reddish brown (5YR 2/3) silty clay loam, dark reddish brown (5YR 3/3) dry; weak very fine granular structure; soft, very friable, sticky and plastic; few roots; many interstitial pores; common very fine vertical tubular pores; many fine black concretions; violent effervescence with hydrogen peroxide; strongly acid (pH 5.1); clear wavy boundary. (3 to 5 inches thick)
Ap2--4 to 12 inches; dark reddish brown (5YR 2/3) light silty clay loam, reddish brown (5YR 4/4) dry; weak medium and fine subangular blocky structure, some pockets of weak very fine granular structure; soft, friable, sticky and plastic; many roots; many very fine and few fine tubular pores; common fine black concretions; violent effervescence with hydrogen peroxide; slightly acid (pH 6.1); gradual wavy boundary. (7 to 10 inches thick)
B1--12 to 24 inches; dark reddish brown (2.5YR 3/4) silty clay loam, reddish brown (2.5YR 4/4) dry; strong fine and very fine angular and subangular blocky structure; slightly hard, friable, sticky and plastic; firm in place; few roots; many very fine and fine and few medium tubular pores; patchy glaze on faces of peds; common fine black concretions; violent effervescence with hydrogen peroxide; common fine hard earthy lumps which break down slowly upon rubbing; neutral (pH 7.0); gradual wavy boundary. (10 to 14 inches thick)
B21--24 to 34 inches; dark reddish brown (2.5YR 3/4) moist and dry silty clay loam; moderate medium subangular blocky structure parting to strong fine and very fine angular blocky; soft, friable, sticky and plastic; moderately firm in place; many very fine and fine and few medium tubular pores; weakly expressed patchy pressure faces; many black concretions, commonly up to 2 mm. in diameter; violent effervescence with hydrogen peroxide; neutral (pH 7.2); gradual wavy boundary. (8 to 12 inches thick)
B22--34 to 44 inches; dark reddish brown (5YR 5/3) silty clay loam, dark reddish brown (5YR 3/4) dry; weak medium and fine subangular blocky structure; few weakly grooved slickensides; soft, very friable sticky and plastic; many very fine and fine and common medium tubular pores; many black concretions; violent effervescence with hydrogen peroxide; neutral (pH 7.2); clear wavy boundary. (8 to 12 inches thick)
B3--44 to 60 inches; dark red (2.5YR 2/6) silty clay loam, dark reddish brown (2.5YR 3/4) dry; weak medium subangular blocky structure parting to moderate fine and very fine subangular blocky; few slickensides; soft, friable, sticky and plastic; many very fine and fine and common medium tubular pores; patchy glaze on some peds; common fine hard earthy lumps that are broken down by persistent rubbing; few fine black concretions; slight effervescence with hydrogen peroxide; neutral (pH 7.2).
TYPE LOCATION: Island of Lanai, Maui County, Hawaii; Dole Company plantation, 100 feet north of the south end of Block C-8 in field 5514.
RANGE IN CHARACTERISTICS: Black concretions are throughout the solum and range in size from fine specks to 3 millimeters. Effervescence with hydrogen peroxide is strong to violent in the A and B2 horizons. Mean annual soil temperature is about 73 degrees F. The soil is dry below a depth of 10 inches for more than 6 months in most years. The solum has hue of 5YR or 2.5YR.
The A horizon has value and chroma of 2 or 3 moist and value of 3 or 4 dry.
The B horizon has value of 2 or 3 moist, 3 or 4 dry, and chroma of 3 through 6 moist. Slickensides are few to common in the lower part of the B horizon.
COMPETING SERIES: These are the Ewa, Keahua, Wahikuli, and Waiakoa series. Ewa, Keahua and Waiakoa soils lack slickensides. Waiakoa and Wahikuli soils are 20 to 40 inches deep over bedrock.
GEOGRAPHIC SETTING: The Waikapu soils are on gently to moderately sloping alluvial fans at elevations of 100 to 1,250 feet. The soils formed in old alluvium from material washed from basic igneous rocks. Average annual rainfall is 15 to 25 inches. Average January temperature is about 71 degrees F., average July temperature is about 77 degrees F., and the mean annual temperature is about 73 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Holomua Molokai and Uwala soils. Holomua soils lack pressure faces and slickensides. Molokai soils have prismatic structure in the B horizon and lack slickensides. Uwala soils are medium acid in the B horizon.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: Used for growing pineapple, pasture and wildlife. Wild vegetation is lantana (Lantana camara), bermudagrass (Cynodon dactylon), illima (Sida fallax), and feather fingergrass (Chloris virgata).
DISTRIBUTION AND EXTENT: This soil is on the islands of Molokai and Lanai, Hawaii. The series is inextensive, with a total of about 3,500 acres.
MLRA OFFICE RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Island of Maui, Maui County, Hawaii, 1949.
OSED scanned by SSQA. Last revised by state on 3/78.