LOCATION HOOLEHUA HIEstablished Series
TAXONOMIC CLASS: Fine, parasesquic, isohyperthermic Oxic Haplustepts
TYPICAL PEDON: Hoolehua silty clay - cultivated. (Colors are for moist soil unless otherwise noted. All textures are "apparent field textures.")
Ap1--0 to 9 inches; dark reddish brown (5YR 3/3) silty clay, dark reddish gray (5YR 4/2) dry; cloddy due to tillage; hard, irm, sticky and plastic; compacted by agriculture machinery; common roots; few medium and coarse tubular pores; violent effervescence with hydrogen peroxide; extremely acid (pH 3.9); clear smooth boundary. (8 to 9 inches thick)
Ap2--9 to 15 inches; dark reddish brown (5YR 3/3) moist and dry
silty clay; cloddy; hard, friable, sticky and plastic; few roots; few very fine tubular pores; violent effervescence with hydrogen peroxide; extremely acid (pH 4.4); clear wavy boundary. (4 to 7 inches thick)
B11--15 to 21 inches; dark reddish brown (5YR 3/3) moist and dry silty clay loam; weak fine and medium subangular blocky structure; slightly hard, very friable, sticky and plastic; few roots; many vry fine and fine pores, common medium tubular pores; many very fine black concretions; violent effervescence with hydrogen peroxide; in the upper part thin patchy black coats (2 mm x 5 mm x 1/4 mm) that are coated with reddish brown material do not effervesce with hydrogen peroxide; medium acid (pH 6.0); clear wavy boundary. (5 to 9 inches thick)
B12--21 to 27 inches; dark reddish brown (5YR 3/3) moist and dry silty clay; weak fine and medium subangular blocky structure slightly stronger than B12 horizon; hard, friable, sticky and plastic; many very fine and fine pores, common medium tubular pores; common black stains in pores; many very fine black concretions; violent effervescencewith hydrogen peroxide; slightly acid (pH 6.3); clear wavy boundary. (6 to 7 inches thick)
B21--27 to 49 inches; dark reddish brown (5YR 3/3,3/4) moist and
dry silty clay; strong vey fine subangular blocky structure, few pockets of weak and medium very fine subangular blocky structure; very hard, firm, sticky and plastic; compact in place; common very fine tubular pores; common black stains on faces of peds; almost continuous coatings on peds; many very fine black concretions; common hard earthy lumps break down after prolonged rubbing; strong effervescence with hydrogen peroxide; slightly acid (pH 6.4); gradual wavy boundary. (19 to 26 inches thick)
B22--49 to 64 inches; dark reddish brown (5YR 3/4) moist and dry silty clay; moderate and strong fine subangular blocky structure; very hard, firm, sticky and plastic; slightly firm in place; common very fine tubular pores; few black stains on faces of peds; common thin films on faces of peds; common very fine black concretions; many hard earth lumps break down after prolonged rubbing; moderate effervescence with hydrogen peroxide; slightly acid (pH 6.2).
TYPE LOCATION: Island of Molokai, Maui County, Hawaii; Kaupakakai Quadrangle 21 degrees 9 feet 34 inches N. latitude and 157 degrees 3 feet 8 inches W. longitude; approximately 3/4 mile west of Kualapuu Post Office.
RANGE IN CHARACTERISTICS: Stratification of the soil ranges from moderate to none. Few to many pebbles and cobbles are at varying depths in some pedons. Th mean annual soil temperature is about 72 degrees F. Mica is throughout the soil. The soil is dry in some horizon below 10 inches for more than 90 cumulative days in most years. Hue of the soil is 5YR pr 7.5YR, and chroma ranges from 2 through 4.
COMPETING SERIES: These are the Honouliuli, Kunia, Lahaina, Waialua, Waihuna, Waikapu, and Waipahu series. Honouliuli soils are clay and are very sticky and very plastic. Kunia soils have 2.5YR or redder hue in the B horizon. Lahaina soils have 2.5YR or redder hue in the B horizon and lack black stains in the B horizon. Waihuna soils have mean annual soil temperature of less than 71.6 degrees F., clay texture, and they are very sticky and very plastic throughout. Waikapu soils are silty clay loam in the B horizon and have slickensides in the lower part of the B horizon. Waipahu soils have hue of 7.5YR or yellower and prismatic structure and slickensides in the B horizon.
GEOGRAPHIC SETTING: Hoolehua soils are in basins and on alluvial fans and have slopes of 0 to 35 percent. Elevation ranges from 400 to 1,300 feet. The soils formed in alluvium material weathered from basic igneous rock. The mean annual precipitation is from 20 to 35 inches. The mean annual temperature is about 72 degrees F.; the average January temperature is about 69 degrees F.; and the average July temperature is about 76 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Kalae and Molokai soils and the competing Lahaina and Waikapu soils. Kalae soils have an argillic horizon that has continuous clay films. Molokai soils have 2.5YR or redder hue in the B horizon, and weak prismatic structure in the upper part.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: Used mainly for growing pineapple and pasture. Natural vegetation is lantana, guineagrass, and ilima.
DISTRIBUTION AND EXTENT: These soils are on the islands of Molokai and Lanai. The extent is about 8,000 acres.
MLRA OFFICE RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Island of Molokai, Maui County, Hawaii, 1949.