LOCATION HANAMAULU HIEstablished Series
TAXONOMIC CLASS: Very-fine, ferruginous, isohyperthermic Humic Kandiudox
TYPICAL PEDON: Hanamaulu silty clay - sugarcane. (Colors are for moist soil unless otherwise noted. All textures are "apparent field textures.")
Ap1--0 to 5 inches; very dark grayish brown (10YR 3/2) silty clay, very dark grayish brown (2.5Y 3/2) dry; moderate medium and fine granular structure; hard, firm, sticky and plastic; many roots; slight effervescence with hydrogen peroxide; some material from Bto1 horizon mixed by plowing; extremely acid (pH 4.2); abrupt smooth boundary. (5 to 7 inches thick)
Ap2--5 to 11 inches; dark brown (7.5YR 3/4) silty clay, brown (7.5YR 4/3) dry; weak fine and very fine subangular blocky structure; hard, firm, sticky and plastic; common fine and very fine roots; many fine and very fine pores; slight effervescence with hydrogen peroxide; some material from horizon below mixed by plowing; very strongly acid (pH 4.8); clear smooth boundary. (6 to 7 inches thick)
Bto1--11 to 20 inches; dark reddish brown (5YR 3/3) silty clay, dark reddish brown (5YR 3/4) dry; strong very fine subangular blocky structure; hard, firm, sticky and plastic; common fine and very fine roots; common fine and many very fine pores; many moderately thick coatings on peds and in pores; coatings look like clay films; strongly acid (pH 5.1); gradual smooth boundary. (7 to 10 inches thick)
Bto2--20 to 36 inches; dark reddish brown (5YR 3/4) silty clay, same color dry; strong very fine subangular blocky structure; very hard, firm, sticky and plastic; common fine and few very fine roots; few fine and many very fine pores; continuous moderately thick coatings on peds and in pores; coatings look like clay films; very strongly acid (pH 5.0); gradual smooth boundary. (12 to 21 inches thick)
Bto3--36 to 54 inches; dark brown (7.5YR 3/4) silty clay loam, same color dry; strong very fine subangular blocky structure; very hard, firm, slightly sticky and slightly plastic; few fine and very fine roots; few fine and many very fine pores; continuous moderately thick coatings on peds and in pores; coatings look like clay films; pore coatings are strong brown (7.5YR 4/6); very strongly acid (pH 4.9); gradual smooth boundary. (12 to 22 inches thick)
Bto4--54 to 61 inches; dark brown (7.5YR 3/4) silty clay loam, same color dry; moderate very fine subangular blocky structure; very hard, firm, slightly sticky and slightly plastic; few fine and very fine roots; few fine and many very fine pores; continuous moderately thick coatings on peds and in pores; coatings look like clay films; pore coatings are strong brown (7.5YR 4/6); very strongly acid (pH 4.9); gradual smooth boundary. (7 to 21 inches thick)
Bto5--61 to 72 inches; dark brown (7.5YR 3/4) clay loam, 1/10 inch bands and pockets of yellowish red (5YR 3/6) and coatings and segregations of strong brown (7.5YR 5/6); weak fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few fine and very fine roots; few fine and very fine pores; few thin coatings that look like clay films; under 10 power hand lens the soil material has a sugary appearance; strongly acid (pH 5.1).
TYPE LOCATION: Island of Kauai, Kauai County, Hawaii; Kapaa Quadrangle; lat. 22 degrees 2 minutes 5 seconds N. and long. 159 degrees 23 minutes 59.3 seconds W. (Old Hawaiian Datum).
RANGE IN CHARACTERISTICS: The solum is about 3 feet to over 6 feet thick over gravel, stones and boulders. A few highly weathered pebbles and stones are throughout the solum in some pedons. The mean annual soil temperature is about 73 degrees F.
The A horizon has hue of 7.5YR through 2.5Y.
The B horizon has hue of 5YR or 7.5YR, value of 3 or 4, and chroma of 4 through 6.
COMPETING SERIES: (This needs updating.) These are the Lawai, Makapili, and Puhi series. Lawai soils have a silty clay B horizon and are moderately well drained. Makapili soils have a clay loam upper B horizon over a silty clay lower B horizon. Puhi soils lack an umbric epipedon.
GEOGRAPHIC SETTING: The Hanamaulu soils occur on stream terraces and steep terrace breaks and have slopes ranging from 3 to 40 percent. Elevation ranges from 200 to 700 feet. The soils formed in alluvium, usually of fine texture, underlain in some pedons by gravel, stones, and boulders. The mean annual rainfall is 60 to 100 inches. The mean annual temperature is about 73 degrees F., average January temperature is about 70 degrees F., and the average July temperature is about 74 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Kapaa and Hihimanu soils. Kapaa soils have gravel-size nodules containing more than 30 percent gibbsite within 40 inches of the surface. Hihimanu soils do not have an oxic horizon.
DRAINAGE AND PERMEABILITY: Moderately well drained; slow to rapid runoff, depending upon slope; moderately rapid permeability.
USE AND VEGETATION: Most areas are under cultivation. Sugarcane is the principal crop. Some areas are in brush and woodland. Principal vegetation in the uncultivated areas consists of associations of guava, pandanus, glenwoodgrass, ricegrass, hau, mango and associated plants.
DISTRIBUTION AND EXTENT: Island of Kauai, Hawaii. This series is of small extent, comprising 7,800 acres.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Island of Kauai, Kauai County, Hawaii, 1971.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - from the surface to 11 inches. (Ap horizons).
Oxic horizon - from 11 to 72 inches (Bto horizons).
FCC Classification: Cheik.
Edit Log: 12/03 SN. Horizon designations updated;
8/00 SN. Classification changed from Clayey, oxidic, isohyperthermic Tropeptic Umbriorthox due to changes in Taxonomy.
ADDITIONAL DATA: