LOCATION AKELELU HI
Established Series
KH-RTG
05/2012
AKELELU SERIES
The Akelelu series consists of moderately deep, well drained soils that formed in basic volcanic ash deposited over basic pahoehoe lava. Slopes range from 2 to 10 percent. The mean annual rainfall is about 1,295 millimeters (51 inches), and the mean annual temperature is about 13 degrees C. (55 degrees F.)
TAXONOMIC CLASS: Medial, amorphic, isomesic Eutric Pachic Fulvudands
TYPICAL PEDON: Akelelu medial silt loam, 4 percent slope under koa trees and a grass understory at an elevation of 1,460 meters (4,800 feet). (Colors are for moist soil unless otherwise noted. When described on 6/30/98 the soil was dry throughout. The soil temperature was 15 degrees C. (59 degrees F.) at a depth of 50 centimeters (20 inches). All textures are "apparent field textures". pH was measured using organic dyes.)
A1--0 to 10 centimeters (0 to 4 inches); black (10YR 2/1) medial silt loam, very dark brown (10YR 2/2) dry; strong fine and medium granular structure; slightly hard, friable, weakly smeary, slightly sticky and slightly plastic; many very fine and fine roots; many very fine and fine interstitial pores; strongly acid (pH 5.4); abrupt wavy boundary.
A2--10 to 18 centimeters (4 to 7 inches); black (10YR 2/1) medial silt loam, very dark brown (10YR 2/2) dry; weak medium subangular blocky structure parting to moderate fine and medium granular; slightly hard, friable, weakly smeary, slightly sticky and slightly plastic; many very fine and fine roots; many very fine and fine interstitial pores; moderately acid (pH 5.6); abrupt wavy boundary. (Combined thickness of the A horizons ranges from 5 to 25 centimeters (2 to 10 inches))
Bw1 --18 to 38 centimeters (7 to 15 inches); dark brown (7.5YR 3/2) medial loam, dark brown (10YR 3/3) dry; weak medium subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky and nonplastic; many very fine, fine and medium and few coarse roots; many very fine and fine interstitial pores; slightly acid (pH 6.2); abrupt wavy boundary. (10 to 25 centimeters (4 to 10 inches) thick)
2Bw2--38 to 46 centimeters (15 to 18 inches); dark reddish brown (5YR 3/4) medial loam, yellowish red (5YR 4/6) dry; weak medium subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky and nonplastic; many very fine, fine and medium and few coarse roots; many very fine and fine interstitial pores; 5 percent subrounded gravel; moderately acid (pH 6.0); abrupt broken boundary.
2Bw3--46 to 53 centimeters (18 to 21 inches); very dark brown (7.5YR 2.5/2) medial fine sandy loam, dark brown (7.5YR 3/4) dry; massive; soft, very friable, nonsticky and nonplastic; many very fine, fine and medium and few coarse roots; many very fine and fine interstitial pores; 5 percent subrounded gravel; slightly acid (pH 6.2); clear wavy boundary.
2Bw4--53 to 69 centimeters (21 to 27) inches; dark reddish brown (5YR 2.5/2) medial fine sandy loam, dark brown (7.5YR 3/3) dry; massive; soft, very friable, nonsticky and nonplastic; many very fine, fine, and medium and few coarse roots; many very fine and fine interstitial pores; slightly acid (pH 6.2); clear wavy boundary. (Combined thickness of 2Bw horizons 13 to 40 centimeters (5 to 15 inches))
3Bw5--69 to 76 centimeters (27 to 30 inches); very dark brown (7.5YR 2.5/2) medial loam, dark yellowish brown (10YR 4/4) dry; massive; soft, very friable, nonsticky and nonplastic; common very fine, fine and medium roots; many very fine and fine interstitial pores; slightly acid (pH 6.2); clear wavy boundary.
3Bw6--76 to 86 centimeters (30 to 34 inches); very dark brown (7.5YR 2.5/3) medial loam, dark yellowish brown (10YR 4/6) dry; massive; soft, very friable, nonsticky and nonplastic; common very fine, fine and medium roots; many very fine and fine interstitial pores; 5 percent angular pahoehoe gravel; slightly acid (pH 6.2); abrupt wavy boundary. (Combined thickness of 3Bw horizons 13 to 40 centimeters (5 to 15 inches).)
4R--86 to 97 centimeters (34 to 28 inches); hard pahoehoe lava.
TYPE LOCATION: Hawaii Volcanoes National Park; from intersection of State Hwy 11 and Mauna Loa Strip Road travel 5.6 miles north on Mauna Loa Strip Road and park on north (right) side of road; walk at a heading of 30 degrees magnetic for 15 meters (50 feet) to type location; Kilauea Crater Quadrangle; lat. 19 degrees 27 minutes 38.65 seconds N. and long. 155 degrees 20 minutes 28.95 seconds W. (Old Hawaiian Datum measured by GPS/PLGR ( 350 feet).)
RANGE IN CHARACTERISTICS:
Depth to bedrock: 50 to 100 centimeters (20 to 40 inches).
Mean annual soil temperature: 12 to 15 degrees C. (54 to 59 degrees F.).
Rock fragments: Less than 15 percent throughout the profile.
Soil reaction: Strongly acid to slightly acid.
A horizon
Texture: Medial loam or medial silt loam.
Structure: Granular or subangular blocky.
Smeariness: Nonsmeary or weakly smeary.
B horizon
Hue: 5YR to 10YR.
Value: 2 to 3 moist.
Chroma: 1 to 4 moist.
Texture: Medial fine sandy loam, medial loam, or medial silt loam.
Structure: Subangular blocky or massive.
Coarse fragments: Less than 15 percent in some horizons.
COMPETING SERIES: There are no competing series. Ha`a,
Ki, and Pu`iwa soils are similar. Ha`a soils have 3A horizons and are 102 to 152 centimeters (40 to 60 inches) deep. Ki soils have lapili and are sandy in the upper part of the profile and are more than 152 centimeters (60 inches) deep. Pu`iwa soils do not have massive 3Bw horizons.
GEOGRAPHIC SETTING: Akelelu soils are on Mauna Loa pahoehoe flows 3,000 to 5,000 years old at elevations of 1,340 to 1,700 meters (4,400 to 5,600 feet). Slopes range from 2 to 10 percent. The mean annual rainfall is 1,270 to 1,525 millimeters (50 to 60 inches), with about 75 percent of the rainfall occurring between October and April. The mean annual pan evaporation is 1,270 to 1,525 millimeters (50 to 60 inches). The mean annual air temperature is 12 to 15 degrees C. (54 to 59 degrees F.).
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ke`amoku,
Kulalio, Mauna`iu, and the similar Ha`a soils. Ke`amoku and Kulalio soils are skeletal in the lower part of the control section. Mauna`iu soils are lithic, less than 50 centimeters (20 inches) to bedrock.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is very low to low. Permeability is rapid in the soil and very slow in the underlying pahoehoe bedrock.
USE AND VEGETATION: These soils are used for National Park Service land and pasture. Vegetation is aalii (Dodonaea viscosa), bracken fern (Pteridium aquilinum), koa (Acacia koa), pukiawe (Styphelia tameiameiae), and various grasses.
DISTRIBUTION AND EXTENT: These soils occur within Hawaii Volcanoes National Park and neighboring ranches; MLRA 160. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Island of Hawaii, Hawaii County, Hawaii, 2012. The name is coined.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Andic soil properties - from 0 to 86 centimeters (0 to 34 inches).
Lithic contact - at 86 centimeters (34 inches).
Soil temperature - mean summer and mean winter soil temperatures differ by less than 6 degrees C. (iso temperature regime)
Soil moisture - not dry in some or all parts for 90 days or more (Udic moisture regime).
Edit Log: 2/01 KH. Changed runoff from high to medium.
8/02 KH. Changed horizon designations and added "medial" modifier to textures.
ADDITIONAL DATA: Similar Kulalio soil NSSL S97HI-001-009.
National Cooperative Soil Survey
U.S.A.