LOCATION KAMAWAI HI

Tentative Series
MRK-RTG
05/2012

KAMAWAI SERIES

The Kamawai series consists of shallow, well drained soils that formed in basic volcanic ash in `a`a lava. Slopes range from 2 to 50 percent. The mean annual rainfall is about 890 millimeters (35 inches) and the mean annual temperature is about 12 degrees C (54 degrees F).

TAXONOMIC CLASS: Medial-skeletal, amorphic, isomesic Lithic Haplustands

TYPICAL PEDON: Kamawai extremely cobbly highly organic medial silt loam, on a north facing, slightly convex, 12 percent slope under forest at an elevation of 1335 meters (4380 feet). (Colors are for moist soil unless otherwise noted. All textures are "apparent field textures." pH measured with electrode in 1:1 water. When described on August 8, 1996, the soil was moist throughout.) The 2C part of these horizons consist of unconsolidated `a`a lava fragments of variable size.

2C1/A1--0 to 28 centimeters (0 to 11 inches); black (10YR 2/1) extremely cobbly highly organic medial silt loam , very dark brown (10YR 2/2) dry; strong very fine and fine granular structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and fine, and few medium roots; many very fine and fine interstitial pores and few very fine vesicular pores; 40 percent angular `a`a cobbles and 40 percent angular `a`a gravel; slightly acid (pH 6.1); clear wavy boundary. (25 to 31 centimeters {10 to 12 inches} thick)

2C2/A2--28 to 50 centimeters (11 to 20 inches); black (10YR 2/1) extremely cobbly highly organic medial silt loam , very dark brown (10YR 2/2) dry; strong fine and medium granular structure; slightly hard, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores and few very fine vesicular pores; 50 percent angular `a`a gravel and 30 percent angular `a`a cobbles; slightly acid (pH 6.1); abrupt wavy boundary. (20 to 25 centimeters {8 to 10 inches} thick)

2R--50 centimeters (20 inches); hard, massive `a`a blue rock; class 2 (10-45 centimeters) joint fractures.

TYPE LOCATION: Island of Hawaii, Hawaii County, Hawaii; from Puu Waawaa Ranch, drive west 0.6 miles on 4WD road, turn south at fence line and drive 2.9 miles on 4WD road to Shangri-la; pedon is located about 152 meters (500 feet) south of 4WD road junction and 457 meters (1500 feet) east of Shangri-la. Hualalai Quadrangle; lat. 19 degrees 44 minutes 5.6 seconds N. and long. 155 degrees 50 minutes 42.9 seconds W. (GPS/PLGR); Old Hawaiian Datum.

RANGE IN CHARACTERISTICS:
Depth to bedrock: 25 to 50 centimeters (10 to 20 inches).
Mean annual soil temperature: 11 to 15 degrees C (52 to 59 degrees F).
Rock fragments: 60 to 85 percent by volume of the pedon and range in size from gravel to boulders, but are primarily gravel and cobble size lava rocks.
Organic carbon (by weight): 20 to 25 percent of the less than 2.0 mm soil material.

2C/A horizon
Hue: Neutral or 10YR.
Value: 2 moist and 2 or 3 dry.
Chroma: 0, 1, or 2 moist or dry.
Soil reaction: Strongly acid to slightly acid (pH 5.1 to 6.5).

COMPETING SERIES: These are the Lapa and Puukala series. Lapa soils formed in volcanic ash and glacial till over basalt. Puukala soils are shallow over pahoehoe lava and are moist in the control section from April to October.

GEOGRAPHIC SETTING: Kamawai soils are on north and northwest slopes on the undissected upland of Hualalai Volcano at elevations from 1067 to 1829 meters (3500 to 6000 feet). These soils are on all hillslope positions of constructional landscapes consisting of undulating to very steep `a`a lava flows that are 1,500 to 3,000 years old. Slope gradients range from 2 to 50 percent. The soils formed in basic volcanic ash over `a`a lava. The mean annual rainfall ranges from 762 to 1016 millimeters (30 to 40 inches), with most of the rainfall occurring from January through July. The mean annual pan evaporation ranges from 1270 to 1524 millimeters (50 to 60 inches). The mean annual temperature ranges from 10 to 14 degrees C (50 to 57 degrees F). The mean summer soil temperature and the mean winter soil temperature differ by less than 6 degrees C (11 degrees F).

GEOGRAPHICALLY ASSOCIATED SOILS: These are Halekula, Nawahine, and Puuiki series. Halekula soils have a lithic contact at 50 to 102 centimeters (20 to 40 inches). Nawahine soils are medial over cindery. Puuiki soils have greater than 25 percent organic carbon (by weight) in the less than 2.0 mm soil material and are over pahoehoe lava.

DRAINAGE AND PERMEABILITY: Well drained. Runoff is negligible in depressions on gentle slopes and high to very high on steeper slopes. Permeability is very rapid in the soil and very slow in the underlying bedrock.

USE AND VEGETATION: Used for grazing and wildlife habitat. The natural vegetation is ohia lehua (Metrosideros polymorpha) and kikuyugrass (Pennisetum clandestinum).

DISTRIBUTION AND EXTENT: North Kona District, Island of Hawaii; MLRA 161B. The series is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.

SERIES PROPOSED: Island of Hawaii, Hawaii County, Hawaii, 1996.

REMARKS: Soil moisture - usually moist, but dry in some or all parts for short intermittent periods totaling 90 or more days during the months of July through January in most years (Ustic moisture regime).
Diagnostic horizons and features recognized in this pedon include:
Mollic epipedon - from a depth of 0 to 50 centimeters (0 to 20 inches) (2C/Oa horizons).
Andic soil properties - from a depth of 0 to 50 centimeters (0 to 20 inches) (2C/Oa horizons).
Lithic contact - at a depth of 50 centimeters (20 inches) (2R horizon).

ADDITIONAL DATA: NASIS User Pedon ID 01HI601009. NSSL sample S97HI-001-006.

National Cooperative Soil Survey
U.S.A.