LOCATION PUUIKI HITentative Series
TAXONOMIC CLASS: Euic, isomesic, micro Lithic Ustifolists
TYPICAL PEDON: Puuiki very cobbly highly decomposed plant material, on a north facing, slightly convex, 10 percent slope in abandoned pasture at an elevation of 1340 meters (4395 feet). (Colors are for moist soils unless otherwise noted. All textures are "apparent field textures". pH measured with electrode in 1:1 water. When described on February 25, 1997, the soil was dry throughout.)
Oa/2C--0 to 13 centimeters (0 to 5 inches); black (10YR 2/1) very cobbly highly decomposed plant material , very dark brown (10YR 2/2) dry; moderate very fine and fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine, and common medium roots; many very fine and fine interstitial pores; 50 percent subangular cobbles; slightly acid (pH 6.1); abrupt wavy boundary. (5 to 25 centimeters {2 to 10 0inches} thick)
2R--13 centimeters (5 inches); hard, massive pahoehoe lava; class 2 (10-45 cm) joint fractures.
TYPE LOCATION: Island of Hawaii, Hawaii County, Hawaii; from Pu`u Wa`awa`a Ranch, drive west 0.6 miles on 4WD road, turn south at fence line and drive past Potato Hill to Shangri-La; pedon is located about 305 meters (1000 feet) west of 4WD road. Hualalai Quadrangle; lat. 19 degrees 44 minutes 9.9 seconds N. and long. 155 degrees 51 minutes 2.6 seconds W. (GPS/PLGR; Old Hawaiian Datum).
RANGE IN CHARACTERISTICS:
Depth to bedrock: 5 to 25 centimeters (2 to 10 inches).
Mean annual soil temperature: 11 to 15 degrees C. (52 to 59 degrees F.)
Rock fragments: 15 to 60 percent by volume and range in size from gravel to cobble size lava rocks.
Organic carbon (by weight): 25 to 30 percent of the less than 2.0 mm soil material.
Oa/2C horizon
Hue: Neutral or 10YR.
Value: 2 moist or 2 or 3 dry.
Chroma: 0, 1, or 2 moist or dry.
Texture: Very cobbly highly decomposed plant material or cobbly highly decomposed plant material.
Soil reaction: Moderately acid to slightly acid (pH 5.6 to 6.5).
COMPETING SERIES: This is the Kekake series. Kekake soils are moist in the control section from April through October.
GEOGRAPHIC SETTING: Puuiki soils are on upper elevation, leeward slopes of Hualalai volcano at elevations from 1067 to 1829 meters (3500 to 6000 feet). These soils are in depressions of constructional landscapes consisting of nearly level to steep pahoehoe flows that are less than 5,000 years old. Slope gradients range from 2 to 40 percent. The soils formed in organic material consisting of decomposed leaves, twigs, wood; and to a lesser extent basic volcanic ash, cinders, and weathered lava. The mean annual rainfall ranges from 760 to 1020 millimeters (30 to 40 inches), with most of the rainfall occurring from January through July. The mean annual pan evaporation ranges from 1270 to 1520 millimeters (50 to 60 degrees). 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, Kamawai, and Nawahine series. Halekula and Kamawai soils are mineral soils over `a`a lava. Nawahine soils are mineral soils underlain with cinders.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is negligible in depressions on gentle slopes and high to very high on steeper slopes. Permeability is rapid in the soil and very slow in the underlying bedrock.
USE AND VEGETATION: Used for grazing and wildlife habitat. The natural vegetation is kikuyugrass (Pennisetum clandestinum), ohia lehua (Metrosideros polymorpha), and koa (Acacia koa).
DISTRIBUTION AND EXTENT: North Kona District, Island of Hawaii; MLRA 161A nd 161B. The soils are 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 from July through January in most years (Ustic moisture regime).
Diagnostic horizons and features recognized in this pedon are:
Sapric soil materials - from a depth of 0 to 13 centimeters (0 to 5 inches) (Oa/2C horizon).
Lithic contact - at a depth of 13 centimeters (5 inches) (2R horizon).
ADDITIONAL DATA: Puuiki NSSL sample S97HI-001-005 (reference sample) and S97HI-001-007 (type location).