LOCATION PANAEWA HI

Established Series
Rev. HHS/RCH/PGN/AMS
06/2012

PANAEWA SERIES

The Panaewa series consists of shallow, moderately well drained soils that formed in material weathered from volcanic ash which overlies pahoehoe lava. Slopes range from 2 to 10 percent. Mean annual rainfall is about 3,900 millimeters (154 inches) and mean annual temperature is 23 degrees C (73 degrees F).

TAXONOMIC CLASS: Hydrous-skeletal, ferrihydritic, isohyperthermic Lithic Hydrudands

TYPICAL PEDON: Panaewa very cobbly hydrous loam on an east-facing, 1 percent slope in lowland forest at an elevation of 118 meters (390 feet). (Colors are for moist soils unless otherwise noted. All textures are "apparent field textures". pH measured using an Oakton microprocessor based pH meter. When described on March 1, 2005, the soil was moist from 0 to 40 cm (0 to 16 inches).)

Ap/2C--0 to 10 centimeters (0 to 4 inches); very dark brown (10YR 2/2) very cobbly hydrous loam, very dark grayish brown (10YR 3/2) dry; moderate very fine subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; common fine roots throughout; common very fine dentritic tubular pores throughout; moderately smeary; 25 percent subrounded cobbles and 10 percent subrounded gravel; moderately acid (pH 5.7); the 2C part of this horizon consists of unconsolidated pahoehoe lava fragments of variable size; clear smooth boundary. (10 to 20 centimeters {4 to 8 inches} thick)

2C2/Bw--10 to 40 centimeters (4 to 16 inches); very dark brown (10YR 2/2) extremely stony hydrous loam, dark brown (10YR 3/3) dry; weak very fine subangular blocky structure; soft, very friable, slightly sticky, plastic; few fine roots throughout; common very fine dentritic tubular pores throughout; moderately smeary; 50 percent subrounded stones and 15 percent subrounded cobbles; strongly acid (pH 5.5); abrupt smooth boundary. (10 to 30 centimeters {4 to 12 inches} thick)

2R-- 40 centimeters (16 inches); pahoehoe lava.

TYPE LOCATION: Island of Hawaii. From the village of Keaau, enter Shipman Park on the northwest side of Highway 11. Follow the road to the left and continue through the park to the Keaau Armory. From the armory, follow the ranch road northwest through the red pipe gate approximately 100 yards to the first road turning to the right. Proceed on this road for 0.5 miles to the type location at Hilo Quadrangle; 19 degrees, 37 minutes, 54.1 seconds North latitude and 155 degrees, 03 minutes, 06.0 seconds West longitude (Old Hawaiian Datum, +/- 12 ft; measured by Garmin GPS).

RANGE IN CHARACTERISTICS:
Soil moisture: The soil is typically moist throughout the profile. Precipitation exceeds evapotranspiration in all months of normal years (perudic soil moisture regime).
Soil temperature: 22 C (72 degrees F) or higher.
Depth to bedrock: 20 to 50 centimeters (8 to 20 inches).

A horizon
Hue: 7.5YR or 10YR.
Chroma: 1 or 2 moist.
Texture: Cobbly, very cobbly, or extremely cobbly hydrous loam.
Structure: Weak to moderate, very fine or fine, granular or subangular blocky.
Soil reaction: Strongly acid to moderately acid (pH 5.1 to 6.0).
Rock fragments: 15 to 80 percent by volume of the pedon and range in size from gravel to stone size pahoehoe lava rocks.

2C/Bw horizon
Hue: 7.5YR or 10YR.
Value: 2 to 3 moist.
Chroma: 2 or 3 moist.
Texture: Very cobbly, extremely cobbly, very stony, extremely stony with fines being hydrous loam, hydrous silt loam or hydrous sandy loam.
Structure: Weak or moderate subangular blocky.
Soil reaction: Strongly acid to slightly acid (pH 5.1 to 6.5).
Rock fragments: 35 to 89 percent by volume of the pedon and range in size from gravel to stone size pahoehoe lava rocks.

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: The Panaewa soils are at elevations ranging from 0 to 366 meters (0 to 1,200 feet) on the low undulating eastern windward mountain slopes of Mauna Loa and Kilauea volcanoes. These soils are in constructional landscapes consisting of nearly level pahoehoe flows that are 500 to 11,000 years old. Slope gradients range from 2 to 10 percent. The soils formed in volcanic ash over pahoehoe lava and have had extensive mechanical manipulation. Mean annual rainfall is 3,000 to 5,000 millimeters (118 to 197 inches) with most of the rainfall occurring from October through April. The mean annual pan evaporation ranges from 762 to 1,016 millimeters (30 to 40 inches). The mean annual air temperature ranges from 21 to 25 degrees C (70 to 77 degrees F). The mean annual soil temperature is 22 degrees C or higher (72 degrees F).

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ohia, Olaa, and Papai soils. Ohia soils are deep and very deep and non-skeletal. Olaa soils are moderately deep over `a`a lava. Papai soils are organic soils over fragmental `a`a.

DRAINAGE AND PERMEABILITY: Moderately well drained. Runoff is low. Permeability is moderate in the soil and very slow in the underlying bedrock.

USE AND VEGETATION: These soils are used principally for pasture and macadamia nut orchards. Vegetation is hilograss (Paspalum conjugatum), californiagrass (Urochloa mutica), lantana (Lantana camara), hapuu treefern (Cibotium glaucum), uluhe fern (Dicranopteris linearis) and guava (Psidium guajava).

DISTRIBUTION AND EXTENT: Island of Hawaii. This series is moderately extensive, with approximately 15,000 acres. MLRA 159A - Humid and Very Humid Volcanic Ash Soils on Low and Intermediate Rolling Mountain Slopes.

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

SERIES ESTABLISHED: Hawaii County, Hawaii, 1971.

REMARKS:
Last revised by state on 8/09 by PGN and AMS.

Diagnostic horizons and features (9th edition Keys to Soil Taxonomy) recognized in this pedon are:
Ochric epipedon - from 0 to 40 centimeters (0 to 16 inches).
Lithic contact - at 40 centimeters (16 inches).
Andic soil properties - from 0 to 40 centimeters (0 to 16 inches).
Isohyperthermic soil temperature regime.
Soil moisture precipitation exceeds evapotransporation in all months of normal years (perudic moisture regime).
ADDITIONAL DATA: NASIS User Pedon ID 05HI602316.

National Cooperative Soil Survey
U.S.A.