LOCATION WAAWAA HITentative Series
TAXONOMIC CLASS: Medial, amorphic, isothermic Pachic Haplustands
TYPICAL PEDON: Waawaa medial silt loam, on a west facing, slightly convex, 2 percent slope under pasture at an elevation of 1158 meters (3,800 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 July 22, 1993, the soil was moist throughout.)
A--0 to 20 centimeters (0 to 8 inches); dark brown (7.5YR 3/2) medial silt loam, dark brown (7.5YR 3/3) dry; moderate fine subangular blocky structure; friable, slightly sticky and slightly plastic; many fine and medium roots; few very fine interstitial pores; neutral (pH 7.0); abrupt wavy boundary. (18 to 20 centimeters {7 to 8 inches} thick)
Bw1--20 to 28 centimeters (8 to 11 inches); dark reddish brown (5YR 3/2) medial silty clay loam, dark reddish brown (5YR 3/4) dry; weak fine and medium subangular blocky structure; friable, slightly sticky and slightly plastic; many fine and common medium roots; common very fine interstitial pores; neutral (pH 7.1); clear wavy boundary.
Bw2--28 to 43 centimeters (11 to 17 inches); dark reddish brown (5YR 3/2) medial silty clay loam, dark yellowish brown (10YR 3/4) dry; weak fine and medium subangular blocky structure; friable slightly sticky and slightly plastic; many fine and common medium roots; common very fine interstitial pores; neutral (pH 7.1); gradual smooth boundary.
Bw3--43 to 58 centimeters (17 to 23 inches); dark reddish brown (5YR 3/2) medial silty clay loam, dark yellowish brown (10YR 3/4) dry; weak fine and medium subangular blocky structure; firm, sticky and slightly plastic; common fine and medium roots; common very fine and few fine interstitial pores; 5 percent subangular gravel; neutral (pH 7.1); clear wavy boundary.
Bw4--58 to 79 centimeters (23 to 31 inches); dark reddish brown (5YR 3/2) medial silty clay loam, dark yellowish brown (10YR 3/4) dry; weak medium subangular blocky structure; friable, sticky and slightly plastic; few fine and common medium roots; common very fine and few fine interstitial pores; 5 percent subangular gravel; neutral (pH 7.2); clear wavy boundary. (Combined thickness of the Bw horizon ranges from 58 to 132 centimeters {23 to 52 inches}.)
2C--79 to 102 centimeters (31 to 40 inches); dark brown (7.5YR 3/2) gravelly medial silty clay loam, dark yellowish brown (10YR 3/6) dry; massive; firm, sticky and plastic; few fine and medium roots; common very fine and fine interstitial pores; 25 percent subangular gravel; neutral (pH 7.2); clear wavy boundary. (15 to 25 centimeters {6 to 10 inches} thick)
3Ab--102 to 112 centimeters (40 to 44 inches); dark brown (7.5YR 3/3) medial silty clay loam, strong brown (7.5YR 4/6) dry; massive; firm, sticky and slightly plastic; few medium roots; many very fine and common fine interstitial pores; neutral (pH 7.1); clear wavy boundary. (8 to 13 centimeters {3 to 5 inches} thick)
3Bwb1--112 to 119 centimeters (44 to 47 inches); reddish brown (5YR 4/4) medial silty clay loam; massive; friable, sticky and slightly plastic; few medium roots; many very fine and common fine interstitial pores; neutral (pH 7.1); clear wavy boundary.
3Bwb2--119 to 152 centimeters (47 to 60 inches); dark reddish brown (5YR 3/4) medial silty clay loam; massive; friable, sticky and slightly plastic; few medium roots; many very fine and common fine interstitial pores; neutral (pH 7.1).
TYPE LOCATION: Island of Hawaii, Hawaii County, Hawaii; on the east summit of Pu`u Wa`awa`a, on Pu`u Wa`awa`a Ranch; Puu Anahulu Quadrangle; lat. 19 degrees 46 minutes 32.3 seconds N. and long. 155 degrees 50 minutes 3.8 seconds W. (Old Hawaiian Datum)
RANGE IN CHARACTERISTICS:
Depth to bedrock: More than 152 centimeters (60 inches).
Mean annual soil temperature: 18 to 22 degrees C. (65 to 72 degrees F.)
A horizon
Hue: 7.5YR or 10YR.
Value: 2 or 3 moist or dry.
Chroma: 1 or 2 moist, 3 or 4 dry.
Texture: Medial silt loam or gravelly medial silt loam.
Structure: Moderate subangular blocky or strong granular.
Soil reaction: Slightly acid or neutral (pH 6.1 to 7.3).
Bw horizon
Hue: 5YR to 10YR.
Value: 3 or 4 moist, 3 to 5 dry.
Chroma: 2 to 4 moist or dry.
Structure: Weak or moderate subangular blocky.
Soil reaction: Neutral or slightly alkaline (pH 6.6 to 7.8).
2C horizon
Hue: 7.5YR or 10YR.
Value: 3 to 5 moist, 5 to 7 dry.
Chroma: 2 or 3 moist or 4 to 6 dry.
Texture: Very gravelly medial silty clay loam or extremely gravelly medial sand.
Structure: Massive or single grain.
Soil reaction: Neutral or slightly alkaline (pH 6.6 to 7.8).
3Ab horizon
Hue: 7.5YR or 10YR.
Value: 3 or 4 moist or dry.
Chroma: 3 or 4 moist, 5 or 6 dry.
Structure: Massive or weak very fine and fine subangular blocky.
Soil reaction: Neutral or slightly alkaline (pH 6.6 to 7.8).
3Bwb horizon
Hue: 5YR to 10YR.
Value: 3 or 4 moist, 4 or 5 dry.
Chroma: 3 or 4 moist, 4 or 5 dry.
Structure: Massive or weak very fine and fine subangular blocky.
Soil reaction: Neutral or slightly alkaline (pH 6.6 to 7.8).
COMPETING SERIES: There are no competing series. Similar soils include Akahipuu and Halekula soils. Akahipuu and Halekula soils are medial-skeletal, have a lithic contact at 50 to 102 centimeters (20 to 40 inches), and overlie `a`a lava.
GEOGRAPHIC SETTING: Waawaa soils are on Pu`u Wa`awa`a cinder cone and associated trachyte flow on mid elevation, leeward slopes of Hualalai Volcano at elevations from 457 to 1210 meters (1500 to 3970 feet). These soils are on all hillslope positions of constructional landscapes that are greater than 100,000 years old. Slope gradients range from 2 to 70 percent and are nearly level to very steep. The soils formed in basic volcanic ash and cinders. The mean annual rainfall ranges from 380 to 760 millimeters (15 to 30 inches), with most of the rainfall occurring from January through July. The mean annual pan evaporation ranges from 1520 to 1780 millimeters (60 to 70 inches). The mean annual air temperature ranges from 17 to 21 degrees C. (63 to 70 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 Kahaumanu, Napuu, and Puuikaaka series, and the similar Akahipuu series. Kahaumanu and Napuu soils have a lithic contact at 25 to 50 centimeters (10 to 20 inches). Puuikaaka soils have a lithic contact at 5 to 25 centimeters (2 to 10 inches).
DRAINAGE AND PERMEABILITY: Well drained. Runoff is very low to high depending on slope. Permeability is moderately rapid.
USE AND VEGETATION: Used for grazing and homesite development. The natural vegetation is kikuyugrass (Pennisetum clandestinum), fountaingrass (Pennisetum setaceum), ohia lehua (Metrosideros polymorpha), and lantana (Lantana camara).
DISTRIBUTION AND EXTENT: North Kona District, Island of Hawaii; MLRA 161. 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 of July through January in most years (Ustic moisture regime).
Diagnostic horizons and features recognized in this pedon are:
Andic soil properties - from 0 to 132 centimeters (0 to 52 inches) (A, Bw, 2C, 3Ab, and 3Bwb horizons).
Mollic epipedon - from 0 to 79 centimeters (0 to 31 inches) (A and Bw horizons).
Cambic horizon - from 112 to 132 centimeters (44 to 52 inches) (3Bwb horizon).
Edit log: 4/09 MRK. Andic textural modifiers added plus minor edits.