LOCATION PAPAA HIEstablished Series
TAXONOMIC CLASS: Fine, smectitic, isohyperthermic Typic Haplusterts
TYPICAL PEDON: Papaa clay - pasture. (Colors are for moist soil unless otherwise noted. All textures are "apparent field textures.")
Ap--0 to 12 inches; 1/2 to 1 inch thick very dark gray (10YR 3/1) surface mulch having moderate fine and very fine granular structure; very dark brown (10YR 2/2) clay, some dark brown (7.5YR 4/2); strong fine subangular blocky structure; hard, firm, very sticky and very plastic; many fine and medium roots; common fine and very fine tubular and interstitial pores; few worm holes; common fine, dark gray, highly weathered fragments of rock; common shiny specks; slight effervescence with hydrogen peroxide; slightly acid (pH 6.5); clear smooth boundary. (6 to 14 inches thick)
AC--12 to 19 inches; dark reddish brown (5YR 3/2) moist and dry clay; moderate coarse prismatic structure; hard, firm, very sticky and very plastic; many fine and medium roots; many very fine and few fine tubular pores; common worm holes and casts which are thickly coated with very dark gray (10YR 3/1 dry) gelatinous material; few fine angular fragments of rock; slight effervescence with hydrogen peroxide; slightly acid (pH 6.4); clear smooth boundary. (6 to 9 inches thick)
C1--19 to 24 inches; dark reddish gray (5YR 4/2) moist and dry clay; weak coarse prismatic structure; common prominent slickensides; hard, very firm, very sticky and very plastic; many fine and medium roots; common very fine and fine tubular pores; root channels lined with very dark gray (10YR 3/1) dry material; few fine fragments of rock; slight effervescence with hydrogen peroxide, slightly acid (pH 6.5); abrupt wavy boundary. (4 to 8 inches thick)
C2--24 to 28 inches; variegated pattern of grayish brown (10YR 5/2) and dark grayish brown (10YR 4/2) clay; strong coarse prismatic structure; many deeply grooved slickensides; extremely hard, firm very sticky and very plastic; many fine and medium roots; common fine and medium pores; peds coated with shiny specks; slightly acid (pH 6.3); abrupt wavy boundary. (2 to 10 inches thick)
C3--28 to 40 inches; mixture of brown (10YR 5/3), dark yellowish brown (10YR 4/4) and dark grayish brown (10YR 4/2) silty clay loam; massive; slightly hard, friable, slightly sticky and slightly plastic; common fine and medium roots; common fine tubular pores; few fine fragments of highly weathered rock; slightly acid (pH 6.5).
C4--40 inches; slightly to moderately weathered basalt.
TYPE LOCATION: Honolulu County, Hawaii; Koko Head Quadrangle - 21 degrees 22' 04" north latitude and 157 degrees 44' 11" west longitude; Kalanianaole Highway-Kailua Road junction; southeast on Kalanianaole Highway toward Waimanalo 1.5 miles to farm road; east on farm road 1,500 feet to a power line, under the power line 1/2 mile southeast from the intersection of the power line and the farm road.
RANGE IN CHARACTERISTICS: Depth to bedrock is 40 inches or more. The A horizon has hue of 5YR through 10YR, and value of 2 or 3 moist. The AC and C horizons have hue of 10YR through 5YR.
COMPETING SERIES: These are the Kapuhikani, Kokokahi, Lualualei, Makalapa and Nonopahu series. Kapuhikani soils are calcareous in the lower part of the C horizon, are dry for more than 6 months in most years, and are 24 to 36 inches deep over hard rock. Kokohahi soils have 2.5Y or yellower hue below the A horizon, and have chroma of 1 in the upper 12 inches. Lualualei soils have horizons high in gypsum at a depth of less than 40 inches. Makalapa soils formed in volcanic tuff and are strongly calcareous below a depth of 20 inches. Nonopahu soils have kaolinitic mineralogy and have moist value of 4 or more in the upper 12 inches.
GEOGRAPHIC SETTING: The Papaa soils are on uplands at elevations from near sea level to 500 feet. Slopes range from 6 to 70 percent. The dominant slopes are between 35 and 70 percent; smaller areas have gently rolling to hilly topography. Papaa soils formed in residuum weathered from basalt and colluvium. Annual rainfall is 30 to 45 inches, most of which falls during the winter. Mean annual temperature is about 73 degrees F., average January temperature is 71 degrees F., and average July temperature is 76 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Alaeloa soils, and the competing Kokohahi soils. Alaeloa soils have 2.5YR or redder hue below the A horizon.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff, depending on slope; slow permeability.
USE AND VEGETATION: Mainly unimproved pasture. Natural vegetation is guava (Psidium guajava). Java plum (Eugenia cumini), klu (Acacia farnesiana), koa-haole (Leucaena glauca), Christmasberry (Schinus terebinthifolis), lantana (Lantana camara), sensitive plant (Mimosa pudica), sourgrass (Trichachne insularis), ricegrass (Paspalum orbiculare), and oi (Stachytarpheta jamaicensis).
DISTRIBUTION AND EXTENT: Honolulu County, Hawaii, between Kaneohe Bay and Waimanalo. The extent is
about 1,100 acres.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Soil Survey, Territory of Hawaii, 1949.
OSED scanned by SSQA. Last revised by state on 5/78.