LOCATION PAUMALU HIEstablished Series
TAXONOMIC CLASS: Very-fine, parasesquic, isohyperthermic Ustic Haplohumults
TYPICAL PEDON: Paumalu silty clay - pasture. (Colors are for moist soil unless otherwise noted. All textures are "apparent field textures.")
A1--0 to 9 inches; dark reddish brown (5YR 3/3) silty clay, reddish brown (5YR 4/3) dry; strong fine subangular blocky structure; hard, firm, sticky and plastic; many fine and medium roots; many very fine and fine interstitial and tubular pores; few highly weathered pebbles; very strongly acid (pH 5.0); abrupt smooth boundary. (8 to 12 inches thick)
B21--9 to 17 inches; dark reddish brown (5YR 3/4) silty clay, reddish brown (5YR 4/4) dry; moderate fine subangular blocky structure; hard, firm, sticky and plastic; many fine roots; common fine and very fine tubular pores; common black stains; few highly weathered pebbles; strongly acid (pH 5.3); clear smooth boundary. (5 to 9 inches thick)
B22t--17 to 33 inches; dark reddish brown (5YR 3/4) silty clay, reddish brown (5YR 4/4) dry; moderate very fine and fine angular and subangular blocky structure; hard, firm, sticky and plastic; few very fine roots; common very fine tubular pores; common stains as above; thin continuous clay films on peds and in pores; few highly weathered pebbles; medium acid (pH 5.9); gradual smooth boundary. (10 to 16 inches thick)
B31t--33 to 48 inches; same color, texture and consistence as above; strong fine blocky structure; few fine roots; few fine tubular pores; thin continuous clay films on peds and in pores that are dark red (2.5YR 3/6); common highly weathered pebbles; medium acid (pH 5.9); clear wavy boundary. (12 to 15 inches thick)
B32--48 to 70 inches; same as above except no roots, and the horizon contains 40 to 50 percent highly weathered basalt gravel.
TYPE LOCATION: Honolulu County, Hawaii; Sunset Beach area; Kahuku Quadrangle - 21 degrees 40' 18" north latitude and 158 degrees 01' 02'' west longitude; at the intersection of the Pupukea Homestead road and the Kamehameha Highway north of Waimea Bay, proceed toward Kahuku 3.1 miles to the military access road; proceed up military road toward Kaunala Ridge 1.65 miles; site is 25 feet west of access road.
RANGE IN CHARACTERISTICS: Depth to highly weathered gravel ranges from 30 to more than 60 inches. Mean annual soil temperature is about 72 degrees F. Effervescence with hydrogen peroxide ranges from none to moderate in the 4 horizon. Moist value of the B horizon is 3 or 4 and chroma is 4 through 6 moist or dry.
COMPETING SERIES: These are the Alaeloa, Kalapa, and Pauwela series. Alaeloa soils have 2.5YR or redder hue, strong structure in the argillic horizon, and thick continuous clay films in the lower part of the argillic horizon. Kalapa soils have clay texture and moderately thick clay films in the lower part of the argillic horizon. Pauwela soils have high bulk density and 10YR or 2.5YR hue in the A horizon and moderately thick clay films in the argillic horizon.
GEOGRAPHIC SETTING: Paumalu soils are on uplands at elevations from 700 to 1,000 feet. Slopes range from 3 to 70 percent. The soils formed in residuum and colluvium from basic igneous rock. Annual rainfall is 50 to 70 inches. Average January temperature is about 68 degrees F.; average July temperature is about 74 degrees F.; and mean annual temperature is about 72 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Kemoo and Wahiawa soils. Kemoo soils have 2.5YR or redder hue in the argillic horizon. Wahiawa soils lack an argillic horizon and have 2.5YR or redder hue throughout the solum.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderately rapid permeability.
USE AND VEGETATION: Used mainly for pasture, but a small acreage is used for pineapple and sugarcane. Vegetation is guava (Psidium guajava), waiwe (Psidium cattleianum lucidum), creeping Chinese violet (Centella asiatica), Christmasberry (Schinus terebinthifolius), ricegrass (Paspalum orbiculare), and carpetgrass Axonopus affinis).
DISTRIBUTION AND EXTENT: Northern part of the lower slopes of the Koolau Range east of Sunset Beach above Kahuku to Kahana Bay on the island of Oahu, Hawaii. The soils are of small extent comprising about 7,900 acres.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Honolulu County, Island of Oahu, 1971.
OSED scanned by SSQA. Last revised by state on 5/78.