LOCATION WAHREKDAM          GU+FM HI PB
Established Series
RD:WEL
12/81

WAHREKDAM SERIES


The Wahrekdam series consists of moderately deep, well drained soils on uplands and ridgetops. These soils formed in residuum derived from basic igneous rock. Slope is 2 to 8 percent. The mean annual rainfall is about 145 inches, and the mean annual temperature is about 81 degrees F.

TAXONOMIC CLASS: Clayey-skeletal, oxidic, isohyperthermic,
shallow Plinthic Acrorthox

TYPICAL PEDON: Wahrekdam very gravelly sandy loam - on an 2 percent slope in agricultural forest. When described (1/24/79) the soil was moist throughout. (Colors are for moist soil. All textures are apparent field textures.)

A1--0 to 8 inches; dark brown (10YR 3/3) very gravelly sandy loam, moderate fine and medium granular structure; very friable, nonsticky and nonplastic; many fine and medium roots and common coarse roots; many very fine and fine interstitial pores; about 40 percent subrounded iron concretions .08 to .8 inch in diameter; and about 10 percent small angular basalt cobbles; medium acid (pH 6.0, 1:1 water); clear smooth boundary. (5 to 10 inches thick)

B1--8 to 17 inches; strong brown (7.5YR 5/6) very gravelly sandy clay loam; weak medium subangular blocky structure parting to moderate fine and medium granular; very friable, slightly sticky and slightly plastic; many fine and medium roots; common very fine and fine tubular pores and many very fine and fine interstitial pores; about 25 percent subrounded iron concretions .08 to .8 inch in diameter; 10 percent angular basalt pebbles, and 10 percent basalt cobbles; medium acid (pH 6.0, 1:1 water); gradual wavy boundary. (5 to 10 inches thick)

B2--17 to 29 inches; strong brown (7.5YR 5/8) very cobbly clay loam; weak coarse subangular blocky structure parting to moderate fine and medium granular; friable, slightly sticky and slightly plastic; few fine and medium roots; common very fine and fine tubular pores; common thin waxy coatings on faces of peds and in pores; about 20 percent iron concretions and 30 percent weathered basalt cobbles; medium acid (pH 5.8, 1:1 water); abrupt wavy boundary. (9 to 20 inches thick)

Cr--29 to 31 inches; yellowish red (5YR 4/6) platy weathering rind; crushes to silt loam; firm and brittle. (1 to 4 inches thick)
R--31 inches; fractured hard basalt; fracture seams are 8 to 23 inches apart and .4 to 1 inch wide and are filled with black manganese precipitates and weathering rinds.

TYPE LOCATION: Island of Ponape, Federated States of Micronesia; about 328 feet north of water tank on paved road and 67 feet west of road, in Nett Municipality; lat. 6 degrees 56 minutes 50.7 seconds N. and long. 158 degrees 13 minutes 20.3 seconds E.

RANGE IN CHARACTERISTICS: The thickness of the profile and of the solum ranges from 20 to 39 inches. The profile in 1:1 water is strongly acid or medium acid.

The A horizon has moist color of 10YR 3/2 or 3/3. It is sandy loam or sandy clay loam and has 15 to 50 percent pebbles and 0 to 20 percent cobbles.

The B Horizon has moist color of 7.5YR 4/6, 5/6, or 5/8, or of 10YR 4/4 or 4/6. It is sandy clay loam, clay loam, or sandy clay, and has 20 to 50 percent pebbles and 10 to 40 percent cobbles.

COMPETING SERIES: These are the Rakied and Umpump series in other families. Rakied soils are deep. Umpump soils are moderately deep over highly weathered basalt and are nonskeletal.

GEOGRAPHIC SETTING: Wahrekdam soils are on uplands and ridgetops. They formed in residuum derived from basic igneous rock. Slopes are 2 to 8 percent. Elevation is 49 to 984 feet. The mean annual rainfall is 143 to 196 inches, and the mean annual temperature is about 81 degrees F.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Umpump soils.

DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderately rapid permeability.

USE AND VEGETATION: Wahrekdam soils are used for subsistence agriculture and woodland. The main crops are banana, breadfruit, and coconut. The vegetation in areas not cultivated is mixed upland forest.

DISTRIBUTION AND EXTENT: On the islands of Ponape and Truk, East Caroline Islands. The series is of small extent.

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

SERIES ESTABLISHED: Ponape, Federated States of Micronesia, 1981.


National Cooperative Soil Survey
U.S.A.