LOCATION NANSEPSEP FM+PBEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, nonacid, isohyperthermic Mollic Endoaquepts
TYPICAL PEDON: Nansepsep silt loam - coconut and banana. When described (6/4/79) the soil was moist to a depth of 27 inches and saturated below. (Colors are for moist soil. All textures are apparent field textures.)
A1--0 to 4 inches; dark brown (7.5YR 3/2) silt loam; moderate fine angular blocky structure; friable, slightly sticky and slightly plastic; common very fine and fine roots and medium roots; common very fine and fine tubular and interstitial pores; medium acid (pH 5.6, 1:1 water in place); abrupt wavy boundary. (3 to 8 inches thick)
B1--4 to 9 inches; dark brown (7.5YR 3/4) silt loam; moderate fine and medium subangular blocky structure; friable, slightly sticky and slightly plastic; common very fine and fine roots and few medium roots; common very fine and fine tubular pores; medium acid (pH 5.6, 1:1 water); gradual wavy boundary. (3 to 10 inches thick)
B21--9 to 20 inches; dark grayish brown (2.5Y 4/2) silty clay loam; common fine distinct mottles of strong brown (7.5YR 4/6); moderate fine and medium angular blocky structure; friable, slightly sticky and slightly plastic; few very fine and fine roots and medium roots, many very fine and fine tubular pores; medium acid (pH 6.0, 1:1 water); abrupt wavy boundary. (8 to 18 inches thick)
B22--20 to 31 inches; dark grayish brown (2.5Y 4/2) silty clay loam; many fine distinct strong brown (7.5YR 4/6) mottles; moderate fine and very fine angular blocky structure; friable, sticky and plastic; few very fine and fine roots; common fine tubular pores; medium acid (pH 6.0, 1:1 water) gradual wavy boundary. (8 to 20 inches thick)
B23--31 to 39 inches; dark grayish brown (2.5Y 4/2) silty clay loam; medium distinct strong brown (7.5YR 4/6) mottles; weak fine and medium angular blocky structure; friable, sticky and plastic; few very fine and fine roots; common fine tubular pores; slightly acid (pH 6.2, 1:1 water); abrupt smooth boundary. (0 to 10 inches thick)
Cg--39 to 59 inches; dark greenish gray (5GY 4/1) silty clay loam; weak fine and medium angular blocky structure; friable, sticky and plastic; common very fine tubular pores; slightly acid (pH 6.2, 1:1 water).
TYPE LOCATION: Island of Ponape, Federated States of Micronesia; 164 feet south of the second bridge of Alokapw and 49 feet west of the road in the municipality of Madolenihmw; lat. 6 degrees 55 minutes 5 seconds N. and long. 158 degrees 17 minutes 46 seconds E.
RANGE IN CHARACTERISTICS: Depth to the fluctuating water table ranges from 20 to 29 inches. The soil is medium acid or slightly acid.
The A horizon has moist color of 10YR 3/2 or 3/3 or of 7.5YR 3/2. It is silt loam or silty clay loam and has 0 to 15 percent pebbles.
The B horizon has moist color of 10YR 4/2, 5/2, or 5/3, of 7.5YR 3/4 or 4/4, or of 2.5Y 4/2. It has mottles of 10YR 4/6 or of 7.5YR 4/6 or 5/6. It is silt loam, silty clay loam, or silty clay and has 0 to 15 percent pebbles.
The C horizon is gleyed silty clay or silty clay loam and is 0 to 25 percent basalt pebbles.
COMPETING SERIES: These are the Inkosr and Insak series. Inkosr soils are poorly drained. Insak soils are sandy.
GEOGRAPHIC SETTING: Nansepsep soils are on bottomlands. They formed in alluvium derived from basic igneous rock. Slopes are 0 to 2 percent. Elevation ranges from 6 to 328 feet. The mean annual rainfall is 157 to 196 inches, and the mean annual temperature is about 81 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Sonahnpil and the competing Inkosr soils. Sonahnpil soils are well drained and very stony.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow runoff; moderate permeability. The soils are flooded occasionally for very brief periods in any month. The water table is at a depth of 20 to 29 inches throughout the year.
USE AND VEGETATION: Nansepsep soils are used for subsistence agriculture. The main crops grown are banana and coconut.
DISTRIBUTION AND EXTENT: On the islands of Kosrae and Ponape, 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.