LOCATION BANADERU MP+PBEstablished Series
TAXONOMIC CLASS: Clayey, parasesquic, isohyperthermic Lithic Argiustolls
TYPICAL PEDON: Banaderu clay loam, on a 10 percent southeasterly slope under secondary forest. (Colors are for moist soil unless otherwise stated.)
0i-1 to 0 inches; undecomposed leaf litter; clear smooth boundary. (0 to 2 inches thick)
Al-0 to 1 inch; black (N2/0) clay loam, dark reddish brown (5YR 2.5/2) dry; strong very fine granular structure; slightly hard, friable, nonsticky and slightly plastic; many very fine, fine and few medium roots; many very fine interstitial pores; about 10 to 20 percent sand-sized nodules which can be crushed; occasional cobbles; neutral (pH 7.0); abrupt boundary. (1 to 2 inches thick)
Bt1--1 to 7 inches; black (5YR 2.5/1) clay loam, dark reddish brown (5YR 3/2) dry; strong fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, fine and few medium roots; many very fine interstitial pores; about 10 to 20 percent sand-sized nodules which can be crushed; occasional cobbles; mildly alkaline (pH 7.4); clear wavy boundary. (4 to 6 inches thick)
Bt2--7 to 16 inches; dusky red (10R 3/4) clay, weak red (10R 4/4) dry; moderate very fine and fine subangular blocky structure, with a subrounded blocky microstructure of aggregates 1 to 2 millimeters in diameter; hard, friable, sticky and plastic; common very fine, few fine and medium roots; common very fine, fine and few medium tubular pores; few moderately thick clay films line pores and common thin clay films on ped faces; few very fine manganese concretions; mildly alkaline (pH 7.4); gradual wavy boundary. (3 to 9 inches thick)
Bt3--16 to 20 inches; dark red (10R 3/6) clay; weak fine subangular blocky structure; hard, friable, very sticky and plastic; common very fine and few fine roots; common very fine, fine and few medium tubular pores; many thin, common moderately thick and few thick pressure faces; very few intermittent areas with common thin dark grayish brown (10YR 4/2) clay films on ped faces and many thin, sugary, reddish yellow (7.5YR 6/8) coatings line pores; few very fine manganese concretions; mildly alkaline (pH 7.6); abrupt broken boundary. (2 to 4 inches thick)
2R--20 inches; jagged, irregular white limestone as pinnacles, with many holes and fissures.
TYPE LOCATION: Saipan, Commonwealth of the Northern Mariana Islands. West of the summit of Suicide Cliff, about 330 yards west on the Banaderu Trail, about 9 yards south of trail; lat. 15 degrees 16 minutes 40 seconds N. and long. 145 degrees 48 minutes 25 seconds E.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually dry for 90 to 120 cumulative days. Soil is usually moist from July through December.
Soil temperature - 77 to 84 degrees F., with less than 4 degrees F. variation between summer and winter.
Mollic epipedon thickness - 7 to 9 inches. Some pedons have A horizons as shallow as 4 inches, but the upper portion of the Bt horizon qualifies as a mollic epipedon.
Depth to bedrock - 10 to 20 inches.
Clay content - 40 to 60 percent in the argillic horizon.
A horizon - Color: N2/0, 5YR 2.5/1, 3/2, 3/3, 2.5YR 3/2, 10YR 3/2. Mixed texture: Clay loam or clay.
Structure: Granular or subangular blocky.
Rock fragments: 5 to 20 percent, about one-half as cobbles, with occasional stones.
B horizon - Color: Dominantly 10R 3/4 3/6, but ranges to 2.5YR 3/4 3/6.
Texture: Clay loam or clay.
Structure: Prismatic or subangular blocky.
Rock fragments: 0 to 10 percent, mostly as angular cobbles.
Other features: Coatings on ped faces and pores with colors different than the matrix are not present in all pedons. Colors of coatings include matrix colors, and also 10YR 4/2, 5YR 4/6, 7.5YR 6/8.
COMPETING SERIES: These are the Chinen, Luta, and Takpochao soils. The Chinen soils have B horizon hues of 5YR or yellower. Luta soils have yellower hues in the B horizon and oxidic mineralogy. Takpochao soils are clayey-skeletal, have B horizons with hues of 5YR or yellower, and lack an argillic horizon.
GEOGRAPHIC SETTING: Banaderu soils are on uplifted limestone plateaus that are often concave and tilted. They formed in sediments, possibly volcanic ash, that overlie relatively pure, porous coralline limestone. Slopes are dominantly 3 to 15 percent, but range from 3 to 30 percent. Elevation is 328 to 820 feet. Mean annual temperature is 77 degrees F., with less than 4 degrees F. difference between summer and winter. Mean annual precipitation is 80 to 90 inches, most of which falls between June and November.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chinen, Saipan and Takpochao soils. Chinen soils have B horizon hues of 5YR and yellower. Saipan soils are deep and very deep. Takpochao soils do not have pockets of soil that extend below a depth of 20 inches, and have an intermittent B horizon with hues of 5YR or yellower.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is slow to medium. Permeability is moderate.
USE AND VEGETATION: Most areas are in forest dominated by Leucaena leucocephala. Some areas are farmed.
DISTRIBUTION AND EXTENT: Banaderu soils are on the islands of Saipan and Tinian. This series is not extensive, with less than 2,470 acres mapped.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Saipan, Commonwealth of the Northern Mariana Islands, 1985.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - From the surface to a depth of 7 inches (A1 and upper Bt horizons). If pedons with slightly thinner horizons are mixed to a depth of 7 inches, the color and organic-carbon content qualify as a mollic epipedon.
Argillic horizon - from the top of the Bt horizon to the lithic contact.