LOCATION SONGSONG MP PBTentative Series
TAXONOMIC CLASS: Medial over ashy-pumiceous or ashy-skeletal, glassy, isohyperthermic Typic Ustivitrands
TYPICAL PEDON: Songsong loam, on a south facing, 10 percent slope in a jungle of tangantangan, hibiscus and coconut trees at an elevation of 9 meters (30 feet). (Colors are for moist soil unless otherwise noted. When described on June 12, 1999 the soil was moist throughout).
A--0 to 15 cm (0 to 6 in); black (2.5Y 2.5/1) interior, ashy loam; weak fine subangular blocky and weak medium subangular blocky parting to weak fine granular structure; friable, soft, nonsticky, nonplastic; moderately smeary; many very fine, many fine, common medium, and common coarse roots throughout; 10 percent angular 2 to 75mm cinders; slightly acid, pH 6.3; gradual wavy boundary. 8 to 28 centimeters thick (3 to 11 inches).
Bw1--15 to 30 cm (6 to 12 in); olive brown (2.5Y 4/3) interior, very gravelly ashy loamy coarse sand; weak fine subangular blocky parting to weak fine granular structure; loose, loose, nonsticky, nonplastic; common fine roots throughout and common very fine roots throughout; 50 percent angular 2 to 75mm cinders; neutral, pH 7.3; clear wavy boundary; 5 to 25 centimeters thick (2 to 10 inches).
Bw2--30 to 48 cm (12 to 19 in); olive brown (2.5Y 4/4) interior, very gravelly ashy coarse sand; weak fine subangular blocky and weak medium subangular blocky parting to weak fine granular structure; loose, loose, nonsticky, nonplastic; common fine and common medium roots throughout; 10 percent subangular 2 to 20 mm strongly cemented tuff fragments; 45 percent angular 2 to 75 mm cinder fragments; slightly alkaline, pH 7.4; clear smooth boundary; there is a laminar cemented layer within this layer angled at 40 degrees; 8 to 67 centimeters thick (3 to 27 inches).
2C--48 to 66 cm (19 to 26 in); 20 percent lithochromic dark grayish brown (10YR 4/2) interior and 80 percent lithochromic dark gray (10YR 4/1) interior, stratified very gravelly ashy coarse sand; massive; firm, hard, nonsticky, nonplastic; 35 percent subrounded 2 to 75 mm cinders; neutral, pH 7.3; gradual wavy boundary; 15 to 30 centimeters thick (6 to 12 inches).
3C--66 to 203 cm (26 to 80 in); 20 percent lithochromic dark grayish brown (10YR 4/2) interior and 80 percent lithochromic dark gray (10YR 4/1) interior, stratified very gravelly ashy coarse sand; structure; loose, loose, nonsticky, nonplastic; 45 percent subrounded 2 to 75 mm cinders; neutral, pH 7.2; 48 to 137 centimeters thick (19 to 54 inches).
TYPE LOCATION: Island of Agrihan, Commonwealth of the Northern Mariana Islands, approximately 457 meters (1500 feet) northeast of the well, Songsong Village; lat. 18 degrees, 44 minutes and 19 seconds north; long. 145 degrees, 39 minutes, and 39 seconds east; NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is moist in some part from July through November and much drier from December through June.
Reaction: The soil is slightly acid to slightly alkaline.
Depth to cemented tuff fragments: 30 to 48 centimeters (12 to 19 inches)
Particle-size control section:
Rock fragments: 5 to 55 percent 2 to 75 mm cinders in any horizon
but weighted average is 35 to 55 percent
Pararock fragments: 10 to 30 percent 5 to 20 mm cemented tuff fragments
A horizon:
Hue: 10YR or 2.5Y
Value: 2.5 to 5
Chroma: 1 or 2
Texture: ashy modifiers of gravelly and very gravelly coarse sand, very
coarse sand, very fine sand, loamy fine sand, fine sandy loam,
coarse sandy loam, loam and silt loam
Rock fragments: 5 to 15 percent 2 to 75 mm cinders
Reaction: slightly acid or neutral
B horizons:
Hue: 7.5YR, 10YR or 2.5Y
Value: 4 or 5
Chroma: 1 through 5
Texture: ashy modifiers of very gravelly coarse sand, loamy sand, loam
Rock fragments: 15 to 55 percent gravel cinders
Pararock fragments: 10 to 30 percent 5 to 20 mmcemented tuff fragments
Reaction: neutral to slightly alkaline
C horizons:
Hue: 10YR or 2.5Y
Value: 3 to 5
Chroma: 1 through 4
Texture: ashy modifiers of extremely gravelly coarse sand and very gravelly
coarse sand,
Rock fragments: 35 to 65 percent 2 to 75mm cinders
COMPETING SERIES: There are no other soils in this family.
GEOGRAPHIC SETTING:
Parent material: volcanic ash and cinders derived from basalt and andesite deposited through alluvial and colluvial processes
Landform: dissected alluvial terraces and steep remnant terraces
Slopes: 0 to 100 percent
Elevation: 6 to 304 meters (20 to 1000 feet)
Mean annual temperature: 26 to 30 degrees C. (79 to 86 degrees F.)
The mean annual soil temperature: about 28 degrees C. (83 degrees F.)
Mean annual precipitation: 1780 to 2290 millimeters (70 to 90 inches)
Precipitation pattern: Tropical, characterized by a wet season from July through November when moderate or torrential rains occur, and a dry season when substantially less precipitation from December through June is received.
Frost-free period: 365 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Apilam and the Hatisu soils. Both Apilam and Haitisu soils have finer textures in the solum and Apilam soils have seasonal densic layers.
DRAINAGE AND PERMEABILITY: Well drained, low to medium runoff, and moderate permeability.
USE AND VEGETATION: These soils are used for agroforestry, mixed agriculture, and beef, goat and hog grazing. Native and naturalized vegetation includes short grasses, coconut palms, hibiscus, breadfruit, giant tangantangan, and fish-kill tree.
DISTRIBUTION AND EXTENT: Northern Mariana Islands. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Island of Agrihan, Commonwealth of the Northern Mariana Islands.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: The zone from 0 to 15 centimeters (0 to 40 inches).
Andic properties: The zone from 0 to 48 centimeters (0 to 19 inches).
Particle-size control section: The zone from 0 to 100 centimeters (0 to 40 inches).
Remarks: In some pedons redoximorphic features occur at about 30 to 48 centimeters (12 to 19 inches).
Taxonomic Version: Second edition Soil Taxonomy, 1999.
ADDITIONAL DATA: NSSL lab soil survey sample #S99PB-646-003 (type location); #S99MP-090-084; S99PB-646-001; S99PB-646-002