LOCATION ARAWAK VIEstablished Series
TAXONOMIC CLASS: loamy-skeletal, carbonatic, isohyperthermic, shallow Typic Haplustolls
TYPICAL PEDON: Arawak gravelly loam. (Colors are for moist conditions.)
A1--0 to 6 inches; very dark grayish brown (10YR 3/2) gravelly loam; strong medium and coarse granular structure; friable; common fine and medium roots; about 30 percent, by volume, limestone pebbles; strongly effervescent; moderately alkaline; clear wavy boundary. (4 to 12 inches thick)
A2--6 to 11 inches; very dark grayish brown (10YR 3/2) very gravelly loam; strong medium granular structure; friable; common fine and medium roots; common fine and medium soft masses of calcium carbonate; about 50 percent, by volume, limestone pebbles; strongly effervescent; moderately alkaline; gradual wavy boundary. (2 to 6 inches thick)
C--11 to 14 inches; pale brown (10YR 6/3) very gravelly loam; massive; friable; few fine and medium roots; common fine and medium soft masses of calcium carbonate; about 50 percent, by volume, limestone pebbles and cobbles; strongly effervescent; moderately alkaline; gradual wavy boundary. (1 to 6 inches thick)
Cr1--14 to 23 inches; pale brown (10YR 6/3) and pinkish white (7.5YR 8/2) soft limestone bedrock; massive; few fine roots in fractures; strongly effervescent; moderately alkaline; diffuse wavy boundary.
Cr2--23 to 30 inches; pale brown (10YR 6/3)soft limestone bedrock; massive; few fine roots in fractures; strongly effervescent; moderately alkaline; diffuse wavy boundary.
Cr3--30 to 60 inches; pale brown (10YR 6/3) and pinkish white (7.5YR 8/2) soft limestone bedrock; massive; strongly effervescent; moderately alkaline.
TYPE LOCATION: St. Croix Island, U.S. Virgin Islands. Constitution Hill area; from the intersection of VI-708 and VI-811, 0.1 mile Northwest on VI-811, 0.1 mile east on side slope. Christiansted topographic quadrangle; lat. 17 degrees 44 minutes 13 seconds N.; long. 64 degrees 43 minutes 54 seconds W.; PRD 1940.
RANGE IN CHARACTERISTICS: Depth to soft limestone ranges from 10 to 20 inches. Reaction is moderately alkaline throughout. Rock fragments include pebbles, cobbles, flags, and boulders composed of limestone or coral.
The A horizon has hue of 7.5YR or 10YR, value of 2 or 3, and chroma of 2 or 3. Texture is clay loam or loam in the fine-earth fraction. Content of rock fragments range from 15 to 60 percent by volume.
The C horizon has hue of 7.5YR or 10YR, value of 3 to 8, and chroma of 1 to 4. Texture is loam or sandy loam in the fine-earth fraction. Soft masses of calcium carbonate range from few to many. Content of rock fragments range from 35 to 60 percent by volume.
The Cr horizon is composed of soft limestone. It has hue of 7.5YR or 10YR, value of 5 or 6, and chroma of 1 to 4; or it has no dominant matrix color and the horizon is multicolored in shades of pink, white, and brown.
COMPETING SERIES: There are no competing series in the same family.
GEOGRAPHIC SETTING: Arawak soils are on summits and side slopes of limestone hills and mountains. They formed in material weathered from soft limestone bedrock. Slopes range from 2 to 70 percent. The climate is tropical semiarid. The average annual temperature ranges from 76 to 82 degrees F., and the mean annual precipitation is about 40 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the Glynn, Hesselberg, Hogensborg, and Sion soils. All of these soils are on lower positions. In addition, Glynn soils are very deep and have clayey-skeletal particle-size control sections. Hesselberg soils have petrocalcic horizons. Hogensborg soils are very deep, and have fine, smectitic particle-size control sections. Sion soils are very deep and have coarse-loamy particle-size control sections.
DRAINAGE AND PERMEABILITY: Well drained; slow permeability.
USE AND VEGETATION: Most areas of Arawak soils are used for pastureland or rangeland. Some areas have been converted to residential and urban development. Vegetation consists of grasses and shrubs.
DISTRIBUTION AND EXTENT: St. Croix Island, U.S. Virgin Islands. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina
SERIES ESTABLISHED: St. Croix, U.S.V.I., 1995.
REMARKS: These soils were mapped as Aguilita series in the 1970 soil survey of the Virgin Islands. Diagnostic horizons and other features recognized in this pedon include:
Mollic epipedon - zone from 0 to 11 inches (A and AB horizons)
Skeletal feature - more than 35 percent weighted average rock fragments in the particle-size control section.
Paralithic contact - 14 inches.
ADDITIONAL DATA: Characterization pedon - St. Croix Island, U.S. Virgin Islands; S92VI-10-8. Sample by NSSL, Lincoln NE., 1992.
MLRA: 273.