LOCATION PARASOL VIEstablished Series
TAXONOMIC CLASS: Fine, smectitic, isohyperthermic Typic Argiustolls
TYPICAL PEDON: Parasol clay loam. (Colors are for moist conditions.)
A1--0 to 7 inches; very dark brown (10YR 2/2) clay loam; strong fine and medium granular structure; firm, moderately sticky, moderately plastic; many fine and medium roots, few coarse roots; many medium and coarse interstitial pores; many medium and coarse wormcasts; about 5 percent, by volume, pebbles; slightly acid; clear wavy boundary.
A2--7 to 13 inches; very dark brown (10YR 2/2) clay loam; strong medium granular structure; firm, moderately sticky, moderately plastic; common fine and medium roots; many medium and coarse interstitial pores; many medium and coarse wormcasts; about 5 percent, by volume, pebbles; neutral; clear smooth boundary. (Combined thickness of the A horizons is 4 to 18 inches.)
Bt1--13 to 19 inches; brown (10YR 4/3) clay loam; strong medium and coarse prismatic structure; firm, moderately sticky, moderately plastic; few fine and medium roots; few distinct pressure faces on vertical and horizontal ped faces; common fine and medium vesicular and tubular pores; many fine and medium wormcasts; common fine faint clay films on faces of peds; about 5 percent, by volume, pebbles; neutral; gradual smooth boundary.
Bt2--19 to 24 inches; brown (10YR 4/3) sandy clay loam; moderate medium and coarse prismatic structure; friable; slightly sticky, slightly plastic; few fine roots; few fine and medium vesicular and tubular pores; common fine and medium wormcasts; few fine faint clay films on paces of peds; few fine clay films on faces of peds; about 5 percent, by volume, pebbles; neutral; gradual smooth boundary. (Combined thickness of the Bt horizons is 8 to 12 inches.)
BC--24 to 40 inches; dark yellowish brown (10YR 4/4) sandy clay loam; weak fine and medium subangular blocky structure; friable, slightly sticky, slightly plastic; about 10 percent, by volume, pebbles; few fine distinct strong brown (7.5YR 5/8) masses of iron accumulation; neutral; gradual smooth boundary. (8 to 18 inches thick)
C1--40 to 52 inches; brown (10YR 4/3) saprolite that has a sandy loam texture; massive; very friable; few medium feldspar crystals; neutral; gradual smooth boundary.
C2--52 to 62 inches; brown (10YR 4/3) saprolite that has a sandy loam texture; massive; very friable; common medium feldspar crystals; neutral; gradual smooth boundary.
C3--62 to 80 inches; brown (10YR 5/3) saprolite that has a sandy loam texture; massive; very friable; neutral. (Combined thickness of the C horizons is 8 to 20 inches.)
TYPE LOCATION: St. Croix Island, U.S. Virgin Islands. Approximately 0.4 mile northeast on VI-69 from River to 90-degree northwest bend in the highway, about 0.5 mile northwest along the highway, and about 300 feet northeast of the highway in a pasture. Christiansted topographic quadrangle; lat. 17 degrees 45 minutes 4 seconds N.; long. 68 degrees 49 minutes 9 secounds W.; PRD 1940.
RANGE IN CHARACTERISTICS: Thickness of the solum ranges from 24 to 48 inches. Reaction ranges from strongly acid to neutral in the A horizon, slightly acid to neutral in the Bt and BC horizons, and neutral to slightly alkaline in the C horizons.
The A horizon has hue of 7.5YR or 10YR, value of 2 or 3, and chroma of 1 to 3. Texture is sandy clay loam or clay loam in the fine-earth fraction. Content of pebbles ranges from 0 to 15 percent, by volume.
The Bt horizon has hue of 10YR, value of 3 to 5, and chroma of 3 to 6. Masses of iron accumulations in shades of brown range from none to common. Texture is sandy clay loam, clay loam, or clay in the fine-earth fraction. Content of pebbles ranges from 0 to 30 percent, by volume.
The BC horizon has hue of 7.5YR to 2.5Y, value of 3 to 5, chroma of 2 to 8. Masses of iron accumulations in shades of brown range from none to common. Texture is sandy loam, sandy clay loam, or clay loam in the fine-earth fraction. Content of pebbles ranges from 0 to 30 percent, by volume.
The C horizon is saprolite. It has hue of 10YR or 2.5Y, value of 4 or 5, chroma of 2 to 4. Texture is loamy sand, sandy loam, or sandy clay loam in the fine-earth fraction.
COMPETING SERIES: There are no competing series in the same family.
GEOGRAPHIC SETTING: The Parasol soils are on side slopes and foot slopes of volcanic hills and mountains. They formed in plutonic residuum. Slopes range from 2 to 12 percent. The climate is tropical semiarid. The average annual air temperature ranges from 76 to 82 degrees F., and the mean annual precipitation is about 40 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These include Cramer, Jealousy, Maho Bay, Southgate, and Victory soils. All of these soils are on higher positions. In addition, Cramer, Maho Bay, and Southgate soils are shallow to bedrock. Jealously and Victory soils are moderately deep to bedrock.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Most areas of Parasol soils are used for pasture and rangeland. Many areas have been converted to urban uses.
DISTRIBUTION AND EXTENT: St. Croix Island, U.S. Virgin Islands. They are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina
SERIES ESTABLISHED: St. Croix, Island, U.S. Virgin Islands; 1932.
REMARKS: Diagnostic horizons and other features recognized in this pedon include:
Mollic epipedon - the zone from 0 to 13 inches (A1 and A2 horizons).
Argillic horizon - the zone from 13 to 24 inches (Bt horizons).
ADDITIONAL DATA: Characterization pedon - St. Croix Island, U.S. Virgin Islands; S64VI-10-3. Sample by NSSL, Lincoln NE., 9/1964.
MLRA: 271.
SIR: VI0015.