LOCATION GLYNN VIEstablished Series
TAXONOMIC CLASS: Clayey-skeletal, mixed, superactive, isohyperthermic Typic Argiustolls
TYPICAL PEDON: Glynn gravelly loam (Colors for moist conditions.)
A1--0 to 4 inches; dark brown (10YR 3/3) gravelly loam, moderate medium and coarse granular structure; friable; many fine and medium roots, few coarse roots; many fine to coarse wormcasts and insectcasts; about 30 percent, by volume, pebbles; neutral; clear wavy boundary.
A2--4 to 10 inches; dark brown (10YR 3/3) gravelly clay loam; moderate medium and coarse granular structure; friable, sticky, plastic; many fine and medium roots, few coarse roots; many fine to coarse wormcasts; many fine and medium insectcasts; about 30 percent, by volume, pebbles; few fine and medium faint yellowish brown (10YR 5/6) masses of iron accumulation; neutral; abrupt smooth boundary. (Combined thickness of the A horizon is 10 to 20 inches)
Bt--10 to 17 inches; dark yellowish brown (10YR 4/4) very gravelly clay; strong medium prismatic structure; slightly hard, firm, very sticky, very plastic; common fine and medium roots, few coarse roots; common fine, medium and coarse wormcasts; common medium insectcasts; few faint clay films on faces of peds; about 35 percent, by volume, pebbles; few fine and medium faint yellowish brown (10YR 5/6) masses of iron accumulation; slightly alkaline; gradual wavy boundary. (0 to 10 inches thick)
BC--17 to 27 inches; yellowish brown (10YR 5/4) very gravelly clay loam; weak fine and medium prismatic structure; firm, very sticky, very plastic; few fine and medium roots; common fine and medium wormcasts; common fine insectcasts; few faint clay films on faces of some peds; about 35 percent, by volume, pebbles; many fine and medium iron-manganese concretions; common fine distinct strong brown (7.5YR 5/6) and few fine faint yellowish brown (10YR 5/6) masses of iron accumulation; moderately alkaline; gradual wavy boundary. (2 to 20 inches thick)
C--27 to 32 inches; yellowish brown (10YR 5/4) very gravelly sandy clay loam; massive; friable, slightly sticky, slightly plastic; few medium roots; common fine and medium wormcasts; common fine medium insectcasts; about 35 percent, by volume, pebbles; few fine distinct strong brown (7.5YR 5/6) and few fine faint yellowish brown (10YR 5/6) masses of iron accumulation; strongly alkaline; clear wavy boundary. (2 to 20 inches thick)
2C--32 to 41 inches; light olive brown (2.5Y 5/4) very gravelly clay; massive; firm, very sticky, very plastic; few fine and medium roots; common pressure faces on vertical and horizontal faces of peds; many medium and coarse soft masses of calcium carbonate; common fine and medium wormcasts; about 50 percent, by volume, pebbles; many fine and medium iron-manganese concretions; common fine and medium light yellowish brown (2.5Y 6/4) and few fine distinct brownish yellow (10YR 6/8) masses of iron accumulation; few medium distinct very pale brown (10YR 8/3) iron depletions; strongly alkaline; gradual wavy boundary. (0 to 20 inches thick)
3C--41 to 60 inches; light olive brown (2.5Y 5/4) very gravelly sandy clay loam; massive; friable, slightly sticky, slightly plastic; few fine and medium roots; many medium and coarse soft masses of calcium carbonate; common fine and medium wormcasts; about 40 percent, by volume, pebbles; many fine and medium iron-manganese concretions; few fine distinct brownish yellow (10YR 6/8) masses of iron accumulation; common medium distinct pale brown (10YR 8/3) iron depletions; strongly alkaline.
TYPE LOCATION: St. Croix Island, U.S. Virgin Islands. Approximately 0.3 mile south of Petronella on VI-62, about 200 feet east of VI-62 in a pasture. East Point topographic quadrangle; lat. 17 degrees 43 minutes 30 seconds N., long. 64 degrees 39 minutes 57 seconds W.; PRD 1940.
RANGE IN CHARACTERISTICS: The solum thickness ranges from 20 to 60 inches or more. Reaction ranges from neutral to strongly alkaline throughout the profile.
The A horizon has hue of 5YR to 2.5Y, value of 2 or 3 and chroma of 2 or 3. Texture is loam or clay loam in the fine-earth fraction. Content of pebbles and cobbles ranges from 5 to 60 percent by volume.
The Bt horizon has hue of 5YR to 5Y, value of 3 to 7, and chroma of 3 to 6. Masses of iron accumulations in shades of brown and yellow range from none to few. Texture is clay loam or clay in the fine-earth fraction. Content of pebbles and cobbles ranges from 35 to 60 percent by volume.
The BC horizon, where present, has hue of 5YR to 2.5Y, value of 3 to 7, and chroma of 3 to 6. Masses of iron accumulations in shades of brown and yellow ranged from none to common. Texture is clay loam or clay in the fine-earth fraction. Content of pebbles and cobbles ranges from 35 to 60 percent by volume.
The C horizon has hue of 5YR to 2.5Y, value of 4 to 8, and chroma of 2 to 8. Redoximorphic features in shades of brown and yellow range from few to common. Texture is sandy clay loam, clay loam, or clay in the fine-earth fraction. Content of pebbles and cobbles ranges from 35 to 60 percent by volume. Soft masses of calcium carbonate range from few to many.
COMPETING SERIES: There are no competing series in the same family.
GEOGRAPHIC SETTING: Glynn soils are on alluvial fans and terraces adjacent to volcanic hills and mountains. They formed in alluvial sediments weathered from volcanic residuum. The slopes range from 0 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 the Arawak, Carib, Hesselberg, Lameshur, Sandy Point, Sion, Solitude, and Sugar Beach soils. Arawak soils are on higher positions and are shallow to weathered limestone. Carib, Hesselberg, Sandy Point, Sion, Solitude, and Sugar Beach soils have less than 35 percent rock fragments in the particle-size control section. In addition, Carib soils are in flood plains, have fine-loamy particle-size control sections, and are somewhat poorly drained. Hesselberg soils are on marine terraces and are shallow to a root restrictive petrocalcic horizon. Sandy Point and Sugar Beach soils are in saline marshes and flats and are very poorly drained. Sion soils are on higher side slopes and valley floors. Solitude soils are on lower positions and are somewhat poorly drained. Lameshur soils are on similar positions but have loamy-skeletal particle-size control sections.
DRAINAGE AND PERMEABILITY: Well drained; moderately slowly permeability.
USE AND VEGETATION: Most areas are used for pasture. Some areas are being converted to urban land.
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 features recognized in this pedon include:
Mollic epipedon - the zone from 0 to 10 inches (A1 and A2 horizons).
Argillic horizon - zone from 10 to 27 inches (Bt horizon).
Skeletal feature - more than 35 percent weighted average rock fragments in the particle-size control section.
ADDITIONAL DATA: Characterization pedon - St. Croix Island, U.S. Virgin Islands; S92VI-10-10. Sample by NSSL, Lincoln, NE., 1991.
MLRA: 271, 273.
SIR: VI0008.