LOCATION FORTUNA            PR
Established Series
Rev. LHR
06/2002

FORTUNA SERIES


The Fortuna series consists of plastic, clayey soils with olive gray A horizons and greenish gray, mottled B and C horizons.

TAXONOMIC CLASS: Fine, mixed, active, acid, isohyperthermic Fluvaquentic Endoaquepts

TYPICAL PEDON: Fortuna clay - sugarcane field. (Colors are for moist soil.)

Ap--0 to 5 inches; olive gray (5Y 4/2) clay; few fine faint greenish gray and few fine prominent strong brown mottles; massive; very firm, slightly sticky, slightly plastic; common fine roots; strongly acid; abrupt smooth boundary. (4 to 9 inches thick)

B2lg-- 5 to 9 inches; dark greenish gray (5GY 4/1) clay; common medium prominent strong brown (7.5YR 5/8) mottles; massive; very firm, slightly sticky, plastic; common fine roots; few fine rock fragments; strongly acid; abrupt smooth boundary. (3 to 8 inches thick)

B22g--9 to 18 inches; greenish gray (5GY 5/1) clay; many medium prominent yellowish brown (10YR 5/8) mottles; weak coarse subangular blocky structure; very firm, slightly sticky, plastic; common fine roots; few fine black concretions; strongly acid; gradual smooth boundary. ( 7 to 12 inches thick)

B3g--18 to 30 inches; greenish gray (5GY 5/1) clay; common medium prominent yellowish brown (10YR 5/8) mottles; weak coarse subangular blocky structure; very firm, slightly sticky, plastic; few fine roots; dark coatings in root channels; strongly acid; gradual smooth boundary. (8 to 16 inches thick)

Cg--30 to 77 inches plus; greenish gray (5GY 5/1) clay; many coarse prominent yellowish brown (10YR 5/8) mottles; massive, very firm, sticky, plastic; very strongly acid.

TYPE LOCATION: Este SCD, Puerto Rico; 2.0 kilometers south Naguabo, 10 kilometers northeast of Humacao, 2.1 kilometers north of bridge on Anton Ruiz river on Highway 3, near abandoned railroad.

RANGE IN CHARACTERISTICS: Solum thickness ranges from 22 to 45 inches. The reaction of all horizons is strongly or very strongly acid.

Color of the A horizon is dark grayish brown (10YR 4/2; 2.5Y 4/2) through olive brown (2.5Y 4/4); dark yellowish brown (10YR 4/4) or olive gray (5Y 4/2) through olive (5Y 4/4). Texture is clay or silty clay. Structure is weak subangular blocky, weak granular or massive. The B horizon has colors of dark grayish brown (2.5Y 4/2) through light brownish gray (2.5Y 6/2) or dark gray (2.5Y 4/; 5Y 4/1), gray (5/ , N6/ ; 5Y 5/1, 6/1) or dark greenish gray (5GY, 5G, 5BG 4/1) through greenish gray (5GY, 5G, 5GB, 6/1). Mottles are common or many and chromas range from 1 through 8. Texture is silty clay or clay. The structure is weak subangular blocky or massive. Black concretions are few or common.

The C horizon has dominant colors with hues of 5Y, and 5GY through 5BG; values of 4 through 7; and chromas of 2 or less. Mottles are common or many and chromas are 1 through 8. Texture is clay or silty clay.

COMPETING SERIES: These are the Bajura, Coloso, Corcega, Igualdad, Maunabo, Perchas, Pinones, Reparada, Santoni, Talante, and Vayas soils. The Bajura, Igualdad, and Vayas soils have control sections with pH values of 5.5 or more. The Coloso, Corcega and Talante soils have subhorizons with dominant colors with chromas of 3 or more within 30 inches of the surface. The Maunabo and Perchas soils have organic matter content that decreases regularly with depth. The Pinones and Reparada soils have organic layers within 30 inches of the soil surface. The Santoni soils are calcareous.

GEOGRAPHIC SETTING: The Fortuna soils occur on nearly level flood plains with slope gradients of 0 to 2 percent. The regolith is clayey sediments of mixed origin. The climate is humid tropical. The average annual precipitation is 80 inches and the mean annual temperature is 78 degrees F.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Bajura, Caloso, and Maunabo soils and the Toa, Dique, and Reilly soils. Dique soils have fine-loamy control sections. Reilly soils have sandy-skeletal control sections. Toa soils have mollic epipedons and are not dominanted by gray colors.

DRAINAGE AND PERMEABILITY: Poorly drained. Runoff is slow. Permeability is slow.

USE AND VEGETATION: Most areas are used for growing sugarcane.

DISTRIBUTION AND EXTENT: Humid river flood plains of Puerto Rico. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina

SERIES ESTABLISHED: Soil Survey of Puerto Rico; 1942.

REMARKS: These soils were formerly classified in the Alluvial great soil group.


National Cooperative Soil Survey
U.S.A.