LOCATION MARAGUEZ           PR
Established Series
Rev. REG: LHR
08/2000

MARAGUEZ SERIES


The Maraguez series is well drained, moderately permeable soils formed in loamy materials weathered from volcanic rocks. They are steep and very steep soils on side slopes and ridges of the humid uplands. These soils are silty clay loam slightly acid in the A horizon; clay loam slightly acid in the cambic horizon and loam or silt loam in the C horizon.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, isohyperthermic Typic Eutrudepts

TYPICAL PEDON: Maraguez silty clay loam - shade grown coffee.
(Colors are for moist soils.)

Ap--0 to 6 inches; dark brown (10YR 3/3) silty clay loam; moderate fine and medium granular structure; firm, slightly sticky, slightly plastic; many fine and medium roots; few wormholes; fine and medium gravel 5 percent from 1/2 to 1 inch in diameter; slightly acid; clear wavy boundary. (5 to 7 inches thick)

B2--6 to 12 inches; brown (10YR 4/3) 60 percent and dark brown (10YR 3/3) 40 percent, clay loam; weak fine and medium subangular blocky structure; firm, slightly sticky, slightly plastic; few fine and medium roots; few wormholes; fine volcanic fragments 5 to 10 percent from 1/2 to 1 inch in diameter; slightly acid; clear wavy boundary. (4 to 7 inches thick)

B3--12 to 21 inches; dark yellowish brown (10YR 4/4) loam; weak fine subangular blocky structure; friable, slightly sticky, slightly plastic; few fine and medium roots; fine subangular volcanic fragments 5 to 10 percent from 1/2 to 1 inch in diameter; common fine quartz grains; slightly acid; clear wavy boundary. (7 to 10 inches thick)

C--21 to 60 inches; yellowish brown (10YR 5/4) loam; massive; friable, slightly sticky, slightly plastic; few fine and medium roots; fine and medium volcanic fragments 5 to 10 percent from 1/2 to 1 inch in diameter; many fine quartz grains; medium acid.

TYPE LOCATION: Sur SCD, Puerto Rico, 50 feet east of kilometer marker 16.1 on Highway 139.

RANGE IN CHARACTERISTICS: Thickness of the solum ranges from 16 to 24 inches. Depth to the semi-consolidated volcanic rock is over 60 inches. Consistence is slightly sticky and slightly plastic in the whole profile. Reaction is medium or slightly acid. Fine rock fragments range from 2 to 10 percent throughout. Organic carbon decreases regularly with depth. The mean annual soil temperature is 76 degrees F.

The A horizon has hue of 10YR, values of 3 or 4, and chroma of 2 and 3. Texture is silty clay loam. Structure is weak or moderate, fine or medium granular.

The B2 horizons have matrix colors in hues of 10YR, values or 4 or 5, and chroma of 3 and 4. Texture of the B2 horizon is clay loam, silty clay loam, or loam. Texture of the B3 horizon is loam or silt loam. Structure of the B horizons is weak fine or medium subangular blocky.

The C horizon is loam or silt loam.

COMPETING SERIES: This is the Morado series in the same family. The Caguabo, Juncos, Junquitos, Mabi, Malaya, Maresua, Montegrande, Mucara, Pandura, Plata and Quebrada series are similar soils in related families. The Marado soils are pinkish and are shallower to the semi-consolidated rock. The Caguabo and Malaya soils are shallower to the volcanic rock. The Juncos, Mabi, Montegrande and Mucara soils all have finer textured and have higher COLE values. The Junquitos soils have finer texture and low chroma mottles. The Maresua soils have finer texture and are gravelly throughout. The Pandura are coarser textured and shallow to the weathered rock. The Plata soils have more than 35 percent by volume of gravel. The Quebrada soils are finer texture throughout.

GEOGRAPHIC SETTING: The Maraguez soils are steep and very steep soils on side slopes and ridges of strongly dissected volcanic uplands with slope gradients of 20 to 60 percent. The soil formed in moderately medium textured residuum weathered from basic volcanic rocks. The climate is humid tropical. The average annual precipitation ranges from 60 to 70 inches and the mean annual temperature ranges from 76 to 78 degrees F.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Morado, Mucara, Quebrada, and Caguabo soils. The Caguabo soils are underlain by hard rock at 20 inches or less.

DRAINAGE AND PERMEABILITY: Well drained; very rapid runoff; moderate permeability.

USE AND VEGETATION: Most of the acreage is in native pasture and shade grown coffee.

DISTRIBUTION AND EXTENT: Humid uplands of Puerto Rico. The series is of minor extent with about 13,000 acres.

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

SERIES ESTABLISHED: Ponce Survey Area, Puerto Rico; 1971.


National Cooperative Soil Survey
U. S. A.