LOCATION CAGUABO PREstablished Series
TAXONOMIC CLASS: Loamy, mixed, active, isohyperthermic, shallow Typic Eutrudepts
TYPICAL PEDON: Caguabo clay loam - native pasture and weeds. (Colors are for moist conditions.)
Ap--0 to 4 inches; dark grayish brown (10YR 4/2) clay loam; weak fine granular structure; friable, slightly sticky, slightly plastic; about 10 percent, by volume, igneous rock fragments; common fine roots; slightly acid; clear smooth boundary. (2 to 5 inches thick)
Bw--4 to 10 inches; brown (10YR 4/3) very gravelly clay loam; weak fine subangular blocky structure parting to weak fine granular; friable, slightly sticky, slightly plastic; about 60 percent, by volume, igneous rock fragments; few fine roots; slightly acid; clear smooth boundary. (4 to 8 inches thick)
Cr--10 to 16 inches; mixture of weathered and partially weathered basalt rock fragments and saprolite that can be penetrated with the spade; slightly acid. (0 to 7 inches thick)
R--16+ inches; consolidated basalt rock.
TYPE LOCATION: Oeste SCD, Puerto Rico. Approximately 1.5 miles northwest of the town of Anasco; about 300 feet north of intersection of Highways 2 and 110.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 6 to 20 inches and depth to bedrock ranges from 10 to 20 inches. Content of pebbles range from 2 to 20 percent, by volume and cobbles from 0 to 5 percent, by volume in the A or Ap horizon and from 2 to 70 percent, by volume, pebbles or occasionally from 20 to 75 percent, by volume, paragravels in the Bw and BC horizons Reaction is moderately acid to slightly acid throughout.
The A or Ap horizon has hue of 7.5YR to 2.5Y, value of 3 to 5, and chroma of 2 to 6. Texture is loam, clay loam, or their gravelly analogs.
The Bw horizon has hue of 7.5YR to 2.5Y, value of 2 to 6, and chroma of 3 to 6. Texture is gravelly to extremely analogs of silty clay loam, clay loam, or clay. Content of saprolite ranges from 0 to 20 percent, by volume.
The BC horizon, where present, has hue of 2.5Y, value of 5, and chroma of 4. Texture is gravelly to extremely analogs of silty clay loam.
The C horizon, where present, has hue of 7.5YR to 2.5Y, value of 2 to 6, and chroma of 3 to 6; or it has no dominant matrix color and is multicolored. Texture is gravelly or very gravelly analogs of sandy clay loam or clay loam. Content of saprolite ranges from 20 to 60 percent, by volume.
The Cr horizon is composed of weathered basalt saprolite that is similar in color and texture as the C horizon.
The R layer is consolidated basalt bedrock.
COMPETING SERIES: There are no other known series in the same family.
GEOGRAPHIC SETTING: Caguabo soils are on lower positions of strongly dissected volcanic uplands at elevations below 1,800 feet or 550 meters. Slope range from 12 to 60 percent. They formed in fine-textured residuum or partially weathered basalt. The climate is humid tropical. The average annual precipitation ranges from 75 to 85 inches and the average annual temperature ranges from 75 to 77 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the Juncos, Mabi, Maraquez, Maresua, Morado, Mucara, and Quebrada soils. All of these soils are deeper to bedrock. In addition, the Juncos, Mabi, and Mucara soils are have clayey, smectitic control sections. The Maraguez and Morado soils and have fine-loamy, mixed control sections. Maresua soils have mixed clayey-skeletal control sections. Quebrada soils have mixed clayey control sections.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Most areas of this soil are used for pasture. A few small areas are planted to woodland. Vegetation consists of native and introduced grasses, shrubs, and trees.
DISTRIBUTION AND EXTENT: Humid uplands of Puerto Rico. The series is of large extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina.
SERIES ESTABLISHED: Humacao Survey Area, Puerto Rico; 1969.
REMARKS: These soils were formerly included in the Mucara series.
Diagnostic horizons and features recognized in this pedon:
Ochric epipedon - the zone from 0 to 4 inches (Ap horizon).
Cambic horizon - the zone from 4 to 10 inches (Bw horizon).
Lithic contact - hard bedrock at 16 inches (R layer).
Caguabo soils are in MLRA 270.