LOCATION CALLABO PREstablished Series
TAXONOMIC CLASS: Clayey, mixed, superactive, isohyperthermic, shallow Typic Dystrustepts
TYPICAL PEDON: Callabo silty clay loam--guineagrass (Colors are for moist soil unless otherwise stated).
Ap--0 to 5 inches; very dark grayish brown (10YR 3/2) silty clay loam; moderate medium granular structure; friable; slightly sticky, slightly plastic; many fine roots; about 10 percent, by volume, angular volcanic fragments; few wormholes; slightly acid; clear smooth boundary. (4 to 5 inches thick)
Bw1--5 to 13 inches; brown (10YR 4/3) silty clay loam; weak medium and coarse subangular blocky structure; firm; slightly sticky, slightly plastic; common fine roots; about 10 percent, by volume, angular volcanic fragments; few wormholes; many medium distinct very dark grayish brown (10YR 3/2) areas of Ap material; neutral; clear wavy boundary.
Bw2--13 to 19 inches; dark yellowish brown (10YR 4/4) clay loam; weak coarse subangular blocky structure; friable; slightly sticky, slightly plastic; few fine roots; about 15 percent, by volume, angular volcanic fragments; neutral; clear wavy boundary. (Combined thickness of the Bw horizons range from 10 to 18 inches)
C--19 to 27 inches; highly weathered volcanic rock; few stringers and tonguing of Bw horizon material; neutral; clear wavy boundary. (6 to 12 inches thick)
R--27 to 40 inches; hard, semiconsolidated volcanic rock.
TYPE LOCATION: Caribe SCD, Puerto Rico; approximately 100 meters west of kilometer marker 2.3 of P.R. Highway 512.
RANGE IN CHARACTERISTICS: Thickness of the solum ranges from 14 to 24 inches. Depth to the semiconsolidated rock ranges from 20 to 40 inches. Reaction is slightly acid or neutral throughout.
The A or Ap horizon has hue of 10YR, value of 3 or 4, and chroma of 2 to 4. Texture is silty clay loam.
The Bw horizon has hue of 10YR, value of 4 or 5, and chroma of 3 or 4. In some pedons, there is some mixing of Ap material in the upper part. Texture is clay loam or silty clay loam.
The C horizon consists of highly weathered and partially weathered volcanic rock. In some pedons, there is tonguing of Bw material.
The R horizon consists of hard consolidated volcanic rock that is rippable by heavy machinery.
COMPETING SERIES: There are no known series in the same family.
GEOGRAPHIC SETTING: Callabo soils are on side slopes of strongly dissected uplands. Slopes range from 12 to 60 percent. They formed in moderately fine-textured residuum that weathered from basic volcanic rocks. The climate is semiarid tropical. The average annual rainfall ranges from 30 to 50 inches and the average annual temperature is 75 to 80 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the Jacana, Juana Diaz, and Llanos soils. Jacana soils are on lower positions, are Mollisols, and have cracks when dry. Juana Diaz soils are on similar positions, have less clay in the subsoil, and are shallow to weathered sandstone. Llanos soils are on lower terrace positions, are very deep, and are Vertisols.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Most areas of Callabo soils are used as pasture. A few acres are cultivated. The vegetation consists of native and introduced grasses.
DISTRIBUTION AND EXTENT: Semiarid sections of Puerto Rico. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina.
SERIES ESTABLISHED: Ponce Survey Area, Puerto Rico, 1971.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Ochric epipedon - the zone from 0 to 5 inches (Ap horizon).
Cambic horizon - the zone from 5 to 19 inches (Bw1 and Bw2 horizons).
Moderately deep feature - Consolidated bed rock at 27 inches (R horizon).
These soils were formerly included in the Descalabrado series.