LOCATION CAYAGUA PREstablished Series
TAXONOMIC CLASS: Fine, mixed, semiactive, isohyperthermic Aeric Albaqualfs
TYPICAL PEDON: Cayagua sandy loam--pasture (Colors are for the moist soil).
Ap--0 to 4 inches; dark grayish brown (10YR 4/2) sandy loam; weak fine granular structure; very friable; nonsticky, nonplastic; many fine roots; strongly acid; abrupt smooth boundary (2 to 6 inches thick).
Bt1--4 to 10 inches; light brownish gray (10YR 6/2) clay; weak medium subangular blocky structure; very firm; slightly sticky, plastic; common fine roots; few faint clay films on ped surfaces and root channels; many coarse distinct strong brown (7.5YR 5/6) masses of iron accumulations; very strongly acid; clear wavy boundary (4 to 8 inches thick).
Bt2--10 to 20 inches; light brownish gray (10YR 6/2) clay; weak coarse angular blocky structure; firm; slightly sticky, plastic; few fine roots; common faint clay films on ped surfaces and root channels; many coarse distinct strong brown (7.5YR 5/6) and few fine distinct red (2.5YR 5/6) masses of iron accumulations; very strongly acid; clear wavy boundary (8 to 12 inches thick)
BC--20 to 27 inches; yellowish red (5YR 5/6) sandy loam; massive; friable, nonsticky, nonplastic; many medium prominent light gray (10YR 7/1) clay; massive; friable; nonsticky, plastic; few fine roots; very strongly acid; gradual wavy boundary (4 to 10 inches thick)
C1--27 to 36 inches; 60 percent yellowish red (5YR 4/6) sandy loam and 40 percent light gray (10YR 7/1) clay; massive; friable; nonsticky, nonplastic; quartz seams in the clayey sections; very strongly acid; gradual wavy boundary (6 to 12 inches thick)
C2--36 to 100 inches, 50 percent yellowish red (5YR 4/6) and 50 percent reddish yellow (7.5YR 6/6) sandy loam; massive; very friable; nonsticky, nonplastic; slightly acid.
TYPE LOCATION: Este SCD, Puerto Rico; approximately 3.0 miles northwest of the town of Humacao, about 450 feet west of Kilometer Marker 0.7 on P.R. Highway No. 953 (75 feet west of fence).
RANGE IN CHARACTERISTICS: Thickness of the solum ranges from 18 to 36 inches. Reaction is very strongly acid or strongly acid in the A and Bt horizons, and from moderately acid to neutral in the BC and C horizons.
The A or Ap horizon has hue of 10YR or 2.5Y, value of 3 and 4, chroma of 2 to 4. Texture is sandy loam, sandy clay loam, or clay loam.
The Bt horizon has hue of 10YR or 2.5Y, value of 4 to 7, chroma of 2 or less. Redoximorphic features in shades of brown, yellow, gray, and red range from few to many. Texture is sandy clay or clay.
The BC horizon has hue of 5YR or 7.5YR, value of 4 to 6, and chroma of 4 to 8. Redoximorphic features in shades of gray and brown range from few to many. Texture ranges from sandy loam to sandy clay loam.
The C horizon has hue of 5YR or 7.5YR, value of 4 to 6, and chroma of 4 to 8. Redoximorphic features in shades of gray and brown range from few to many. Texture ranges from sandy loam to sandy clay loam.
COMPETING SERIES: There are no known series in the same family.
GEOGRAPHIC SETTING: Cayagua soils are on foot slopes and side slopes. Slopes range from 2 to 20 percent. They formed in regolith that consists of residuum which derived from coarse-textured plutonic rocks. The climate is humid tropical. The average annual precipitation ranges from 80 to 90 inches. The average annual temperature ranges from 76 to 78 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the Candelero, Ingenio, Limones, Mayo, and Pandura series. Candelero soils are on lower alluvial fan positions and have less clay in the subsoil. Ingenio and Limones soils are on higher side slopes and hill top positions and have kaolinitic control sections. In addition, Ingenio soils are well drained and are Ultisols while Limones soils are moderately well drained and are Oxisols. The well to excessively drained Mayo soils are on lower foot slopes and alluvial fan positions below Cayagua soils and have less developed subsoils. The well drained Pandura soils are on higher side slope positions and are shallow over plutonic bedrock.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow permeability.
USE AND VEGETATION: Most areas of Cayagua soils are used for the production of sugarcane. Many areas have been planted to Pangola and other adapted grasses and used as pasture. The vegetation is mostly native grasses and shrubs.
DISTRIBUTION AND EXTENT: Humid plutonic uplands 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; 1936.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Ochric epipedon - the zone from 0 to 4 inches (Ap horizon).
Argillic horizon - the zone from 4 to 20 inches (Bt horizon).
This soil is in MLRA 270.