LOCATION CUYON PREstablished Series
TAXONOMIC CLASS: Sandy-skeletal, mixed, isohyperthermic Torrifluventic Haplustolls
TYPICAL PEDON: Cuyon loam - guineagrass. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 11 inches; dark brown (10YR 3/3) loam; weak fine granular structure; friable, slightly sticky, slightly plastic; many fine roots; few rounded rock fragments; 1 to 2 inches (25 to 50 cm) in diameter; neutral, clear irregular boundary. (8 to 12 inches thick)
C1--11 to 17 inches; consists of 70 percent medium and coarse gravel, 25 percent coarse sand, and 5 percent silt by volume. (5 to 10 inches thick)
C2--17 to 24 inches; consists of dark brown (10YR 3/3) gravelly coarse sand with less than 10 percent silt.
TYPE LOCATION: Caribe SCD, Puerto Rico, 40 meters east of kilometer marker 39.05 of Highway No. 14.
RANGE IN CHARACTERISTICS: Thickness of A horizon and depth to the coarse materials range from 8 to 12 inches (20-30 cm). The A horizons are very dark grayish brown, (10YR 3/2) or dark brown (10YR 3/3). Loam is the dominant type. Structure is weak fine or moderate medium granular.
The C horizons have varying amounts of sand and gravel and less than 10 percent silt. These soils are neutral or mildly alkaline. The percent of gravel ranges from 50 to 80 percent.
COMPETING SERIES: These are the Jacaguas, Mokuleia, Reilly, San Anton, and San German series. The Jacaguas soils have more clay in the control section and have cambic horizons. The Mokuleia soils lack the gravel and have carbonatic mineralogy. The Reilly soils are acid and occur in the more humid areas. The San Anton soils are moderately fine textures. The San German soils are calcareous and are underlain by hard limestone at depths of 20 inches or less.
GEOGRAPHIC SETTING: The Cuyon soils occur very close to the river banks on nearly level to gently sloping terrain with slope gradients of 0 to 5 percent. The soil formed in stratified coarse textures sediments of mixed origin. The climate is semiarid. The mean annual precipitation ranges for 25 to 45 inches and the mean annual temperature is 78 to 80 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing Jacaguas and San Anton soils and the Constancia, Cortada, and Machuelo soils, all of which occur in flood plains. The Constancia and Machuelo soils are wetter and have low chroma mottles. Cortada soils have B horizons and have thicker profiles.
DRAINAGE AND PERMEABILITY: Excessively drained; slow runoff; rapid permeability.
USE AND VEGETATION: Mostly in native pastures, guinea and pajon grasses.
DISTRIBUTION AND EXTENT: Semiarid flood plains of Puerto Rico. The series is of minor extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina
SERIES ESTABLISHED: Ponce Survey Area, Puerto Rico; l971.
REMARKS: The Cuyon soils were formerly classified in the Alluvial great soil group.