LOCATION HUMACAO PREstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, isohyperthermic Typic Hapludolls
TYPICAL PEDON: Humacao loam - sugar cane
(Colors are for the moist soil)
Ap--0 to 14 inches, dark brown (7.5YR 3/2) loam, few medium distinct brown (10YR 4/3) mottles; weak fine and medium granular structure; friable, nonsticky, slightly plastic; many fine roots; 2 percent fine subrounded rock fragments; many fine quartz crystals; few fine dark minerals; medium acid; clear smooth boundary. (8 to 18 inches thick)
B2--14 to 18 inches; brown (10YR 4/3) sandy clay loam, tongues of dark brown (7.5YR 3/2); weak fine subangular blocky structure; friable, nonsticky, slightly plastic; few fine roots; 5 percent fine subrounded rock fragments; common fine quartz crystals; common fine dark minerals; medium acid; clear smooth boundary. (4 to 10 inches thick)
C1--18 to 31 inches; yellowish brown (10YR 5/4) clay loam, common medium faint dark yellowish brown (10YR 4/4) mottles; massive; firm, slightly sticky, slightly plastic; few fine roots; common fine quartz crystals; 5 percent fine subrounded partially weathered rock fragments; few fine dark concretions; medium acid; clear smooth boundary. (8 to 16 inches thick)
C2--31 to 60 inches; yellowish brown (10YR 5/6) clay loam, many medium prominent dark brown (10YR 3/3) and common medium distinct yellowish red (5YR 5/8) mottles; massive; friable, slightly sticky, slightly plastic; few fine quartz crystals; 5 percent fine partially weathered rock fragments; common medium dark concretions; slight acid.
TYPE LOCATION: Este SCD, Puerto Rico; 0.1 mile south of kilometer marker 1.2 or Highway 908, 10 feet west of farm road.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 12 to 28 inches. Mean annual soil temperature ranges from 76 to 80 degrees F. Coarse fragment content ranges from 0 to 10 percent throughout. The soils are medium acid or slightly acid throughout. Base saturation of the soil ranges from 50 to 80 percent.
The A horizons have hues of 7.5YR or 10YR, values of 2 or 3, and chroma of 2 or 3. They are loam.
The B horizons have hues of 5YR to 7.5YR, values of 4 to 6, and chroma of 3 to 8. They are sandy clay loam, heavy loam or clay loam. They have weak fine to medium subangular blocky structure.
The C horizons have hues of 5YR to 7.5YR, values of 4 to 6, and chroma of 4 to 8. They are sandy clay loam, heavy loam or clay loam. They are massive.
COMPETING SERIES: There are no other known series in the same family.
The Dique, Estacion, Maraquez, Morado, Parasol, and Toa series are similar soils in related families. Dique, Maraquez, and Morado soils have ochric epipedons. Estacion and Toa soils have and argillic horizon and ustic moisture regimes.
GEOGRAPHIC SETTING: The Humacao soils are gently sloping on terraces above the river flood plains with slope gradients of 2 to 5 percent. The soils formed in medium and moderately fine textured sediments derived form soils of plutonic parent materials. The climate is humid tropical. The average annual rainfall ranges from 85 to 90 inches and the mean annual temperature from 77 to 80 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Candelero, Coloso, Ingenio, Jaqueyes, Limones, Maunabo, and Vivi soils. Candelero soils are somewhat poorly drained. Coloso, Maunabo, and Vivi soils are on river flood plains. Ingenio, Jaqueyes, and Limones soils are on sideslopes of the uplands at higher elevations.
DRAINAGE AND PERMEABILITY: Humacao soils are well drained and have medium runoff and moderate permeability.
USE AND VEGETATION: Major uses are for growing sugar cane and pasture. Native vegetation consists of grasses and brush.
DISTRIBUTION AND EXTENT: Humid plutonic areas of Puerto Rico. The series is of small extent with about 1,000 acres.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina
SERIES ESTABLISHED: Soil Survey of Puerto Rico, l942.