LOCATION CHIQUITO PREstablished Series
TAXONOMIC CLASS: Clayey-skeletal, mixed, active, isothermic Lithic Eutrudepts
TYPICAL PEDON: Chiquito gravelly clay loam--coffee plantation (Colors are for moist soil).
Ap--0 to 5 inches; dark grayish brown (10YR 4/2) gravelly clay loam, gray (10YR 5/1) dry; strong very fine and fine granular structure; hard, firm; slightly sticky, moderately plastic; many very fine and fine roots; many fine and medium interstitial pores; about 18 percent, by volume, pebbles and about 2 percent, by volume, parapebbles; neutral; gradual wavy boundary. (5 to 7 inches thick)
Bw1--5 to 11 inches; brown (10YR 4/3) very gravelly clay loam, dark grayish brown (10YR 4/2) dry; moderate very fine and fine subangular blocky structure; hard, firm; slightly sticky, moderately plastic; many very fine and fine roots; common fine and medium irregular pores and few fine and medium interstitial pores; about 35 percent, by volume, pebbles and about 5 percent, by volume, parapebbles; neutral; clear wavy boundary.
Bw2--11 to 18 inches; very dark grayish brown (10YR 3/2) extremely gravelly clay loam, dark gray (10YR 4/1) dry; weak very fine and fine subangular blocky structure; slightly hard, friable; slightly sticky, moderately plastic; many very fine and fine roots; common fine and medium interstitial pores and few fine and medium irregular pores; about 50 percent, by volume, pebbles and about 10 percent, by volume, parapebbles; neutral; abrupt wavy boundary. (Combined thickness of the Bw horizons ranges from 8 to 13 inches.)
R--18+ inches; hard fractured consolidated mudstone.
TYPE LOCATION: Yauco, Puerto Rico. Approximately 4.1 miles southwest from the Castaner community from the intersection of P.R. Hwy. 135 and P.R. Hwy. 374; about 0.4 mile southwest of Hacienda Las Pinas homestead on coffee plantation; USGS Monte Guilarte topographic quadrangle (1960); lat. 18 degrees 07 minutes 50.5 seconds N. and long. 66 degrees 52 minutes 04 seconds W.
RANGE IN CHARACTERISTICS: Depth to hard fractured consolidated volcanic bedrock ranges from 14 to 19 inches. Reaction ranges from slightly acid to neutral throughout, except where the surface has been limed. The combined total of rock fragments in the control section is more than 35 percent by volume.
The A or Ap horizon has hue of 10YR or 2.5Y, value of 3 to 5, and chroma of 1 to 4. Content of rock fragments range from 5 to 25 percent, by volume. Texture is clay loam in the fine-earth fraction.
The Bw horizon has hue of 10YR or 2.5Y, value of 3 to 6, and chroma of 1 to 3. Content of rock fragments range from 35 to 70 percent, by volume. Texture is clay loam in the fine-earth fraction.
The R layer is composed of hard fractured consolidated mudstone.
COMPETING SERIES: These are no known series in the same family.
GEOGRAPHIC SETTING: Chiquito soils are on side slopes and summits of mountains on the Humid Mountains and Valleys MLRA. Slopes range from 40 to 90 percent. They formed in residuum material weathered from mudstone. The climate is humid tropical. The average annual precipitation ranges from 68 to 134 inches and the average annual temperature ranges from 62 to 68 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Agueybana (T), Cuchillas, Maricao and Rubias (T) series. Agueybana (T) and Maricao soils have an argillic horizon and have finer textured profiles. Cuchillas and Rubias (T) soils are moderately deep to bedrock. Chiquito soil is in a perudic soil moisture regime. Chiquito soils formed in the Yauco Mudstone Formation (Ky).
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Most areas of Chiquito soils are on naturalized pastureland, bananas, citrus, coffee and plantains. The vegetation consists of native and indroduced grasses, shrubs and trees.
DISTRIBUTION AND EXTENT: Side slopes and summits of mountains of southern Puerto Rico. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina.
SERIES ESTABLISHED: Yauco Municipality, Puerto Rico; 2007. The name is from Chiquito River, nearby it was originally recognized.
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 6 to 18 inches (Bw1 and Bw2 horizons).
Lithic contact - the contact at 18 inches (R layer).
Chiquito soils were formerly included in the Caguabo series. A soil moisture and soil temperature study performed in the San German Area Soil Survey Update recognized the Perudic Soil Moisture Regime in Puerto Rico, recognized the isothermic soil temperature regime at 750 meters above sea level (in Perudic Soil Moisture Regime) and 900 meters above sea level (in Udic Soil Moisture Regime) and adjusted the isothermic-isohyperthermic line.
Chiquito soils are in MLRA 270.