LOCATION NIPE PREstablished Series
TAXONOMIC CLASS: Very-fine, ferruginous, isohyperthermic Typic Acrudox
TYPICAL PEDON: Nipe clay--forestland (Colors are for moist soil).
Oi--0 to 2 inches; undecomposed plant material; abrupt smooth boundary. (0 to 3 inches thick)
Ap--2 to 7 inches; dusky red (10R 3/3) clay; strong fine granular structure; hard, firm; slightly sticky, slightly plastic; common fine roots, few medium and coarse roots; few fine irregular pores and common fine vesicular pores; about 3 percent, by volume, iron-manganese concretions; strongly acid; clear smooth boundary. (5 to 13 inches thick)
A--7 to 11 inches; dusky red (10R 3/3) clay; strong fine granular structure; hard, firm; slightly sticky, slightly plastic; common fine roots; few fine irregular pores; about 6 percent, by volume, iron-manganese concretions; moderately acid; clear smooth boundary. (0 to 11 inches thick)
Bo1--11 to 22 inches; dusky red (10R 3/4) clay; moderate medium subangular blocky structure; slightly hard, firm; slightly sticky, slightly plastic; few faint clay films on ped faces; few fine roots; few fine tubular and irregular pores; about 2 percent, by volume, iron-manganese concretions; moderately acid; clear smooth boundary.
Bo2--22 to 31 inches; dusky red (10R 3/4) clay; weak medium subangular blocky structure; slightly hard, firm; slightly sticky, plastic; few distinct clay films on ped faces; few fine roots; few fine irregular pores; about 1 percent, by volume, iron-manganese concretions; moderately acid; gradual smooth boundary.
Bo3--31 to 43 inches; dusky red (10R 3/4) clay; weak medium subangular blocky structure; soft, friable; slightly sticky, slightly plastic; few distinct clay films on ped faces; few fine roots; few fine irregular pores; moderately acid; clear smooth boundary.
Bo4--43 to 80 inches; dusky red (10R 3/4) clay; weak medium subangular blocky structure; slightly hard, firm; slightly sticky, slightly plastic; common prominent clay films on ped faces; few fine roots; few fine irregular pores; strongly acid.
TYPE LOCATION: San German, Puerto Rico. Approximately 1.3 miles southwest of the intersection of P.R. Hwy. 120 and P.R. Hwy. 362, about 1.0 mile southwest of Campamento Santana on forest trail, and about 50 feet northwest of trail in forestland. USGS Maricao topographic quadrangle (1960); lat. 18 degrees 07 minutes 41 seconds N.; long. 66 degrees 58 minutes 30 seconds W.
RANGE IN CHARACTERISTICS: Solum thickness and depth to serpentinite rock is more than 80 inches. Fine iron concretions range from none to few throughout the profile. Base retention is 1 meq. /100 grams of clay in some subhorizon of the oxic. CEC is less than 16 meq/100 grams of clay in the Bo horizons. Organic matter content is less than 20 kilograms in a volume of 1 meter square to a depth of 1 meter. Reaction ranges from very strongly acid to moderately acid throughout.
The Oi horizon, where present, consists of decomposed material such as bark, branches, leaves, and twigs.
The A or Ap horizon has hue of 10R or 2.5YR, value of 2 or 3, and chroma of 2 to 6. Texture is clay.
The Bo horizon has hue of 7.5R to 2.5YR, value of 3 or 4, and chroma of 4 to 6. Cementation is common in areas that are devoid of vegetation and exposed to wetting and drying conditions. Texture is clay.
COMPETING SERIES: There are no known series in the same family.
GEOGRAPHIC SETTING: Nipe soils are on stable ridge tops of hills and mountains in the Humid Mountains and Valleys MLRA. Slopes range from 2 to 20 percent. They formed in iron-rich residuum weathered from serpentinite bedrock. The climate is humid tropical. The average annual precipitation ranges from 43 to 73 inches and the average annual temperature ranges from 73 to 77 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Delicias, El Cacique (T), La Taina (T), Maresua, Rosario, and Santa Marta series. Delicias and Rosario soils have a cation retention capacity of more than 1 meq. per 100 grams of clay in all parts of the oxic horizon. In addition, Delicias soils are on lower positions and have less clay in the control section while Rosario soils are moderately deep to serpentinite bedrock. El Cacique (T) and La Taina (T) soils are on more sloping positions, are shallow to serpentinite bedrock, and are Mollisols. Maresua and Santa Marta are moderately deep to serpentinite bedrock. In addition, Maresua and Santa Marta soils are nonacid, lack the red and dusky red colors, and have less weathered profiles. Maresua soils are Mollisols, Santa Marta soils are Ultisols.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Most areas of Nipe soils are in urban development, with some areas in forestland or naturalized pastureland. The vegetation consists of Brazil beauty-leaf, Clusia clusioides, Monkey-apple, Swamp cyrilla and Wild honey trees, and ferns.
DISTRIBUTION AND EXTENT: Stable ridge tops of hills and mountains of the southern Humid Mountains and Valleys MLRA of Puerto Rico. The series is of minor extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina.
SERIES ESTABLISHED: Mayaguez Municipality, Soil Survey of Puerto Rico; 1942.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Ochric epipedon - the zone from 2 to 11 inches (Ap and A horizons).
Oxic horizon - the zone from 11 to 80 inches (Bo1, Bo2, Bo3, and Bo4 horizons).
This soil formed in the Ks-Serpentinite Formation (Ks). It is a remnant of lateritic residual soil on serpentinite.
Nipe is a Benchmark soil series.
ADDITIONAL DATA: Characterization pedon - San German Municipality, Puerto Rico; S02PR-125-005. Sample by NSSL, Lincoln, NE., 07/2002.
Nipe soils are in MLRA 270.