LOCATION LOS GUINEOS PR
Established Series
SRT/MMR/AMA
06/2022
LOS GUINEOS SERIES
MLRA(s): 270
MLRA Soil Survey Regional Office (SSRO) Responsible: Raleigh, North Carolina
Depth Class: Very deep
Drainage Class: Well drained
Saturated Hydraulic Conductivity: Moderately high or high
Parent Material: Residuum from Hato Puerco lava formation.
Slope: 5 to 60 percent
Mean Annual Air Temperature: 16 to 21 degrees C. (61 to 70 degrees F.)
Mean Annual Precipitation: 3,556 to 5,436 millimeters (140-214 inches)
TAXONOMIC CLASS: Very-fine, kaolinitic, isothermic Humic Haploperox
TYPICAL PEDON: Los Guineos clay - Palo Colorado forest in El Yunque National Forest. (Colors are for moist conditions.)
A--0 to 3 centimeters (0 to 1 inch); dark yellowish brown (10YR 4/4) clay; moderate fine and medium granular structure; friable; moderate sticky, moderate plastic; many continuous faint organic stains on all faces of peds; common very fine and fine roots throughout; few fine tubular pores throughout; extremely acid; clear smooth boundary. (3 to 13 centimeters (1 to 5 inches thick)).
AB--3 to 8 centimeters (1 to 3 inches); yellowish brown (10YR 5/4) clay; moderate fine subangular blocky structure; friable; very sticky, very plastic; few fine cylindrical worm casts on faces of peds; few fine continuous faint clay films on all faces of peds; common fine and medium continuous distinct clay films on all faces of peds; common fine and medium roots throughout; common very fine tubular pores throughout; extremely acid; clear smooth boundary.
Bto1--8 to 23 centimeters (3 to 9 inches); yellowish brown (10YR 5/6) clay; moderate medium and coarse subangular blocky structure; firm; very sticky, very plastic; few fine cylindrical worm casts on faces of peds; many continuous distinct clay films on all faces of peds; common fine and medium roots throughout; common fine and medium tubular pores throughout; extremely acid; clear smooth boundary.
Bto2--23 to 46 centimeters (9 to 18) inches; brownish yellow (10YR 6/6) clay; moderate coarse subangular blocky structure; firm; very sticky, very plastic; common fine prominent red (2.5YR 4/6) masses of iron accumulation on faces of peds; few fine cylindrical worm casts on faces of peds; many continuous distinct clay films on all faces of peds; common fine and medium roots throughout; few fine tubular pores throughout; extremely acid; clear wavy boundary.
Bto3--46 to 79 centimeters (18 to 31 inches); red (2.5YR 4/6) clay; moderate medium and coarse subangular blocky structure; firm; very sticky, very plastic; many coarse prominent yellowish brown (10YR 5/6) masses of iron accumulation on faces of peds; few fine cylindrical worm casts on faces of peds; many continuous distinct clay films on all faces of peds; few fine roots throughout; few medium tubular pores throughout; very strongly acid; gradual smooth boundary. (Combined thickness of the Bto horizons range from 64 to 127 centimeters, 25 to 50 inches)
Bt1--79 to 109 centimeters (31 to 43 inches); red (2.5YR 4/6) silty clay; weak coarse subangular blocky structure; firm; very sticky; very plastic; common medium distinct yellowish brown (10YR 5/6) masses of iron accumulation on faces of peds; few distinct clay films on all faces of peds; few fine roots throughout; few medium tubular pores throughout; very strongly acid; gradual smooth boundary.
Bt2--109 to 155 centimeters (43 to 61 inches); strong brown (7.5YR 5/6) silty clay loam; weak very coarse subangular blocky structure; firm; moderate sticky, moderate plastic; many medium distinct yellowish red (5YR 4/6) and few medium distinct yellowish brown (10YR 5/6) masses of iron accumulation on faces of peds; common faint clay films on vertical faces of peds; few fine roots throughout; few medium tubular pores throughout; very strongly acid; clear smooth boundary. (Combined thickness of the Bt horizons range from 38 to 102 centimeters, 15 to 40 inches)
BCt--155 to 203 centimeters (61 to 80 inches); strong brown (7.5YR 5/6) silt loam; weak very coarse subangular blocky structure; firm; moderate sticky, moderate plastic; many medium distinct yellowish red (5YR 4/6) masses of iron accumulation on faces of peds; few continuous distinct clay films on surfaces along root and pores channels; few medium tubular pores throughout; about 10 percent, by volume, highly weathered saprolite material; very strongly acid; gradual smooth boundary.
TYPE LOCATION: Rio Grande Municipality, Northeast SWCD; El Yunque National Forest, Puerto Rico. Approximately 0.57 mile southwest of the intersection of P.R. Hwy. 186 and forest gravel road # 12; about 0.15 mile northwest from the end of the forest road #12 nearby Rio Espritu Santo old bridge. El Yunque topographic quadrangle; Latitude: 18 degrees 18 minutes 47 seconds north, Longitude: 65 degrees 49 minutes 27 seconds west NAD83.
RANGE IN CHARACTERISTICS:
Thickness of the solum: More than 152 centimeters (60 inches)
Oxic horizon thickness: 64 to 127 centimeters (25 to 50 inches)
Rock fragments: Range from 0 to 10 percent, by volume, throughout the profile. Stones and cobbles range from 0 to 15 percent on the surface.
Soil Reaction: from extremely acid to strongly acid throughout the profile
Range of Individual Horizons:
A horizon:
Color - Hue of 7.5YR or 10YR, value and chroma of 3 or 4
Texture - clay loam or clay in the fine-earth fraction
AB horizon:
Color - Hue of 7.5YR or 10YR, value of 3 to 5, and chroma 2 to 4
Texture - clay in the fine-earth fraction
Bto horizons:
Color - Hue of 2.5YR to 10YR, value of 4 to 6, and chroma of 4 to 8
Texture - clay in the fine-earth fraction
Bt horizons:
Color - Hue of 2.5YR to 7.5YR, value of 4 to 6 and chroma of 6 to 8
Texture - silty clay loam, silty clay, or clay in the fine-earth fraction
BCt or BC horizon:
Color - Hue of 2.5YR to 7.5YR, value of 4 to 6 and chroma of 6 to 8
Texture - silty clay loam, silty clay, or clay in the fine-earth fraction
Saprolite ranges from 0 to 20 percent, by volume
COMPETING SERIES: There are no competing series in the same family.
GEOGRAPHIC SETTING:
Landscape: Humid Mountains and Valleys of Puerto Rico (MLRA 270)
Landform: Los Guineos soils are on mountaintops and mountainflanks of Sierra de Luquillo in El Yunque National Forest
Parent Material: They formed in highly weathered residuum from Hato Puerco lava formation.
Mean Annual Air Temperature: 16 to 21 degrees C. (61 to 70 degrees F.).
Mean Annual Precipitation: 3,556 to 5,436 millimeters (140 to 214 inches).
GEOGRAPHICALLY ASSOCIATED SOILS:
These include the
Moteado,
Yunque, and
Zarzal soils.
Moteado soils--are deep to bedrock and have water tables and hydric soil morphology in their soil profiles.
Yunque soils--have less clay in the control section and have water tables closer to the soil surface than Los Guineos
Zarzal soils--have isohyperthermic temperature regime, udic moisture regime and occur on much steeper side slopes.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: Well drained
Saturated hydraulic conductivity: Moderately high or high
USE AND VEGETATION:
Major uses: Watershed protection, recreation, research, agriculture and wildlife habitat.
Dominant vegetation: Most of the areas are in El Yunque National Forest and are forested.
DISTRIBUTION AND EXTENT:
Humid Central Mountain Range and Valley Region of Puerto Rico.
The series is of small extent.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Raleigh, North Carolina.
SERIES ESTABLISHED: Puerto Rico, 1936.
REMARKS:
Diagnostic horizons and features recognized in this pedon:
1. Ochric epipedon - zone from 0 to 8 centimeters (0 to 3 inches, A and AB horizons).
2. Oxic horizon - zone from 8 to 79 centimeters (3 to 31 inches, Bto horizons).
3. Non-Argillic horizon - zone from 8 to 203 centimeters (3 to 80 inches, Bto, Bt, and BCt horizons).
4. Clay illuviation evidence is present but according to Soil Taxonomy and Lab data does not meet the required characteristics for the argillic or kandic horizons. This horizon needs at least 8 percent or more (absolute) clay than above horizon if that horizon has more than 40 percent total clay in the fine-earth fraction.
ADDITIONAL DATA:
Characterization data - Caribbean National Forest, Puerto Rico. Pedon No. 86P0303 and Soil Survey No. S1986PR119010. Sample by NSSL, Lincoln NE, 1986.
Los Guineos soils are in MLRA 270A and in the perudic moisture regime.
National Cooperative Soil Survey
U.S.A.