LOCATION GUERRERO PREstablished Series
TAXONOMIC CLASS: Loamy, siliceous, subactive, isohyperthermic Arenic Plinthic Paleudalfs
TYPICAL PEDON: Guerrero sand--pasture and coconuts (Colors are for moist soil).
A1--0 to 10 inches; dark grayish brown (10YR 4/2) sand; grayish brown (10YR 5/2) dry; single grain; loose; nonsticky, nonplastic; many fine roots; moderately acid; clear smooth boundary.
A2--10 to 22 inches; brown (7.5YR 4/4) sand; single grain; loose; nonsticky, nonplastic; many fine roots; few fine soft black (10YR 2/1) concretions; moderately acid; clear smooth boundary. (Combined thickness of the A horizons range from 16 to 30 inches)
Bt1--22 to 28 inches; yellowish red (5YR 4/6) loamy sand; single grain; loose; nonsticky, nonplastic; few fine roots; few fine soft black (10YR 2/1) concretions; moderately acid; clear smooth boundary. (4 to 10 inches thick).
Bt2--28 to 36 inches; yellowish red (5YR 4/6) sandy clay; weak coarse subangular blocky structure; firm; slightly sticky, slightly plastic; few fine roots; few fine soft black (10YR 2/1) concretions; many fine quartz grains; many distinct clay films on ped faces; strongly acid; clear wavy boundary. (Thickness of the Bt horizons range from 10 to 20 inches).
Btv1--36 to 44 inches; strong brown (7.5YR 5/8) clay; weak coarse subangular blocky structure; firm; slightly sticky, plastic; many distinct clay films on ped faces; few fine soft black (10YR 2/1) concretions; many fine quartz grains; about 15 percent, by volume, plinthite; common fine prominent red (2.5YR 4/8) and few fine faint brown (7.5YR 4/4) masses of iron accumulation; strongly acid; clear wavy boundary.
Btv2--44 to 50 inches; strong brown (7.5YR 5/8) clay; weak coarse subangular blocky structure; firm; slightly sticky, slightly plastic; many fine quartz grains; common faint clay films on ped faces; about 15 percent, by volume, plinthite; common medium distinct yellowish brown (10YR 5/6), common fine and medium prominent dark red (2.5YR 3/6) masses of iron accumulations; common medium prominent light gray (10YR 7/1) areas of iron depletions; very strongly acid; gradual wavy boundary.
Btv3--50 to 80 inches; yellowish brown (10YR 5/8) clay; weak coarse subangular blocky structure; firm; slightly sticky, slightly plastic; many fine quartz grains; common faint clay films on ped faces; about 8 percent, by volume, plinthite; few fine prominent dark red (2.5YR 3/6) masses of iron accumulation; common medium prominent light gray (10YR 7/1) areas of iron depletions; very strongly acid.
TYPE LOCATION: Noroeste SCD, Puerto Rico; approximately 1.0 mile west of the town of Isabela, about 80 feet north and 30 feet west of kilometer marker 1.7 of P.R. Highway 459.
RANGE IN CHARACTERISTICS: Thickness of the solum is more than 50 inches. Reaction ranges from very strongly acid to moderately acid throughout, except where the surface has been limed.
The A or Ap horizon has hue of 7.5YR or 10YR, value of 3 or 4, and chroma of 2 to 4. Where value is 3, it is less than 7 inches thick. Texture is sand.
The E horizon, where present, has hue of 7.5YR, value of 4 or 5, and chroma of 2 to 4. Texture is sand.
The Bt horizon has hue of 5YR or 7.5YR, value of 4 and 5, and chroma of 6 to 8. Texture is loamy sand, sandy loam, sandy clay loam, or sandy clay.
The Btv horizon has hue of 5YR or 7.5YR, value of 4 and 5, and chroma higher than 6. Redoximorphic features in shades of red, brown, and gray range from few to many. Content of plinthite ranges from 5 to 20 percent, by volume. Texture is sandy clay or clay.
COMPETING SERIES: These are no known series in the same family.
GEOGRAPHIC SETTING: Guerrero soils are on coastal plain uplands. Slopes range from 0 to 5 percent. They formed in regolith that consists of coarse material over fine-textured sediments. The climate is humid tropical. The average annual precipitation ranges from 55 to 65 inches and average annual temperature ranges from 74 to 76 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the Jobos, Maleza, and Rio Lajas series. The moderately well drained Jobos soils are on lower positions, have sandy surface and subsurface layers less than 20 inches thick, and have more clay in the subsoil. Maleza soils are on similar to lower positions, have sandy surface and subsurface layers less than 20 inches thick, have redder and more clay in the subsoils, and lack plinthite. The somewhat excessively drained Rio Lajas soils are on lower positions, have Umbric epipedons, have less clay in the subsoil, and lack plinthite.
DRAINAGE AND PERMEABILITY: Well drained; rapid permeability in the surface horizons and moderately slow in the subsoil.
USE AND VEGETATION: Most areas of Guerrero soils are used for native pasture and subsistence crops. The vegetation consists of native and introduced grasses, shrubs, and trees.
DISTRIBUTION AND EXTENT: Humid coastal plains of Puerto Rico. The series is of minor extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina.
SERIES ESTABLISHED: Norosete SCD, Puerto Rico; Guerrero is the name of a "barrio" where the series was first recognized.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Ochric epipedon - the zone from 0 to 22inches (A1 and A2 horizons).
Argillic horizon - the zone from 22 to 80 inches (Bt1, Bt2, Btv1, Btv2, and Btv3 horizons).
Plinthic horizon - the zone from 36 to 80 inches (Btv1, Btv2, and Btv3 horizons).
Arenic feature - the zone from 0 to 22 inches (A1 and A2 horizons).
Classification was changed to recognize the presence of plinthite.
These soils were formerly mapped in the Guayabo series but differ from it being usually moist and not having a subhorizon from 7 to 20 inches dry for as much as 60 consecutive days in most years.
Supporting data: Lab Characterization Sample Number 87PR-071-002. Lab data by NSSC, Lincoln, NE.