LOCATION PERCHAS PREstablished Series
TAXONOMIC CLASS: Fine, smectitic, isohyperthermic Chromic Dystraquerts
TYPICAL PEDON: Perchas clay - native pasture.
(Colors are for moist soil.)
Ap--0 to 5 inches; dark grayish brown (10YR 4/2) clay with few medium distinct gray (10YR 5/1) few fine prominent greenish gray (5GY 6/1) and few fine prominent dark greenish gray (5BG 4/1) mottles; weak medium and coarse subangular blocky structure; firm, slightly sticky, plastic; many fine roots; rust color due to root decay; very strongly acid; abrupt smooth boundary. (4 to 6 inches thick)
B2g--5 to 12 inches; light gray (5Y 7/2), light brownish gray (10YR 6/2), and light yellowish brown (10YR 6/4) clay with few fine prominent greenish gray (5GY 6/1) mottles; weak medium and coarse subangular blocky structure; firm, slightly sticky, plastic; commonfine roots; very strongly acid; clear wavy boundary. (5 to 9 inches thick)
B3g--12 to 19 inches; light gray (10YR 7/2) and greenish gray (5GY 5/1) clay with common fine strong brown (7.5YR 5/6) mottles; weak coarse subangular blocky structure; firm, slightly sticky, plastic; few fine roots; very strongly acid; clear wavy boundary. (5 to 11 inches thick)
C1g--19 to 28 inches; light gray (10YR 7/2) clay with many fine prominent strong brown (7.5YR 5/6) mottles; massive, firm, slightly sticky, plastic; very strongly acid; clear wavy boundary. (7 to 10 inches thick)
C2g--28 to 40 inches; light gray (10YR 7/2) clay with few medium prominent greenish gray (5BG 5/1) and common fine prominent strong brown (7.5YR 5/6) mottles; massive; firm, slightly sticky, plastic; very strongly acid.
TYPE LOCATION: Culebrinas SCD, Puerto Rico, 3 miles west of the town of Lares. 350 meters south of kilometer marker 32.9 on Highway 111, on paved, unnumbered road, 25 meters west of road.
RANGE IN CHARACTERISTICS: Thickness of the solum ranges from 14 to 26 inches. Texture is clay in the whole profile. Consistence is slightly sticky or sticky and plastic. Structure is weak, fine to coarse subangular blocky in the cambic horizon. Reaction is strongly to extremely acid throughout. Organic matter content decreases regularly with depth. The mean annual soil temperature is 75 degrees F.
The A horizon has hues of 7.5YR or 10YR, values of 4 or 5, and chromas of 1 to 2. Mottles are gray, greenish gray or dark greenish gray. Structure is weak or medium subangular blocky.
The B horizons are gleyed with 60 percent or more by volume of the matrix as low chroma. Hues are 5Y, 10YR, or 2.5Y, values of 5 to 7, and chroma of 2 or less. Structure is weak, fine to coarse subangular blocky.
The C horizon is also gley with hues of 2.5Y, 5Y, or 10YR, chroma of 2 or less in more than 60 percent by volume of the matrix.
COMPETING SERIES: The Maunabo series is in the same family. The Bajura, Coloso, Corcega, Fortuna, Guayabota, Igualdad, Jareales, Pinones, Reparada, Santoni, Talante, Vayas and Vigia series are similar soils in related families. Maunabo soils have coarser textured lower horizons. The Bajura and Santoni soils have horizons with COLE values of more than 0.09 in their profiles. The Coloso, Corcega and Talante soils are better drained and have less than 60 percent by volume of the upper 30 inches with low chroma mottles. The Corcega and Talante soils have coarser textured profiles. The Fortuna and Vayas soils have organic matter content that does not decrease regularly with depth. The Guayabota soils are shallow to the rock and have colder mean annual soil temperatures. The Igualdad are coarser textured in the lower horizons and are less acid. The Jareales, Pinones, Reparada and Vigia soils all have organic layer with their profiles.
GEOGRAPHIC SETTING: The Perchas soils are gently sloping and moderately steep soils on foot slopes and low rolling hills on slopes ranging from 2 to 20 percent. The regolith formed in fine textured sediments over Tertiary clays. The climate is humid tropical. The average annual precipitation ranges from 80 to 90 inches and the mean annual temperature is 77 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Moca, Voladora and Plata series. The Moca and Voladora soils are redder and better drained. The Plata soils are coarser textured and have a conglomerate of cobbles, sands and clays in the substrata.
DRAINAGE AND PERMEABILITY: Poorly drained, runoff is medium and permeability is slow.
USE AND VEGETATION: Most of the acreage is in native pasture. Small acreage is in sugarcane and coffee.
DISTRIBUTION AND EXTENT: Humid northern uplands of Puerto Rico. The series is of minor extent, with about 5,000 acres.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina
SERIES ESTABLISHED: Culebrinas SCD, Puerto Rico; 1979.