LOCATION ICACOS PREstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, semiactive, acid, isothermic Aeric Endoaquepts
TYPICAL PEDON: Icacos loam - forest in Caribbean National Forest. (Colors are for moist soil conditions unless otherwise stated.)
A--0 to 4 inches; dark yellowish brown (10YR 4/4) loam; moderate fine granular structure; friable; many very fine, fine, medium and coarse roots, very strongly acid; clear smooth boundary. (1 to 14 inches thick)
Bw--4 to 14 inches; yellowish brown (10YR 5/4) silty clay loam; weak fine subangular blocky structure; friable; few fine roots; common medium distinct strong brown (7.5YR 5/6) masses of iron accumulation and gray (10YR 5/1) areas of iron depletions; very strongly acid; clear smooth boundary. (5 to 20 inches thick)
Cg1--14 to 23 inches; gray (10YR 5/1) silt loam; massive; few fine roots; common fine mica flakes; common medium distinct strong brown (7.5YR 5/6) masses of iron accumulation; very strongly acid; gradual smooth boundary.
Cg2--23 to 37 inches; greenish gray (5GY 5/1) silty clay loam; massive; few very fine roots; common fine mica flakes; common medium distinct red (2.5YR 4/6) masses of iron accumulation; very strongly acid; common fine mica flakes; abrupt smooth boundary.
Cg3--37 to 60 inches; olive gray (5Y 4/2) silt loam; massive; common fine mica flakes; common medium distinct yellowish red (5YR 5/6) and dark brown (10YR 3/3) masses of iron accumulation; very strongly acid.
TYPE LOCATION: Caribbean National Forest, Puerto Rico. Approximately 75 feet east of kilometer 16.5 of RD 191, on the west side of the Icacos flood plain. El Yunque topographic quadrangle; lat. 18 degrees 16 minutes 30 seconds N.; long. 65 degrees 47 minutes 57 seconds W.; PRD 1940.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 10 to 40 inches. Reaction ranges from extremely acid to strongly acid throughout the profile. Rock fragments range from 0 to 10 percent throughout the profile.
The A horizon has hue of 10YR or 2.5Y, value of 2 to 5 and chroma of 2 to 4; or it is neutral with value of 2 to 5. Texture is silt loam, loam, or clay loam.
The Bw horizon has hue of 10YR to 5Y, value of 4 to 6 and chroma of 3 to 6. Redoximorphic features in shades of yellow, brown, and gray range from few to common. Texture is silt loam, silty clay loam, or clay loam.
The Cg horizon has hue of 7.5YR to 5GY, value of 4 to 6 and chroma of 1 or 2; or there is no dominant matrix color and is multicolored in shades of gray, yellow, brown, and red. Redoximorphic accumulations in shades of yellow, brown, and red range from few to many. Texture is silt loam, sandy loam, loam, clay loam, silty clay loam or clay.
COMPETING SERIES: There are no competing series in the same family.
GEOGRAPHIC SETTING: Icacos soils are on mountain streams of deeply dissected uplands. They formed in alluvium that weathered from plutonic rocks. The climate is moist tropical. Slopes range from 0 to 15 percent. The average annual precipitation ranges from 150 to 200 inches and the average annual temperature ranges from 58 to 72 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the Picacho and Utuado soils. They are on higher adjacent upland positions. In addition, Picacho soils are moderately well drained and Utuado soils are well drained.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; moderate permeability.
USE AND VEGETATION: Watershed protection, recreation, research, and wildlife habitat. Forested with over 200 woody species.
DISTRIBUTION AND EXTENT: Caribbean National Forest, Puerto Rico. The series is of minor extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina.
SERIES ESTABLISHED: Caribbean National forest and Luquillo Experimental Forest, Puerto Rico, 1992.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Ochric epipedon - the zone from 0 to 4 inches (A horizon).
Cambic horizon - the zone from 4 to 14 inches (Bw horizon).
Acid feature - very strongly acid reaction from 10 to 40 inches (Bw and 2BC horizons).
Aquic feature - apparent water table; 0.5 to 1.0 feet; April through December.