LOCATION LA TAINA PREstablished Series
TAXONOMIC CLASS: Clayey-skeletal, magnesic, isohyperthermic, shallow Typic Argiudolls
TYPICAL PEDON: La Taina very gravelly clay--naturalized pastureland (Colors for moist soil unless otherwise indicated.)
Ap--0 to 8 inches; very dark brown (10YR 2/2) very gravelly clay; moderate fine subangular blocky structure parting to moderate fine granular structure; slightly hard, friable; slightly sticky, slightly plastic; many fine and medium roots, few coarse roots; common fine interstitial pores; about 40 percent, by volume, pebbles; neutral; clear smooth boundary. (3 to 8 inches)
Bt1--8 to 13 inches; dark reddish brown (5YR 3/2) extremely gravelly clay; moderate fine subangular blocky structure parting to weak fine granular structure; slightly hard, firm; sticky, plastic; common fine and medium roots; common fine interstitial and few fine tubular pores; few faint clay films on faces of peds; about 60 percent, by volume, pebbles; about 10 percent, by volume, cobbles; neutral; clear smooth boundary.
Bt2--13 to 17 inches; dark reddish brown (5YR 3/2) extremely paragravelly clay loam, weak fine subangular blocky structure; slightly hard, firm; sticky, plastic; common fine medium roots; common fine interstitial pores; common faint clay films on faces of peds; about 75 percent, by volume, parapebbles; about 10 percent, by volume, paracobbles; neutral; abrupt smooth boundary. (Combined thickness of the Bt horizons range from 7 to 12 inches)
Cr--17 to 29 inches; Highly fractured serpentinite bedrock.
R--29+ inches; Hard consolidated serpentinite bedrock.
TYPE LOCATION: San German Municipality, Puerto Rico. Approximately 1.7 miles northeast of downtown San German; about 0.5 mile southeast on P.R. Highway 2 from the intersection of P.R. Highway 362, and about 100 feet northeast of P.R. Highway 2 on pasture field. USGS Quadrangle San German, Puerto Rico (1966). Lat. 18 degrees 05 minutes 03 seconds N.; long. 67 degrees 01 minute 07 seconds W.
RANGE IN CHARACTERISTICS: Solum thickness and depth to highly fractured serpentinite bedrock ranges from 10 to 20 inches. Depth to consolidated serpentinite bedrock ranges from 18 to 29 inches. Reaction is neutral throughout. Rock fragments include pebbles and cobbles composed of serpentinite. The combined total of rock fragments in the control section is more than 35 percent, by volume.
The A horizons has hue of 7.5YR or 10YR, value of 2 or 3, and chroma of 2 or 3. Texture is clay loam or clay in the fine-earth fraction. Content of pebbles and cobbles ranges from 8 to 65 percent, by volume.
The Bt horizons have hue of 5YR or 7.5YR, value of 3, and chroma of 2 or 3. Texture is clay loam or clay in the fine-earth fraction. Content of pebbles and cobbles range from 60 to 85 percent, by volume.
The Cr horizon is composed of highly fractured serpentinite. It can be excavated with difficulty with hand tools, and rippable by mechanized equipment.
The R horizon is composed of hard consolidated serpentinite bedrock.
COMPETING SERIES: There are no other known series in the same family.
GEOGRAPHIC SETTING: La Taina soils are on summits and side slopes in serpentinite hills and mountains of the Humid Mountains and Valleys MLRA of southern Puerto Rico. Slopes range from 5 to 90 percent. They formed in material that weathered from serpentinite bedrock. The climate is humid tropical. The average annual air temperature ranges from 80 to 82 degrees F., and the average annual precipitation ranges from 78 to 82 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the El Cacique (T), Maresua, Nipe, Rosario and Santa Marta soils. All of these soils are on similar positions. El Cacique soils are in the clayey family. Maresua soils are moderately deep to serpentinite bedrock. Nipe, Rosario, and Santa Marta soils are redder, finer textured, and do not have the large amount of rock fragments throughout the profile. In addition, the Nipe and Rosario soils are acid and have an oxic horizon.
DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability.
USE AND VEGETATION: Most areas of La Taina soils are used for forestland, grazing or habitat for wildlife. The vegetation consists of Maricao doncella, Cupey del monte and Algarrobo trees; Cariaquillo, Leucaena, Arbol de navidad del pobre and Carrasco shrubs; and lamina and guinea grasses.
DISTRIBUTION AND EXTENT: Summits and side slopes of the serpentinite hills and mountains of southern Puerto Rico. This series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina.
SERIES ESTABLISHED: San German Municipality, Puerto Rico, 2007.
REMARKS: La Taina soils were formerly included in the Maresua series and the Serpentinite outcrop miscellaneous land type.
Diagnostic horizons and features recognized in this pedon include:
Mollic epipedon - The zone from 0 to 8 inches (Ap horizon)
Argillic horizon - The zone from 8 to 17 inches (Bt1 and Bt2 horizons).
Paralithic contact - The contact at 17 inches (Cr horizon).
Lithic contact - The contact at 29 inches (R horizon).
ADDITIONAL DATA: Characterization pedon- San Germn Municipality, Puerto Rico; S88PR125-001. Sample by the NSSL, Lincoln, NE.
La Taina soils are in MLRA 270.