LOCATION POLOVINA AK
Established Series
Rev. MJM/JPM
02/2022
POLOVINA SERIES
The Polovina series consists of deep, well-drained soils formed in medium textured material derived from pyroclastic deposits over gravelly residuum. Polovina soils are on dipslopes and plains near volcanic cones. Slopes range from 0 to 8 percent. Mean annual air temperature is about 35 degrees F. and the average annual precipitation is about 24 inches.
TAXONOMIC CLASS: Medial, amorphic Humic Vitricryands
TYPICAL PEDON: Polovina fine sandy loam - under forbs and grass vegetation at 120 feet (40 m) elevation. (All colors are for moist soil)
Oe - 0 to 2 inches (0 to 4 cm); very dark brown (7.5YR 2.5/3) mucky peat; common fine and medium roots; neutral (pH 6.6); clear smooth boundary. (2 to 4 inches thick)
A - 2 to 4 inches (4 to 9 cm); very dark brown (10YR 2/2) fine sandy loam; weak fine granular structure; very friable; non-sticky and non-plastic; common fine roots; weakly smeary; slightly acid (pH 6.4); clear wavy boundary. (2 to 5 inches thick)
Bw - 4 to 19 inches (9 to 49 cm); very dark brown (7.5YR 2.5/3) sandy loam; weak medium subangular blocky structure; friable; non-sticky and non-plastic; few fine roots; non-smeary; moderately acid (pH 6.0); gradual wavy boundary. (5 to 15 inches thick)
2BC - 19 to 37 inches (49 to 95 cm); dark olive brown (2.5Y 3/3) silt loam; moderate fine subangular blocky structure; friable; non-sticky and non-plastic; no roots; weakly smeary; moderately acid (pH 6.0); clear wavy boundary. (10 to 20 inches thick)
2C - 37 to 55 inches (95 to 140 cm); dark olive brown (2.5Y 3/3) gravelly silt loam; weak angular blocky structure; friable; non-sticky and non-plastic; weakly smeary; 25 percent gravel; slightly acid (pH 6.2); clear smooth boundary. (5 to 25 inches thick)
R - 55 inches (140 cm); brown (10YR 4/3) fractured basalt bedrock
TYPE LOCATION: Saint Paul Island Alaska; UTM Zone 2, 545884 E and 6334438 N.
RANGE IN CHARACTERISTICS: Thickness of the organic mat ranges from 1 to 3 inches. The weighted average substitute particle size of the control section is medial with greater than 30 percent coarse silt or coarser. Occasional thin strata of loamy sand or loamy fine sand occur between the Bw and the 2 BC horizons.
The A horizon, has hue of 5YR, 7.5YR, or 10YR; value moist of 2 or 2.5. Texture is fine sandy loam or very fine sandy loam.
The Bw horizon has hue of 5YR, 7.5YR, or 10YR; value moist of 2.5 or 3; chroma moist of 2 through 4. Texture is fine sandy loam, sandy loam, or very fine sandy loam. Reaction is moderately acid to slightly acid
The 2BC horizon has hue from 2.5Y to 10YR; value moist of 2.5 or 3; chroma moist of 2 or 3. Texture is silt loam or very fine sandy loam with occasional thin strata of loamy fine sand. Reaction is moderately acid to slightly acid
The 2C horizon has hue of 10YR, 7.5Y, 5YR, or 2.5Y; value moist of 3, 4, or 5 and chroma moist from 2 to 8. Texture is silt loam, very fine sandy loam, or gravelly silt loam. Gravel content ranges from 0 to 35 percent, cobble content ranges from 0 to 35 percent. Reaction is moderately acid to neutral.
COMPETING SERIES: none
GEOGRAPHIC SETTING: Polovina soils formed on dipslopes and plains near volcanic cones in coarse textured materials derived from scoria or other pyroclastic deposits reworked by wind and water with a residual substratum derived from basalt. Slopes range from 0 to 8 percent. The climate is cold maritime. Mean annual air temperature is 35 degrees F., and mean annual precipitation ranges from 19 to 28 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are
Tsammana series on lower footslopes and adjacent beach terraces,
Bogoslof series on terraces on plains and
Lukanin series on nearby dunes
DRAINAGE AND PERMEABILITY: Well drained. Slow to moderate runoff. Permeability is moderate.
USE AND VEGETATION: Mostly in grass and forbs dominated by Nootka lupine (Lupinus nootkatensis), Bering hairgrass (Deschampsia cespitosa), and Crowberry (Empetrum nigrum).
DISTRIBUTION AND EXTENT: Saint Paul Island, Alaska. The series is of limited extent.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: WASILLA, ALASKA
SERIES ESTABLISHED: Saint Paul Island, Alaska, 2000.
REMARKS: Diagnostic layers and features recognized in this profile include: An umbric epipedon and andic soil properties in at least 60 percent of the upper 24 inches from the mineral soil surface. A 1500 kPa water retention of between 12 and 15 percent on air-dried samples in 60 percent of the thickness between the mineral soil surface and 24 inches. (Undried samples have not been examined for water retention at 1500 kPa). In the mineralogy control section a sum of 8 times the silica plus 2 times the iron (percents by weight by acid oxalate) of 5 or more and 8 times the silica is more than 2 times the iron. A lithic contact between 40 and 60 inches depth, a cryic temperature regime.
National Cooperative Soil Survey
U.S.A.