LOCATION PARTOV AK
Inactive Series
Rev. WRF
02/2022
PARTOV SERIES
The Partov series consists of shallow, well-drained soils formed in volcanic ash, cinders, and fragmented basalt. Partov soils are on ridges and knolls of hilly uplands and have slopes of 2 to 30 percent. The mean annual precipitation is 55 to 65 inches, and the mean annual air temperature is about 41 degrees F.
TAXONOMIC CLASS:
TYPICAL PEDON: Partov-very gravelly silt loam, rangeland. (Colors are for moist soil)
02--1 to 0 inches; black (10YR 2/1) well-decomposed plant litter with an admixture of about 20 percent ash; abrupt smooth boundary.
A11--0 to 2 inches; dark reddish brown (5YR 3/2) very gravelly silt loam; weak very fine granular structure; silt loam is very friable, smeary, common roots; slightly acid, clear wavy boundary.
A12--2 to 4 inches; dark reddish brown (5YR 3/3) very stony silt loam, weak very fine granular structure; silt loam is very friable, smeary; few roots; slightly acid; gradual boundary.
A13--4 to 15 inches, dark reddish brown (5YR 3/4) very stony silt loam; massive; very friable, smeary; few roots; slightly acid; abrupt wavy boundary.
IIR--15 inches; basalt bedrock.
TYPE LOCATION: Umnak-Unalaska Area Alaska; about 6 miles west of Kettle Cape, Umnak Island; Approx Lat. 53 degrees 17 N, Long. 168 degrees 16 W.
RANGE IN CHARACTEISTICS: The mean annual soil temperature is estimated to range from 40 degrees to 44 degrees F. The soil is always moist. Depth to basalt bedrock ranges from 10 to 20 inches. Texture of the fine earth fraction (volcanic ash) ranges from fine sandy loam to silt loam. The control section averages 60 to 80 percent basalt rock fragments by volume. Colors throughout the profile have hues of 5YR to 10YR with values of 2 or 3 moist, and chromas of 1 through 4 moist. Reaction is slightly acid to neutral.
COMPETING SERIES: These are the
Pyramid series of the same subgroup, and the Aslik, Okmok, and
Tolstoi series. The Pyramid soils have a layer of recent volcanic ash at the surface and have less than 35 percent (by volume) of coarse fragments in the upper part of the soil. The Aslik soils have a substratum of cindery materials. The Okmok soils are dominantly monthixotropic and are 20 to 40 inches thick over bedrock. The Tolstoi soils are very strongly acid and have a spodic horizon.
GEOGRAPHIC SETTING: Partov soils are on ridges and knolls of hilly uplands in the vicinity of active volcanoes and have slope gradients of 2 to 30 percent. They formed in volcanic ash, cinders, and fragmented basalt. Elevations range from 200 to 3000 feet. The climate is maritime, with cool summers and mild winters. The mean annual precipitation is 55 to 65 inches The mean annual air temperature is 41 degrees F, the mean January temperature is 33 degrees F.; the mean July air temperature is 52 derees F.; and the average growing season is 145 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Aslik and Okmok series, an the ulik and
Umnak series. The
Tulik soils are stratified and consist dominantly of thixotropic materials. The Umnak soils are stratified and consist dominantly of ashy materials.
DRAINAGE AND PERMEABILITY: Well-drained; slow to medium runoff, moderate permeability.
USE AND VEGETATION: Used for rangeland. The vegetation consists mostly of grasses, low growing forbs, and shrubs. Princioal plants are bluejoint reedgrass, purple reedgrass, sedges, woodrush, alpine timothy, fescue, lupine, fireweed, yarrow, parsley, and willows.
DISTRIBUTION AND EXTENT: Alaska Peninsula and Aleutian Islands. The series probably is of moderate extent.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: WASILLA, ALASKA
SERIES PROPOSED: Umnak Area, Alaska, 1977. (Source of name is Partov cove, Umnak Island)
REMARKS:- Soil Sample No. S76AK-26-5.
OSED scanned by SSQA. Last revised by state on 01/77.
National Cooperative Soil Survey
U.S.A.