LOCATION UGAK                    AK

Established Series
Rev. SR
02/2022

UGAK SERIES

The Ugak series consists of deep, very poorly drained soils formed in volcanic ash deposits in depressional areas on moraines. Slopes range from 0 to 12 percent. Mean annual temperature is about 40 degrees F., and the average annual precipitation is about 60 inches.

TAXONOMIC CLASS: Coarse-loamy, acid Aquandic Cryaquepts

TYPICAL PEDON: Ugak silt loam -- under native grasses and sedge (All colors are for moist soil)

Oi--1 1/2 inches to 0; dark brown (7.5YR 3/2) mat of partially decayed organic materials; abrupt smooth boundary. (1 to 4 inches thick)

C--0 to 6 inches; light yellowish brown (10YR 6/4) silt loam volcanic ash; massive; firm in place, very friable disturbed; mottled with yellowish red and few light gray streaks; few roots; strongly to medium acid. (4 to 8 inches thick)

2C--6 to 10 inches; light brownish gray (10YR 6/2) loamy fine sand volcanic ash; single grained; loose; mottled with yellowish red; few roots; strongly acid; abrupt smooth boundary. (4 to 8 inches thick)

3O1b--10 to 11 inches; dark brown (10YR 3/3) peat mat of roots and leaves; very strongly acid; abrupt smooth boundary. (0 to 1 inch thick)

3A1b--11 to 15 inches; black (10YR 2/1) silt loam; non-sticky; many roots; few rock fragments; strongly acid; 3 to 5 inches thick.

3A2b--15 to 19 inches; dark reddish brown (5YR 3/3) silt loam, containing angular rock fragments; slightly sticky; medium acid. (4 to 6 inches thick)

3Cb--19 to 32 inches; olive (5Y 4/3) silt loam, streaked with dark brown and black; slightly sticky; strongly to medium acid.


TYPE LOCATION: Northeastern Kodiak Island Area, Alaska. Chiniak Cape Road, 1.3 miles west of junction with Pasagshak Bay Road at Kalsin Bay.

RANGE IN CHARACTERISTICS: Thickness of recent volcanic ash ranges from a few inches to 15 inches, but the normal range in thickness is 9 to 15 inches. Angular cobbles may occur in the buried horizons.

COMPETING SERIES: These are the Kalsin, Olds, and Salonie series in the same subgroup. Kalsin, Olds, and Salonie soils have sandy-skeletal materials in the lower part of the control section.

GEOGRAPHIC SETTING: Ugak soils occupy narrow depressions in moraines. The soils are formed in thick deposits of volcanic materials over glacial till. The climate is cool maritime. Average annual precipitation ranges from 50 to 70 inches, and the average annual temperature is about 40 degrees F. Temperatures below freezing are recorded on fewer than 40 days annually, and temperatures above 70 degrees F. are rare.

GEOGRAPHICALLY ASSOCIATED SOILS: These include the Kodiak and Saltery soils. Kodiak soils have deep water tables and are shallow over glacial till. Saltery soils are deep sedge peats.

DRAINAGE AND PERMEABILITY: Very poorly drained. Moderate permeability. Runoff is slow to medium.

USE AND VEGETATION: Used as range land. The native vegetation consists of water-tolerant grasses and sedges, alder, and, in a few places, Sitka spruce.

DISTRIBUTION AND EXTENT: Northern Kodiak Island, Alaska, and adjacent islands. The series is of moderate extent.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: WASILLA, ALASKA

SERIES ESTABLISHED: Northeastern Kodiak Island Area, Alaska, 1959.

REMARKS: The range in characteristics for the Sharatin series is poorly defined, especially in regards to the nature of the underlying material. More data is needed to define the central concept or the series should be inactivated (jpm, 4/87).

---

National Cooperative Soil Survey
U.S.A.