LOCATION SOKOLOF                 AK

Established Series
Rev. EJK-JPM
02/2022

SOKOLOF SERIES

The Sokolof series consists of very deep, well drained organic soils formed in extremely gravelly beach deposits. Sokolof soils are on uplifted beach terraces. Slopes range from 0 to 15 percent. Mean annual air temperature is about 41 degrees F. Mean annual precipitation is about 100 inches.

TAXONOMIC CLASS: Dysic Typic Cryofolists

TYPICAL PEDON: Sokolof mucky peat - on a south facing slope of 2 percent under second growth spruce-hemlock forest. (All colors are for moist soil).

Oe--0 to 2 inches; very dusky red (2.5YR 2.5/2) mucky peat consisting of partially decomposed forest litter; 50 percent fiber, 35 percent rubbed; many fine, common medium, and few coarse roots; extremely acid (pH 3.7 Truog); abrupt smooth boundary. (1 to 3 inches thick).

Oa1--2 to 6 inches; black (N 2/0) muck; decomposed forest litter; 20 percent fiber, 7 percent rubbed; 10 percent gravel; many fine and medium and few coarse roots; extremely acid (pH 3.5 Truog); abrupt wavy boundary. (2 to 8 inches thick).

Oa2--6 to 21 inches; black (5YR 2.5/1) extremely gravelly muck; 5 percent fiber, trace rubbed; 75 percent gravel, 10 percent cobbles; many fine and medium roots; extremely acid (pH 4.1 Truog); abrupt irregular boundary. (10 to 20 inches thick).

Oa3--21 to 60 inches; black (5YR 2.5/1) extremely gravelly muck; 5 percent fiber, trace rubbed; 85 percent gravel, 10 percent cobbles; organic material partially fills interstices between coarse fragments; few fine roots in organic material; extremely acid (pH 4.4 Truog).

TYPE LOCATION: South Zarembo Island, in NW 1/4, section 7, T.65S., R.81E., Copper River Meridian.

RANGE IN CHARACTERISTICS: Mean annual soil temperature ranges from 38 to 42 degrees F. Coarse fragment content ranges from 0 to 15 percent in the upper horizons (Oe and Oa1 horizons), which are comprised primarily of decomposing forest litter. Coarse fragment content ranges from 70 to 90 percent in the lower horizons where the organic material fills or partially fills the interstices between rock fragments. Rock fragments are primarily gravel size with some cobble. The soil does not freeze in most years due to maritime influence. Reaction is less than 4.5 (0.01M CaCl2) throughout the control section.

The organic material has hue ranging from 2.5YR to 10YR, value of 2 or 3 and chroma from 0 to 2. Thin mineral horizons, up to 1 inch thick, are present in the control section of some pedons.

COMPETING SERIES: These are the Annahootz (AK), Reggad (WA), and Tebenkof (AK) series. Annahootz soils have only stone and boulder size coarse fragments. Reggad soils have volcanic ash and pumice in the organic layers. The concept and range of the tentative Tebenkof series is covered by the Sokolof series.

GEOGRAPHIC SETTING: Sokolof soils occur on low uplifted beaches adjacent to the sea. The soils formed in gravelly beach deposits with the interstices filled with organic material. The climate is humid maritime with mean annual precipitation about 100 inches and mean annual air temperature of about 41 degrees F. Slope gradient ranges from 0 to 15 percent. Elevation ranges from sea level to 100 feet.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Blashke and the Karheen soils. Blashke soils are mineral soils with spodic horizons on similar landforms. Karheen soils are on slightly lower positions and are very poorly drained.

DRAINAGE AND PERMEABILITY: Well drained. Very slow runoff. Permeability is rapid.

USE AND VEGETATION: The Sokolof series is used for timber production, wildlife habitat and recreation. Overstory vegetation is dominantly western hemlock and Sitka spruce. Understory vegetation is dominantly blueberry, red huckleberry and rusty menziesia.

DISTRIBUTION AND EXTENT: Southeast Alaska. The series is not extensive.

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

SERIES ESTABLISHED: Stikine Area, Alaska, 1993.

REMARKS: Diagnostic horizons and features recognized in this soil are: non-saturated organic material filling interstices in fragmental material; assumed cryic temperature regime; pH less than 4.5 (0.01M CaCl2) in all horizons.

Laboratory data for this pedon is available as University of Idaho pedon #80-AK-0202. Laboratory data for another pedon of the Sokolof series is available at the National Soil Survey Lab.

The Sokolof series includes the concept of the tentative Tebenkof series. Tebenkof series should be dropped.

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National Cooperative Soil Survey
U.S.A.