LOCATION HYDABURG                AK

Established Series
Rev:WDL/CSC/JPM
05/2022

HYDABURG SERIES

The Hydaburg series consists of shallow, very poorly drained soils formed in moderately decomposed sedge peat overlying bedrock. Hydaburg soils are alpine soils on backslopes of hills and valley sides. Mean annual temperature is about 45 degrees F and mean annual precipitation is about 120 inches. Slopes range from 5 to 80 percent.

TAXONOMIC CLASS: Dysic, shallow Lithic Cryohemists

TYPICAL PEDON: Hydaburg peat - in a swale on a ridge top. (All colors are for moist soil)

Oi1--1/2 to 0 inches; litter of living sphagnum moss and sedges.

Oi2--0 to 4 inches; dark reddish brown (5YR 3/2) peat (90 percent unrubbed, 80 percent rubbed fiber content); many very fine, common medium roots; extremely acid (pH 3.6); clear smooth boundary. (2 to 5 inches thick)

Oe1--4 to 7 1/2 inches; dark reddish brown (5YR 3/2) mucky peat (60 percent unrubbed, 40 percent rubbed fiber content); very friable; common fine roots; extremely acid (pH 3.8); gradual smooth boundary. (2 to 16 inches thick)

Oe2--7 1/2 to 10 1/2 inches; black (5YR 2/1) mucky peat (60 percent unrubbed, 40 percent rubbed fiber content); very friable; common fine roots; extremely acid (pH 3.8); gradual wavy boundary. (2 to 11 inches thick)

C--10 1/2 to 13 inches; dark grayish brown (2.5Y 4/2) silt loam with black (5YR 2/1) organic stains; friable, nonsticky and nonplastic; common fine roots; extremely acid (pH 3.8); abrupt wavy boundary. (2 to 3 inches thick)

R--13 inches; greywacke sandstone bedrock. TYPE LOCATION: Hollis Area, Alaska. Harris ridge, 1 1/2 miles north west of Harris peak. SE 1/4, S33, T73S, R83E, Copper River Meridian.

RANGE IN CHARACTERISTICS: Mean annual soil temperature ranges from 38 to 42 degrees F. Depth to bedrock ranges from 13 to 20 inches. The surface tier is dominantly hemic, with a thin layer of fibric soil at the surface. The subsurface tier is dominantly hemic. pH is less than 4.5 (0.01M CaCl2) throughout the profile. The soil does not freeze below a depth of 2 inches in most years due to maritime influence.

The C horizon has hue ranging from 5YR to 2.5Y, value moist ranges from 2 to 6, and chroma moist from 1 to 8. The texture is commonly silt loam, but ranges to include very fine sandy loam and loam. Coarse fragment content ranges from 10 to 60 percent.

COMPETING SERIES: There are no known competing series.

GEOGRAPHIC SETTING: Hydaburg soils occur on backslopes of hillslopes and valleysides, and on crests of ridges. Slopes range from 5 to 80 percent. The climate is humid maritime with an average annual precipitation of about 120 inches. Snow remains on the ground from 6 to 8 months of the year. The mean annual air temperature is 45 degrees F. Mean summer soil temperature is below 46 degrees F. Elevation is typically greater than 1800 feet.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Sunnyhay and St. Nicholas soils. Sunnyhay soils are shallow sapric soils over bedrock on ridges. St. Nicholas are poorly drained mineral soils less than 20 inches thick over bedrock, and are on shoulderslopes of mountains.

DRAINAGE AND PERMEABILITY: Very poorly drained. Permeability is rapid in the organic layers and moderately rapid in the mineral horizons. Slow to rapid runoff.

USE AND VEGETATION: Hydaburg soils are used for wildlife habitat, water storage, watershed protection, and recreation. The vegetation is dominantly sedges, with minor amounts of deer cabbage and sphagnum moss.

DISTRIBUTION AND EXTENT: Southeast Alaska. The series is extensive.

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

SERIES ESTABLISHED: Hollis Area, Alaska, 1969.

REMARKS: Diagnostic horizons and features recognized in this pedon include: organic soil material from 0 to 10.5 inches; pH of less than 4.5 (0.01 M CaCl2) in the organic material from 0 to 10.5 inches; a lithic contact at 13 inches; a cryic temperature regime.

---

National Cooperative Soil Survey
U.S.A.