LOCATION HILINE                  AK

Established Series
KMO-JPM
05/2022

HILINE SERIES

The Hiline series consists of very deep, very poorly drained soils formed in alluvium on floodplains and stream terraces. Slopes range from 0 to 2 percent. Mean annual temperature is about 32 degrees F., and the average annual temperature is about 28 inches.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, acid Typic Cryaquents

TYPICAL PEDON: Hiline silt loam - on a slope of 1 percent under shrubby vegetation. (All colors are for moist soil)

Oi -- 2 inches to 0; very dark brown (10YR 2/2) mat of decomposing roots and grasses; very strongly acid; abrupt smooth boundary. (2 to 6 inches thick)

A -- 0 to 3 inches; dark gray (10YR 4/1) silt loam; weak fine granular structure; friable; very strongly acid; clear smooth boundary. (3 to 6 inches thick)

C1 -- 3 to 31 inches; gray (10YR 5/1) fine sandy loam stratified with silt loam and fine sand; massive; friable; common fine distinct strong brown (7.5YR 4/6) mottles; strongly acid; clear smooth boundary. (0 to 30 inches thick)

C2 -- 31 to 41 inches; gray (10YR 5/1) silt loam; massive; friable; common fine distinct strong brown (7.5YR 4/6) mottles; strongly acid; clear smooth boundary. (0 to 35 inches thick)

2C3 -- 41 to 60 inches; grayish brown (10YR 5/2) gravelly sand; single grain; loose; 20 percent gravel, 5 percent cobble; strongly acid.

TYPE LOCATION: Yentna Area, Alaska; SW 1/4, NE 1/4, Section 32, T.25N., R.9W., Seward Meridian.

RANGE IN CHARACTERISTICS: Depth to underlying sandy and gravelly material is more than 40 inches. Coarse fragment content within the control section ranges from 0 to 30 percent with 0 to 20 percent gravel and 0 to 10 percent cobble. Reaction throughout the profile is very strongly acid or strongly acid with pH less than 5.5 (H20, 1:1).

The A horizon has hue of 10YR or 2.5Y; value moist from 3 to 4; and chroma moist of 2 or less. Texture is silt loam stratified with fine sandy loam, sandy loam, and fine sand. Coarse fragment content includes 0 to 5 percent gravel and 0 to 5 percent cobble.

The C horizons have hue from 10YR to 5Y; value moist of 4 or 5, and chroma moist of 1 or 2. Texture is fine sandy loam stratified with silt loam, sandy loam and fine sand. Coarse fragment content ranges from 10 to 30 percent with 10 to 30 percent gravel and 0 to 10 percent cobble. Red and brown mottles are often present along root channels.

The 2C horizon has hue from 10YR to 5Y; value moist of 4 or 5; and chroma moist of 1 or 2. Texture is stratified sand and gravel. Small pockets of finer material and peat may be scattered throught the horizon. Coarse fragment content ranges from 25 to 60 percent, with 15 to 40 percent gravel and 10 to 20 percent cobble.

COMPETING SERIES: This is the Eshamy(T) series in the same family and the Beluga and Moose River series. Eshamy(T) soils have massive, firm substratums. Beluga and Moose River soils have pH greater than 5.5 (H20,1:1) in some part of the control section.

GEOGRAPHIC SETTING: The Hiline soils are on nearly level floodplains and stream terraces. The soils formed in stratified alluvium. Most areas are subject to frequent overflow and many areas are affected by seepage from adjacent areas. The climate is transitional from maritime to continental and is characterized by cool summers and by longmoderately cold winters. Mean annual temperature ranges from 32 to 36 degrees F., and the average annual precipitation ranges from 20 to 38 inches. Slope is less than 2 percent.

DRAINAGE AND PERMEABILITY: Very poorly drained. Slow runoff. Moderate permeability in the surface layers and rapid in the underlying material. The soil is subject to frequent flooding.

USE AND VEGETATION: Sparse stands of white spruce, balsam poplar and alders. Understory includes willows, bluejoint grass and forbs. Used primarily for recreation and wildlife habitat. A few areas are used for hay and pasture.

DISTRIBUTION AND EXTENT: Southcentral Alaska. The series is of moderate extent.

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

SERIES ESTABLISHED: Yentna Area, Alaska, 1986.

REMARKS: Diagnostic horizons and features recognized in this profile include: mottles and chromas of 2 or less from 0 to 41 inches; cryic temperature regime; fine sandy loam and silt loam with less than 18 percent clay from 0 to 41 inches; pH less than 5.5 (H2O,1:1) from 0 to 60 inches.

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National Cooperative Soil Survey
U.S.A.