LOCATION BOULDER POINT           AK

Established Series
Rev. WDB
02/2022

BOULDER POINT SERIES


The Boulder Point series consists of deep, well drained soils formed in eolian material overlying glacial till. Boulder Point soils are on glacial moraines and hills. Slopes range from 3 to 45 percent. The mean annual temperature is about 35 degrees F., and the average annual precipitation is about 20 inches.

TAXONOMIC CLASS: Coarse-silty, mixed, superactive Typic Haplocryods

TYPICAL PEDON: Boulder Point very fine sandy loam - forest (All colors are for moist soil)

Oi--4 to 3 inches; forest litter, with large admixture of grass leaves.

Oe--3 inches to 0; dark reddish brown (5YR 2/2) mat of roots and decomposing organic materials; medium acid; abrupt smooth boundary. (2 to 3 inches thick)

A--0 to 3 inches; black (10YR 2/1) very fine sandy loam; weak fine granular structure; very friable; many roots; strongly acid; clear wavy boundary. (2 to 4 inches thick)

Bhs--3 to 6 inches; dark reddish brown (5YR 2/2) very fine sandy loam; weak fine subangular blocky structure; very friable; many roots; strongly acid; clear wavy boundary. (2 to 4 inches thick)

Bs--6 to 11 inches; dark reddish brown (5YR 3/4) silt loam grading to brown (7.5YR 4/4) in lower part of horizon; weak medium subangular blocky structure; very friable; common roots; strongly acid; clear wavy boundary. (4 to 7 inches thick)

BC1--11 to 17 inches; brown (10YR 4/3) silt loam; weak medium subangular blocky structure; very friable; few roots; fine pores common; strongly acid; gradual boundary

BC2--17 to 25 inches; dark yellowish brown (10YR 4/4) silt loam; weak medium to coarse subangular blocky structure; very friable; few roots; fine pores common; strongly acid; clear wavy boundary.

C1--25 to 31 inches; light olive brown (2.5Y 5/4) silt loam; common medium distinct mottles of strong brown; moderate coarse subangular blocky structure; very friable; few roots; many fine pores; strongly acid; abrupt wavy boundary.

2C2--31 to 40 inches; olive gray (5Y 5/2) stony silt loam; common large distinct mottles of yellowish brown; about 25 percent of horizon consists of subangular stones larger than 3 inches; silt loam fraction is friable; thin lens of gravelly sandy loam at top of horizon; medium acid; many feet thick.

TYPE LOCATION: Kenai-Kasilof Area, Alaska. NW 1/4, NW 1/4, section 2, T.7N., R.12W., Seward Meridian.

RANGE IN CHARACTERISTICS: In places a thin gray horizon occurs between the A1 and B2 horizons. Colors in the upper B horizons range from 5YR 2/2 through 5YR 3/4. The lower B horizons range in color from 7.5YR 4/4 through 10YR 4/3. Texture in the upper 6 to 10 inches of the soil ranges from silt loam to very fine sandy loam; the lower part of the solum is always silt loam. Depth to the stony substratum ranges from 24to mor than 40 inches. COMPETING SERIES: These are the Cohoe, Darling, Kenai, Kroto, Strandline, and Whitsol series in the same family. Cohoe soils have strata of sand and sandy loam in the control section. Darling, Kroto, Strandline and Whitsol soils are not stony in the substratum. Kenai soils have more than 18 percent clay in the substratum.

GEOGRAPHIC SETTING: Boulder Point soils are on hills and moraines bordering the coast. They are formed in windlaid materials derived from tidal areas and beaches, and deposited over hilly glacial till. Mean annual temperature ranges from 33 to 36 degrees F., and the mean annual temperature ranges from 18 to 22 inches.

DRAINAGE AND PERMEABILITY: Well drained. Moderate permeability. Moderate to rapid runoff.

USE AND VEGETATION: Thick cover of alder, devil's club, tall grass, fireweed, and other shrubs and forbs. Most areas have been burned over, but in places cottonwood, white spruce, and paper birch are common. Small areas are used for hay, potatoes, and gardens.

DISTRIBUTION AND EXTENT: Northwestern Kenai Peninsula, Alaska. The series is of minor extent, with about 2000 acres mapped.

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

SERIES ESTABLISHED: Kenai-Kasilof Area, Alaska, 1960.


National Cooperative Soil Survey
U.S.A.