LOCATION NIKLASON AK

Established Series
Rev. MHC/DM
10/2001
NIKLASON SERIES

The Niklason series consists of very deep, well drained or moderately well drained soils formed in stratified loamy alluvium overlying very gravelly sand. Niklason soils are on stream terraces, flood plains and alluvial fans. Slopes range from 0 to 15 percent. The mean annual temperature is about 34 degrees F., and the average annual precipitation is about 25 inches.

TAXONOMIC CLASS: Coarse-loamy over sandy or sandy-skeletal, mixed, superactive, nonacid Typic Cryofluvents

TYPICAL PEDON: Niklason silt loam - on a level slope under balsam poplar forest at 350 feet elevation. (All colors are for moist soil)

Oe-0 to 2 inches; very dark brown (10YR 2/2) moderately decomposed plant material; many fine roots; abrupt smooth boundary. (1 to 3 inches thick)

A--2 to 6 inches; very dark grayish brown (10YR 3/2) silt loam; weak coarse granular structure; very friable; many roots of all sizes; strongly acid (pH 5.4); clear smooth boundary. (1 to 4 inches thick)

C1--6 to 15 inches; very dark grayish brown (2.5Y 3/2) and dark grayish brown (2.5Y 4/2) stratified fine sand and sand; single grain; loose; few very fine, fine and medium roots; strongly acid (pH 5.4); clear smooth boundary. (3 to 15 inches thick)

C2--15 to 23 inches; very dark grayish brown (2.5Y 3/2) and dark grayish brown (2.5Y 4/2) stratified sand through silt; massive; very friable, nonsticky and nonplastic; few very fine roots; moderately acid (pH 5.6); clear smooth boundary. (4 to 20 inches thick)

2C3--23 to 60 inches; variegated extremely gravelly coarse sand; single grain; loose, nonsticky and nonplastic; 50 percent rounded gravel and 10 percent rounded cobble; moderately acid (pH 5.8).

TYPE LOCATION: Matanuska-Susitna Valley Area, Alaska; in the NW1/4 of the NE1/4 of section 27, T.26N., R.5W., Seward Meridian.

RANGE IN CHARACTERISTICS: Mean annual soil temperature is about 35 degrees F. Depth to very gravelly sand ranges from 14 to 40 inches. After mixing, the upper part of the control section is coarse-loamy. Most pedons have pockets and lenses of buried organic matter at varying depths. Reaction is very strongly acid to moderately acid in the surface horizons and to strongly acid to slightly acid in the underlying horizons.

The A horizon (where present)has hue of 7.5YR to 2.5Y, value of 3 or 4 and chroma of 1 to 4. Texture is silt loam, very fine sandy loam, or fine sandy loam.

The C horizons have hue of 10YR to 5Y, value of 3 to 6, and chroma of 1 to 3. Texture is stratified silt loam, very fine sandy loam, sandy loam, loam, very fine sand, fine sand, sand, and loamy sand.

The 2C horizon is variegated. Texture is sand, loamy sand, or loamy coarse sand modified by 40 to 70 percent coarse fragments, 30 to 65 percent gravel, 10 to 25 percent cobble, and 0 to 3 percent stones.

COMPETING SERIES: These are the Klutina and Tonowek series. Klutina soils have free carbonates in the underlying material. Tonowek soils have a mean annual soil temperature greater than 40 degrees F.

GEOGRAPHIC SETTING: The Niklason soils are on stream terraces, alluvial fans and flood plains. Slopes range from 0 to 15 percent. The soils formed in stratified loamy alluvium overlying very gravelly sand. The mean annual temperature ranges from 30 to 36 degrees F. Average annual precipitation ranges from 14 to 30 inches.

GEOGRAPHICALLY ASSOCIATED SOILS:

DRAINAGE AND PERMEABILITY: Well drained or moderately well drained. Slow runoff. Moderate permeability in the coarse loamy upper horizons and rapid in the gravelly underlying material. Niklason soils are subject to occasional and frequent flooding.

USE AND VEGETATION: Mostly forested. Dominant trees are paper birch, white spruce, and cottonwood. Cleared areas are used for cropland and pasture. The principal crops are oats, barley, bromegrass, potatoes, and hardy vegetables.

DISTRIBUTION AND EXTENT: Cook Inlet-Susitna Lowlands, South-central Alaska. The series is of moderate extent.

MLRA OFFICE RESPONSIBLE: Anchorage, Alaska

SERIES ESTABLISHED: Matanuska Valley Area, Alaska, 1966.

REMARKS: Diagnostic features recognized in this profile include: no diagnostic horizons; assumed irregular decrease in organic carbon based on colors, stratification, and occasional flooding; cryic temperature regime; coarse loamy particle size (weighted average) from 2 to 23 inches, sandy or sandy-skeletal from 23 to 60 inches; pH greater than 5.5 from 15 to 60 inches.

National Cooperative Soil Survey
U.S.A.

Contact: Mike Gracz Kenai Watershed Forum  PO Box 15301 Fritz Creek, AK  99603 907-235-2218

04 May 2007 10:23