LOCATION SINONA                  AK

Established Series
Rev. MHC/JPM/DLM
02/2022

SINONA SERIES

Depth class: very deep
Drainage class: somewhat excessively
Parent material: thin mantle of loamy alluvium overlying sandy and gravelly alluvium
Landform: fan terraces on alluvial fans, stream terraces
Slope: 0 to 20 percent
Mean annual temperature: is about 26 degrees F.
Mean annual precipitation: 16 to 40 inches.
Frost free season: 60 to 80 days

TAXONOMIC CLASS: Sandy-skeletal, mixed Typic Haplocryepts

TYPICAL PEDON: Sinona loam on a 0 percent slope under white spruce forest at 2250 feet elevation. (All colors are for moist soil)

Oi--2 inches to 0; dark reddish brown (5YR 3/3) peat; fibrous moss, roots, and twigs; many roots of all sizes; abrupt smooth boundary. (1 to 4 inches thick)

Bw--0 to 3 inches; strong brown (7.5YR 4/6) loam; weak medium subangular blocky structure; very friable, nonsticky and nonplastic; moderately acid (pH 5.6); clear wavy boundary. (1 to 6 inches thick)

BC--3 to 9 inches; olive brown (2.5Y 4/4) stratified sand through silt with composite texture of sandy loam; weak coarse subangular blocky structure; very friable, nonsticky and nonplastic; few very fine roots; moderately acid (pH 5.8); abrupt irregular boundary. (0 to 8 inches thick)

2C--9 to 60 inches; dark brown (10YR 3/3) very cobbly coarse sand; single grain; loose, nonsticky and nonplastic; 35 percent rounded gravel and 20 percent rounded cobble; slightly acid (pH 6.2).

TYPE LOCATION: The Gulkana River Area, Alaska; about 12 miles northwest of Sourdough; the NW1/4 of the NE1/4 of section 32, T.11N., R.2W., Copper River Meridian.

RANGE IN CHARACTERISTICS:
Loamy surface mantle thickness: 2 to 10 inches in thickness over sand and gravel
Solum thickness: 1 to 6 inches
Particle-size size control section: sandy-skeletal with 40 to 70 percent coarse fragments

Oi horizon:
Color: hue of 5YR to 10YR; value of 2 or 2.5; chroma of 1 or 2
Organic matter content65 to 90 percent
Reactionextremely acid to slightly acid

A horizon:
Color: has value of 2 or 3; chroma of 1 to 4
Texture: silt loam, loam, fine sandy loam
Reaction: extremely acid to strongly acid

Bw horizon:
Color: hue of 5YR to YR; value of 3 or 4; chroma of 3 to 6
Texture: loam, sandy loam, fine sandy loam modified by 0 to 20 percent total coarse fragments; 0 to 20 percent rounded gravel, 0 to 20 percent rounded cobble.
Reaction: very strongly acid to slightly acid

2Bw horizon: (where present)
Color: hue of 7.5YR to 2.5Y; value of 4 or 5; chroma of 4 to 6
Texture: sandy loam modified by 35 to 50 total coarse fragments; 10 to 30 percent rounded indurated gravel; 0 to 20 percent rounded indurated cobble
Reaction: very strongly acid to slightly acid

2C horizons:
Color: variegated
Texture: sand, coarse sand, loamy sand modified by 40 to 75 percent total coarse fragments; 20 to 60 percent rounded gravel, 0 to 25 percent rounded cobble.
Reaction: moderately acid to neutral

COMPETING SERIES: These are the Como, Donnelly, and Pippin series. Como soils have continuous E horizons. Donnelly soils have micaceous loess mantles. Pippin soils have loess mantles that are coarse-silty.

GEOGRAPHIC SETTING:
Parent material: thin mantle of loamy alluvium overlying sandy and gravelly alluvium
Landform: fan terraces on alluvial fans, stream terraces
Slope: 0 to 20 percent
Mean annual temperature: is about 26 degrees F.
Mean annual precipitation: 16 to 40 inches.
Frost free season: 60 to 80 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are Maclaren and Nizina soils. Maclaren soils are well drained, very deep, and occur on stream terraces. Nizina soils are somewhat excessively drained, and occur on flood plains.

DRAINAGE AND PERMEABILITY: Well drained, low to high runoff. Saturated hydraulic conductivity is moderately high to high in the loamy surface mantle; very high to high below.

USE AND VEGETATION: Primary use is as wildlife habitat. Vegetation is white and black spruce forest.

DISTRIBUTION AND EXTENT: MLRA 228, Interior Alaska Mountains, South-central Alaska. The series is of small extent.

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

SERIES ESTABLISHED: Gulkana River Area, Alaska, 1999.

REMARKS: Diagnostic features and horizons recognized in this profile include:
Cambic horizon: 0 to 3 inches
Coarse-loamy particle size control section; 0 to 9 inches, loamy stratified alluvium; sandy-skeletal particle size from 9 to 60 inches
Temperature regime: cryic
Formerly classified as Typic Cryochrepts.

This soil has stratified textures and could meet Fluventic subgroup criterion.--DLM

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National Cooperative Soil Survey
U.S.A.