LOCATION BROXSON                 AK

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

BROXSON SERIES

Depth class: Very deep
Drainage class: somewhat poorly drained
Parent material: loamy alluvium over sandy and gravelly alluvium
Landform: floodplains
Slopes: 0 to 2 percent
Mean annual precipitation: about 26 inches
Mean annual temperature: about 25 degrees F.

TAXONOMIC CLASS: Sandy-skeletal, mixed, subgelic Oxyaquic Gelorthents

TYPICAL PEDON: Broxson mucky silt loam -- on a slope of 2 percent under feltleaf will scrub, cool. All colors are for moist soil unless noted)

A/Oe--0 to 4 inches; very dark brown (10YR 2/2) and dark brown (10YR 3/3) mixed silt loam and moderately decomposed plant material; weak medium granular structure; very friable, nonsticky and nonplastic; many very fine, fine, medium and few coarse roots; moderately acid (pH 6.0); clear smooth boundary.

A/C--4 to 8 inches; very dark brown (10YR 2/2) and dark grayish brown (10YR 4/2) stratified fine sand to silt; weak medium subangular blocky structure; very friable, nonsticky and nonplastic; common very fine, fine, and medium roots; moderately acid (pH 6.0); clear smooth boundary.

2C1--8 to 17 inches; dark brown (10YR 3/3) extremely cobbly loamy coarse sand; single grain; loose, nonsticky and nonplastic; common very fine and fine roots; 30 percent gravel, 30 percent cobbles; 2 mm brown (7.5YR 4/4) high chroma redox concentrations (approximately 10 percent of horizon); slightly acid (pH 6.2); gradual smooth boundary.

2C2--17 to 60 inches; variegated extremely cobbly loamy coarse sand; single grain; loose, nonsticky and nonplastic; 30 percent gravel, 30 percent cobbles; slightly acid (pH 6.2); gradual smooth boundary.

TYPE LOCATION: The Delta River Survey Area, Alaska; along the upper Delta River approximately one mile below Juneau Falls; UTM coordinates: Zone 6, Easting 554339, Northing 7006262.

RANGE IN CHARACTERISTICS:
Soil moisture regime: Udic
Mean annual soil temperature: about - 0.1 degrees C.
Mean summer soil temperature: about 2.5 degrees C.
Thickness of organic materials: 0 to 3 inches
Depth to strongly contrasting textural stratification: 1 to 2 inches

A, AC horizon:
Color: hue of 7.5YR, 10YR or 2.5Y; value of 2 or 3; chroma of 1 or 3
Texture: stratified silt loam to sand
Silt content: 15 to 35 percent
Sand content: 60 to 85 percent
Organic matter content: 0 to 2 percent
Rock fragments: 0 to 5 percent rounded very strongly cemented gravel; 0 to 5 percent rounded very strongly cemented cobbles
Reaction: strongly acid to slightly alkaline

2AC, 2C horizon:
Color: hue of variegated or 10YR; value of 2 or 3; chroma of 1 through 3
Texture: extremely cobbly coarse sand; very gravelly loamy sand; extremely gravelly coarse sand
Clay content: 0 to 5 percent
Silt content: 0 to 15 percent
Sand content: 80 to 95 percent
Organic matter content: 0 to 0 percent
Rock fragments: 30 to 60 percent rounded very strongly cemented gravel; 5 to 30 percent rounded very strongly cemented cobbles
Reaction: moderately acid to slightly alkaline

COMPETING SERIES: This is the Belmezok series in the same family. Belmezok soils have a continental climate in the winter and a maritime climate in the summer, resulting in a mean summer soil temperature less than 2 degrees C.

GEOGRAPHIC SETTING:
Parent material: Loamy alluvium over sandy and gravelly alluvium
Landform: Floodplains
Slope: 0 to 2 percent
Mean annual temperature: 23 to 27 degrees F.
Mean annual precipitation: 23 to 28 inches

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Schleyer and Nizina soils. Nizina soils are on similar landforms but have warmer summer soil temperature. Schleyer soils have spodic horizons and occur on fans and terraces.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained, low runoff, saturated hydraulic conductivity is moderately high to high in the loamy alluvium and high to very high in the sandy alluvium.

USE AND VEGETATION: Used for wildlife habitat and recreation. The native vegetation is feltleaf will scrub, cool.

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

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

SERIES ESTABLISHED: The Delta River Area, Alaska, 2005

REMARKS: Diagnostic features and horizons recognized in this profile include:
Diagnostic horizons: none
Temperature regime: cryic with MSST about 2.5 degrees C.
Other: saturated conditions within 100cm but no redox depletions within 50cm
Moisture regime: Udic

ADDITIONAL DATA:

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National Cooperative Soil Survey
U.S.A.