LOCATION KEEFER                  AK

Established Series
SAS/TJR/SJN
05/2022

KEEFER SERIES

The Keefer series consists of very deep, moderately well drained soils formed in loamy alluvium on flood plains. Slopes are 0 to 3 percent. The mean annual precipitation is about 630 millimeters and the mean annual air temperature is about 0.6 degrees C.

TAXONOMIC CLASS: Coarse-loamy, isotic Fluventic Humicryepts

TYPICAL PEDON: Keefer stratified silt loam, located on a flood plain with a slope of 1 percent and elevation of 49 meters; when described on July 3rd, 2009 the soil was wet from 120 to 183 cm (Colors are for moist soil unless otherwise noted)

Oi--0 to 10 cm; slightly decomposed plant material; many very fine and fine roots, common medium roots, and common coarse roots; moderately acid (pH 5.7)

A--10 to 19 cm; very dark brown (10YR 2/2) stratified silt loam; 40 percent sand; 53 percent silt; 7 percent clay; weak medium subangular blocky structure; very friable, nonsticky, nonplastic; common fine and very fine roots, common medium roots, and common coarse roots; extremely acid (pH 4.4)

AB--19 to 100 cm; 60 percent very dark grayish brown (10YR 3/2) stratified fine sandy loam; 60 percent sand; 37 percent silt; 3 percent clay; weak coarse subangular blocky structure; very friable, nonsticky, nonplastic; common fine and very fine roots and common medium roots; 40 percent medium dark reddish brown (5YR 3/4) masses of oxidized iron with clear boundaries; strongly acid (pH 5.2)

Cg--100 to 183 cm; dark gray (10YR 4/1) stratified fine sandy loam; 55 percent sand; 43 percent silt; 2 percent clay; massive; friable, nonsticky, nonplastic; moderately acid (pH 5.6)

TYPE LOCATION: Dillingham Census Area, Alaska; 1 kilometer east southeast of the Village of Koliganek; 59.7238889 degrees north latitude and 157.30083333 degrees west longitude.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 0.9 to 2.5 degrees C (cryic soil temperature regime)
Soil moisture control section - Dry less than 45 consecutive days from June to October (udic soil moisture regime)
Thickness of umbric epipedon - 21 to 90 cm
Depth to redox concentrations - 19 to 58 cm
Depth to aquic conditions - 100 to 180 cm
Depth to reduced matrix - 100 to 180 cm

All mineral horizons-
Reaction - 4.4 to 6.0

Particle-size control section-
Clay content - 0 to 5 percent
Rock fragments - 0 to 50 percent

Oi horizon
Thickness - 10 to 21 cm
Reaction - 5.7 to 6.6

A (or A1) horizon
Hue - 10YR
Value - 3 or 4
Chroma - 1 or 2
Fine earth texture - Very fine sandy loam or stratified silt loam
Clay content - 5 to 9 percent
Reaction - 4.4 to 5.9
Rock fragments - 0 percent
Thickness - 9 to 37 cm

AB (or A2, A3, or A4) horizon
Hue - 7.5YR to 2.5Y
Value - 3 or 4
Chroma - 1 to 4
Fine earth texture - Stratified silt loam, stratified fine sandy loam, or very fine sandy loam
Clay content - 2 to 5 percent
Reaction - 5.2 to 6.0
Rock fragments - 0 to 5 percent coarse and medium gravels
Thickness - 80 to 81 cm

Cg horizon
Hue - 10YR
Value - 4
Chroma - 1
Fine earth texture - Stratified fine sandy loam or fine sand
Clay content - 0 to 5 percent
Reaction - 5.6 to 5.7
Rock fragments - 0 to 50 percent total; 0 to 48 percent medium and coarse gravels, and 0 to 2 percent fine gravels
Thickness - 3 to 83 cm

COMPETING SERIES: There are no competing series

GEOGRAPHIC SETTING:
Parent material - Grassy organic material over coarse-loamy alluvium
Landform - Flood plains
Slope - 0 to 1 percent
Elevation - 7 to 62 meters
Climate - Cool summers; cold winters, August and September are the wettest months
Mean annual precipitation - 609 to 648 mm
Mean annual air temperature - 0.5 to 0.7 degrees C
Frost free duration - 85 to 140 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Lewispoint - Moderately well drained; loamy alluvium; similar landform position
Ekwok - Well drained, loamy eolian deposits, plains
Tunravik - Well drained, eolian and alluvium, terraces

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: (Ksat)
Drainage class - Moderately well drained
Saturation in normal years - Occurs in a layer from 75 to 152 cm of the soil surface for more than two weeks during the growing season
Flooding - Occasional and brief
Ponding - None
Ksat - Moderately high to high throughout the mineral soil material, except high in the C horizon
Redoximorphic features in the upper part of the AB are a result of spring thaw conditions where water perches on top of hard frost.

USE AND VEGETATION:
Use - Wildlife habitat
Potential natural vegetation - Boreal woodland composed of white spruce with an understory of tealeaf willow, arctic raspberry, bluejoint grass, field horsetail, and Canadian burnet

DISTRIBUTION AND EXTENT: Bristol Bay Lowlands; MLRA 236; small extent

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

SERIES ESTABLISHED: Nushagak-Mulchatna Watershed Soil Survey, Dillingham Census Area, Alaska, 2019

REMARKS:
Particle-size control section - 35 to 110 cm
Soil moisture regime - Udic
Umbric epipedon - A and AB horizons
Reduced matrix - Cg horizon
Aquic conditions - Cg horizon
Redox concentrations - AB horizon

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National Cooperative Soil Survey
U.S.A.