LOCATION CIIMAQ                  AK

Established Series
SAS/TJR/SJN
02/2022

CIIMAQ SERIES

The Ciimaq series consists of very shallow, well drained soils formed in volcanic ash over bedrock on hills. Slopes range from 0 to 5 percent. The mean annual precipitation is about 850 millimeters and the mean annual air temperature is about 0.2 degrees C.

TAXONOMIC CLASS: Medial, amorphic Lithic Haplocryands

TYPICAL PEDON: Ciimaq highly organic silt, located on the shoulder of a hill with a slope of 1 percent and elevation of 85 meters; when described on July 21st, 2011 the soil was moist throughout (Colors are for moist soil unless otherwise noted)

Oi--0 to 4 centimeters; slightly decomposed plant material; common fine roots, many medium roots, many coarse roots, and many very fine roots; extremely acid, pH 4.4

AE--4 to 10 centimeters; dark brown (7.5YR 3/2) highly organic silt; 10 percent sand; 81 percent silt; 9 percent clay; weak fine granular structure; friable; common fine roots, common medium roots, common coarse roots, and many very fine roots; 5 percent nonflat 2 to 75 millimeter fragments; extremely acid, pH 3.6; clear smooth boundary

Bhs--10 to 13 centimeters; black (5YR 2.5/1) highly organic medial silt loam; 25 percent sand; 70 percent silt; 5 percent clay; weak coarse subangular blocky structure; friable; common fine roots, common medium roots, and many very fine roots; 2 percent nonflat 76 to 250 millimeter fragments and 10 percent nonflat 2 to 75 millimeter fragments; extremely acid, pH 4.3; clear smooth boundary

Bs--13 to 26 centimeters; dark brown (7.5YR 3/3) medial silt loam; 25 percent sand; 70 percent silt; 5 percent clay; weak fine subangular blocky structure; friable; common fine roots, common medium roots, common coarse roots, and common very fine roots; 2 percent nonflat 76 to 250 millimeter fragments and 5 percent nonflat 2 to 75 millimeter fragments; very strongly acid, pH 5.0; clear smooth boundary

2R--26 centimeters; bedrock

TYPE LOCATION: Dillingham Census Area, Alaska; 1.5 kilometers northwest of the Village of Aleknagik; 59.2861111 degrees north latitude and 158.6447222 degrees west longitude.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 0.5 to 1.7 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 - 22 cm
Thickness of spodic horizon - 16 cm
Thickness of andic soil properties - 16 cm
Depth to lithic contact - 26 cm

All mineral horizons-
Reaction - 3.6 to 5.0
Volcanic glass content - 1 to 21 percent
Ammonium oxalate extractable Al + 1/2 Fe - 0.5 to 3.57
Moist bulk density - 0.65 to 0.85 g/cc

Particle-size control section-
Clay content - 5 to 9 percent
Rock fragments - 5 to 12 percent

Oi horizon
Thickness - 4 cm

AE horizon
Hue - 7.5YR
Value - 3
Chroma - 2
Fine earth texture - Highly organic silt
Clay content - 9 percent
Reaction - 3.6
Rock fragments - 5 percent subangular gravles
Thickness - 6 cm

Bhs horizon
Hue - 5YR or 7.5YR
Value - 2 to 3
Chroma - 1 to 3
Fine earth texture - Medial highly organic silt loam
Clay content - 5 percent
Reaction - 4.3
Rock fragments - 12 percent subangular gravels and cobbles
Thickness - 3 cm

Bs horizon
Hue - 7.5YR
Value - 3
Chroma - 3
Fine earth texture - Medial silt loam
Clay content - 5 percent
Reaction - 5.0
Rock fragments - 7 percent subangular gravels and cobbles
Thickness - 13 cm

R horizon
Thickness - 157 cm

COMPETING SERIES:
Treen - No spodic horizon present

GEOGRAPHIC SETTING:
Parent material - Organic material over coarse-loamy volcanic ash over residuum
Landform - Shoulders of hills
Slope - 0 to 5 percent
Elevation - 30 to 219 meters
Climate - Cool summers; cold winters, August and September are the wettest months
Mean annual precipitation - 777 to 924 mm
Mean annual air temperature - -0.4 to 0.6 degrees C
Frost free duration - 80 to 135 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Damcreek - Very deep, aquic conditions within 60 cm, drainageways on plains
Wearyriver - Very deep, aquic conditions at surface, dips on plains
Snagpoint - Very deep, rises on plains, hills

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: (Ksat)
Drainage class - Well drained
Saturation in normal years - None
Flooding - None
Ponding - None
Ksat - Moderately high in the mineral soil, and moderately low in the bedrock layer

USE AND VEGETATION:
Use - Wildlife habitat and subsistence
Potential natural vegetation - Boreal forest composed of white spruce, paper birch, spirea, grass, and ferns

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 - 4 to 26 cm
Umbric epipedon - AE, Bhs, and Bs horizons
Soil moisture regime - Udic
Andic soil properties - Bhs and Bs horizons
Spodic horizon - Bhs and Bs horizons
Lithic contact - At the upper boundary of the R layer

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National Cooperative Soil Survey
U.S.A.