LOCATION TIKCHIK                 AK

Established Series
SAS/TJR/MPR
02/2022

TIKCHIK SERIES

Landscape--hills
Landform--hillslopes
Slope--0 to 40 percent
Parent material--colluvium
Mean annual precipitation--about 1000 mm
Mean annual air temperature--about -1 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--udic
Soil temperature regime--cryic
Soil moisture subclass--typic

TAXONOMIC CLASS: Loamy-skeletal, isotic Typic Humicryepts

TYPICAL PEDON: Tikchik gravelly silt loam on an east-northeast-facing, concave, linear hillslope, on a slope of 4 percent at an elevation of 288 m (The soil was moist throughout when described on June 29, 2009.)

Oe--0 to 4 cm; moderately decomposed plant material; many fine and common medium and coarse roots; very strongly acid (pH 4.7); clear smooth boundary

A--4 to 25 cm; gravelly silt loam, dark gray (7.5YR 4/1) dry, black (7.5YR 2.5/1) moist; weak fine granular structure; slightly hard, friable, nonsticky and nonplastic; many fine and common medium and coarse roots; 30 percent gravel; very strongly acid (pH 5.0); clear irregular boundary

Bw1--25 to 40 cm; very gravelly silt loam, pale brown (10YR 6/3) dry, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; many fine and common coarse roots; 38 percent gravel; strongly acid (pH 5.4); gradual irregular boundary

Bw2--40 to 65 cm; very gravelly silt loam, light yellowish brown (10YR 6/4) dry, dark yellowish brown (10YR 3/4) moist; weak medium subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; few fine roots; 50 percent gravel; moderately acid (pH 5.6); gradual irregular boundary

C--65 to 180 cm; extremely gravelly silt loam, pale brown (10YR 6/3) dry, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; 80 percent gravel; moderately acid (pH 5.8)

TYPE LOCATION: Dillingham Census Area, Alaska, about 130 km north of the city of Dillingham; latitude 60.2347222 degrees north, longitude 158.4025000 degrees west, datum WGS 84 (coordinates determined with a GPS)

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--0 to 2 degrees C
Soil moisture control section--dry less than 45 consecutive days in June through October

Particle-size control section
*Clay content--2 to 12 percent
*Sand content--15 to 45 percent
*Total rock fragment content--35 to 80 percent
*Sodium fluoride pH--8.4 to 11.6
*Ratio of 1500 kPa water to measured clay--0.6 to 6.0

Oe horizon
Thickness--2 to 15 cm

A horizon
Hue--7.5YR, 10YR
Value--2 to 3 moist, 4 or 5 dry
Chroma--1 or 2 moist
Fine-earth texture--silt loam, silt
Clay content--2 to 12 percent
Reaction--4.8 to 5.6
Total rock fragment content--0 to 30 percent
Gravel content--0 to 30 percent
Channer content--0 to 5 percent
Thickness--18 to 30 cm
Base saturation--0 to 20 percent

Bw1 horizon, or Bs horizon (where present)
Hue--5YR, 7.5YR, 10YR
Value--3 to 4 moist, 6 to 7 dry
Chroma--2 to 4 moist
Clay content--2 to 12 percent
Reaction--4.1 to 6.0
Total rock fragment content--0 to 55 percent
Gravel content--0 to 40 percent
Channer content--0 to 15 percent
Cobble content--0 to 10 percent
Thickness--5 to 60 cm

Bw2 horizon, or Bw horizon (where present)
Hue--5YR, 7.5YR, 10YR
Chroma--2 to 4 moist
Clay content--2 to 12 percent
Reaction--5.4 to 6.6
Total rock fragment content--15 to 55 percent
Gravel content--5 to 50 percent
Channer content--0 to 15 percent
Cobble content--0 to 20 percent
Thickness--5 to 60 cm

C horizon
Hue--10YR, 2.5Y
Value--4 or 5 moist, 6 or 7 dry
Clay content--2 to 12 percent
Reaction--5.4 to 6.5
Total rock fragment content--35 to 80 percent
Gravel content--15 to 80 percent
Channer content--0 to 35 percent
Cobble content--0 to 20 percent
Thickness--more than 35 cm

COMPETING SERIES:
Buchia--umbric epipedon extends the entire profile; no cambic horizon
Bigelow--mean annual soil temperature higher than 4 degrees C
Causewa, Hossick, Mirror, Nagyagat--moderately deep (50 to 100 cm) to lithic bedrock
Crannler--moderately deep (50 to 100 cm) to lithic bedrock; mean annual soil temperature higher than 3 degrees C
Henline--moderately deep (50 to 100 cm) to lithic bedrock; mean annual soil temperature higher than 6 degrees C

GEOGRAPHIC SETTING:
Elevation--25 to 1000 m
Climate--warm, moist summers; cold, moist winters
Mean annual precipitation--581 to 1800 mm
Mean annual air temperature-- -3.7 to 0.9 degrees C
Frost-free period--80 to 135 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Stuyahok--ochric epipedon; hills and glaciated plains
Sharp--deep (100 to 150 cm) to lithic contact; ochric epipedon; hills and mountains
Nishlik--andic soil properties; spodic horizon; ochric epipedon; glaciated plains

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained
Saturated hydraulic conductivity (Ksat)--moderately high or high in the A horizon, moderately high throughout the rest of the profile

USE AND VEGETATION:
Use--wildlife habitat, recreation, subsistence
Potential natural vegetation--Sitka alder, bluejoint grass, arctic starflower, spreading woodfern, claspleaf twistedstalk, horsetails

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

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

SERIES ESTABLISHED: Togiak National Wildlife Refuge-Ahklun Mountains Area, Alaska; 2019

REMARKS:
Diagnostic horizons and other features in this pedon
*Particle-size control section--zone from 29 to 104 cm
*Umbric epipedon--A horizon (more than 1/3 of the thickness from the mineral soil surface to the lower boundary of the cambic horizon)
*Cambic horizon--Bw horizon

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National Cooperative Soil Survey
U.S.A.