LOCATION OGIVE                   AK

Established Series
Rev. MHC/DLM
05/2022

OGIVE SERIES

Depth class: very deep
Drainage class: somewhat poorly drained
Landforms: swales on mountains
Parent material: silty eolian deposits over gravelly till
Elevation: 2,365 to 3,773 feet (721 to 1,150 m)
Slope: 8 to 45 percent
Annual precipitation: 23 to 37 inches (596 to 940 mm)
Annual temperature: 25 degrees F (-4 degrees C)
Frost-free period: 50 to 70 days

TAXONOMIC CLASS:

TYPICAL PEDON: Ogive silt loam - on a slope of 28 percent under diamondleaf willow-mixed willow scrub mosaic. (All colors are for moist soil)

Oi--0 to 2 inches (0 to 5 cm); dark reddish brown (5YR 2.5/2) slightly decomposed plant material; many very fine, fine, medium, and coarse roots; very strongly acid (pH 5.0); clear smooth boundary.

A1--2 to 6 inches (5 to 15 cm); dark reddish brown (5YR 2.5/2) silt loam; weak medium granular structure; very friable, nonsticky and nonplastic; many very fine, fine, medium, and coarse roots; very strongly acid (pH 4.8); gradual wavy boundary.

A2--6 to 10 inches (15 to 25 cm); dark brown (10YR 3/3) and dark reddish brown (5YR 2.5/2) silt loam; weak medium granular structure; very friable, nonsticky and nonplastic; common very fine, fine, and few medium roots; strongly acid (pH 5.1); clear wavy boundary.

2Bw--10 to 26 inches (25 to 66 cm; dark yellowish brown (10YR 4/4) very cobbly loam; weak coarse subangular blocky structure; friable, nonsticky and nonplastic; few very fine and fine roots; 20 percent gravel, 20 percent cobbles; strongly acid (pH 5.2); gradual smooth boundary.

2C--26 to 60 inches (66 to 152 cm); dark grayish brown (10YR 4/2) very cobbly loam; massive; friable, nonsticky and nonplastic; 20 percent gravel, 20 percent cobbles; moderately acid (pH 5.9).

TYPE LOCATION: Delta River Area, Alaska; along the upper Delta River approximately two miles below Juneau Falls; UTM coordinates: Zone 6, Easting 555935, Northing 7007142.

RANGE IN CHARACTERISTICS:

Soil moisture class: udic
Average annual soil temperature: 32 to 29 degrees F (-0.1 to -1.5 degrees C)
Mean summer soil temperature: 36 to 39 degrees F. (2 to 4 degrees C)
Depth to strongly contrasting textural stratification: 6 to 17 inches (15 to 43 cm)

Oi horizon:
Colorhue of 2.5YR to 10YR; value of 2 to 3; chroma of 1 or 2
Organic matter content65 to 90 percent
Reactionvery strongly acid to moderately acid

A horizon:
Colorhue of 2.5YR to 10YR; value of 2 to 3; chroma of 1 to 3
Texturemucky silt loam; silt loam
Clay content0 to 10 percent
Silt content55 to 75 percent
Sand content15 to 35 percent
Organic matter content6 to 12 percent
Rock fragments0 to 5 percent subangular strongly cemented gravel
Reactionvery strongly acid to moderately acid

2Bhs or 2Bw horizons:
Colorhue of 10R to 10YR; value of 3 to 5; chroma of 2 to 4
Textureextremely cobbly loam; very gravelly loam; extremely cobbly sandy loam
Clay content0 to 10 percent
Silt content15 to 50 percent
Sand content45 to 75 percent
Organic matter content0 to 0 percent
Rock fragments15 to 40 percent subangular strongly cemented gravel; 5 to 30 percent subangular strongly cemented cobbles
Reactionstrongly acid to slightly acid

2C horizon:
Colorhue of 10YR or 2.5Y; value of 3 to 5; chroma of 2 to 4
Texturevery cobbly loam; very gravelly loam; very gravelly sandy loam
Clay content0 to 10 percent
Silt content15 to 50 percent
Sand content45 to 75 percent
Organic matter content0 to 0 percent
Rock fragments15 to 30 percent subangular strongly cemented gravel; 5 to 20 percent subangular strongly cemented cobbles
Reactionstrongly acid to slightly acid

COMPETING SERIES: There are no competing series in this classification.

GEOGRAPHIC SETTING:
Landforms: swales on mountains
Parent material: silty eolian deposits over gravelly till
Elevation: 2,365 to 3,773 feet (721 to 1,150 m)
Slope: 8 to 45 percent
Annual precipitation: 23 to 37 inches (596 to 940 mm)
Annual temperature: 25 degrees F (-4 degrees C)
Frost-free period: 50 to 70 days

GEOGRAPHICALLY ASSOCIATED SOILS: These include Frostcircle and Waitabit soils. Frostcircle soils are poorly drained, shallow or very shallow to permafrost, and occur on mountains. Waitabit soils are well drained, very deep, and occur on mountains.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained, very high runoff. Saturated hydraulic conductivity is moderately high to high.

USE AND VEGETATION: Used for wildlife habitat and recreation. Native vegetation is small.

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: Delta River Area, Alaska, 2005

REMARKS: Diagnostic features and horizons recognized in this profile include:
Umbric epipedon: 2 to 10 inches. (A1 and A2 horizons)
Cambic horizon: 10 to 26 inches. (2Bw horizon)
Lithologic discontinuity: At the upper boundary of 2Bw horizon
Loamy-skeletal particle size control section: 10 to 40 inches below the mineral soil surface
Temperature regime: cryic

ADDITIONAL DATA:

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National Cooperative Soil Survey
U.S.A.