LOCATION VERSTOVIA AK

Established Series
Rev. CSC/JMD/JPM
02/2022

VERSTOVIA SERIES

The Verstovia series consists of shallow to bedrock, well drained soils formed in volcanic ash on mountain slopes and hillslopes. Slopes range from 35 to 120 percent. Mean annual precipitation is in excess of 60 inches, and the mean annual temperature is about 46 degrees F.

TAXONOMIC CLASS: Medial, amorphic Lithic Humicryods

TYPICAL PEDON: Verstovia loam - on a southwest facing linear slope of 75 percent at 400 feet elevation. (All colors are for moist soil, all textures are apparent field textures)

Oe-- 4 to 0 inches; mucky peat; many very fine, fine and medium roots; abrupt wavy boundary. (0 to 4 inches thick)

E-- 0 to 1 inch; gray (N 5/0) loam; weak coarse granular structure; slightly sticky and slightly plastic; strongly smeary; 10 percent gravel; many very fine, fine and medium roots; extremely acid (pH 4.0); abrupt wavy boundary. (1 to 2 inches thick)

Bh-- 1 to 2 inches; black (5YR 2/1) mucky silt loam; moderate medium granular structure; slightly sticky and slightly plastic; strongly smeary; 10 percent gravel; many very fine, fine and medium roots; extremely acid (pH 4.0); abrupt wavy boundary. (0 to 6 inches thick)

Bs1-- 2 to 6 inches; dark reddish brown (2.5YR 3/4) silt loam; moderate medium subangular blocky structure; slightly sticky and slightly plastic; strongly smeary; 10 percent gravel; common very fine, fine and medium roots; very strongly acid (pH 5.0); clear wavy boundary. (3 to 7 inches thick)

Bs2-- 6 to 15 inches; brown (7.5YR 4/4) cobbly silt loam; moderate medium subangular blocky structure; slightly sticky and slightly plastic; strongly smeary; 10 percent gravel and 20 percent cobble; common fine and medium roots; moderately acid (pH 6.0); gradual wavy boundary. (0 to 6 inches thick)

C-- 15 to 19 inches; reddish brown (5YR 4/4) and dark reddish brown (5YR 3/4) cobbly silt loam; massive; slightly sticky and slightly plastic; strongly smeary; 10 percent gravel and 20 percent cobble; few fine roots; moderately acid (pH 6.0); abrupt smooth boundary. (2 to 5 inches thick)

R-- 19 inches; consolidated bedrock

TYPE LOCATION: Suprise Lake, Chatham Area, Alaska. NW1/4, NW1/4, Sec. 12, T.50S., R.62E., Copper River Meridian.

RANGE IN CHARACTERISTICS: Mean annual soil temperature ranges from 38 to 42 degrees F. Thickness of the solum ranges from 10 to 20 inches. Depth to bedrock ranges from 14 to 20 inches. Phosphorous retention is greater than 85 percent. Bulk density is less than 0.90 g/cc. Moist 15 bar water content ranges from 30 to 100 percent. Reaction increases with depth, ranging from extremely acid to slightly acid. Coarse fragment content in the control section ranges from 0 to 30 percent with 0 to 15 percent gravel size pumice and 0 to 30 percent cobble.

An Oi or Oa horizon is present in some pedons. Combined thickness of the O horizons ranges from 2 to 8 inches.

The E horizon has hue of 7.5YR or 10YR, value from 3 to 5 and chroma from 0 to 3. Texture is commonly silt loam but ranges to include loam or sandy loam. The coarse fragment content ranges from 0 to 10 percent gravel size pumice.

The Bh horizon has hue from 2.5YR to 7.5YR, value of 1 or 2, and chroma from 0 to 2. The coarse fragment content ranges from 0 to 10 percent gravel size pumice.

A Bhs is present in some pedons.

The Bs horizons have hue from 2.5YR to 7.5YR; value from 3 to 5, and chroma from 3 to 6. The coarse fragment content ranges from 0 to 30 percent with 0 to 15 percent gravel size pumice and 0 to 30 percent cobble. The C horizon has hue from 5YR to 10YR, value from 3 to 5 and chroma from 2 to 4. Texture is commonly silt loam but ranges to include loam or fine sandy loam. The coarse fragment content ranges from 0 to 30 percent with 0 to 10 percent gravel size pumice and 0 to 30 cobble.

COMPETING SERIES: There are no competing series in the same family.

GEOGRAPHIC SETTING: The Verstovia soils are on mountain slopes and hillslopes and are formed in volcanic ash. The climate is humid maritime with a mean annual precipitation range of 60 to 220 inches. The mean annual temperature is about 46 degrees F. and the mean summer temperature is about 57 degrees F. Elevation ranges from 0 to 3000 feet.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the McGilvery, Partofshikof, Sitka, and Sukoi soils on similar landforms. McGilvery soils are organic and less than 10 inches deep over bedrock. Sitka soils are deeper than 40 inches over bedrock. Partofshikof soils are somewhat poorly drained, are deeper than 40 inches to bedrock and are generally on less steep slopes than Verstovia soils. Sukoi soils are poorly drained and very deep.

DRAINAGE AND PERMEABILITY: Well drained. Moderate permeability. Very slow runoff.

USE AND VEGETATION: The Verstovia soils are used for timber production, watershed protection, wildlife habitat and recreation. The overstory is dominantly western hemlock. The understory is dominantly blueberry.

DISTRIBUTION AND EXTENT: Southeast Alaska. The series is of moderate extent.

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

SERIES ESTABLISHED: Chatham Area, Tongass National Forest, Alaska, 1992.
REMARKS: Diagnostic horizons and features recognized in this soil include: an albic horizon from 0 to 1 inch; a spodic horizon from 1 to 15 inches; assumed organic carbon content greater than 6 percent in the upper 10 cm; Andic soil properties throughout the mineral soil; cryic temperature regime; consolidated bedrock at 19 inches; assumed moist 15 bar water content between 30 and 100 percent.

No lab data is available for this soil. Andic soil properties are assumed based on field morphology and lab data from the associated Sukoi series (NSSL S87AK-220-010).

National Cooperative Soil Survey
U.S.A.