LOCATION KRUBATE AK
Established Series
Rev. JWM/JPM
12/2022
KRUBATE SERIES
The Krubate series consists of very deep, well drained soils that formed in very gravelly glaciofluvial deposits on outwash plains. Slopes range from 5 to 70 percent. Mean annual temperature is about 41 degrees F., and the average annual precipitation is about 60 inches.
TAXONOMIC CLASS: Sandy-skeletal, mixed Typic Humicryods
TYPCIAL PEDON: Krubate extremely stony sandy loam - on a SW facing slope of 7 percent at 300 feet elevation under forest vegetation. (All colors are for moist soil unless otherwise indicated).
Oi-- 1 inch to 0; partially decomposed moss, roots, and leaves. (1 to 7 inches thick).
E--0 to 3 inches; gray (10YR 5/1) extremely stony sandy loam; weak fine granular structure; very friable; nonsticky and nonplastic; common very fine, fine, and medium roots; 5 percent stones, 20 percent gravel; extremely acid (pH 4.2); abrupt smooth boundary. (1 to 4 inches thick).
Bhs1--3 to 5 inches; brown (7.5YR 4/4) very gravelly coarse sandy loam; weak fine subangular blocky structure; friable; nonsticky and nonplastic; common very fine, fine, and medium roots; 5 percent stones, 50 percent gravel; very strongly acid (pH 4.7); clear smooth boundary. (2 to 7 inches thick).
Bhs2--5 to 11 inches; reddish brown (5YR 4/4) very gravelly loamy coarse sand; weak fine subangular blocky structure; friable; nonsticky and nonplastic; 5 percent stones, 50 percent gravel; very strongly acid (pH 4.8); clear smooth boundary. (3 to 7 inches thick).
C1--11 to 16 inches; reddish brown (5YR 4/4) and strong brown (7.5YR 5/6) very gravelly loamy coarse sand; single grain; loose; nonsticky and nonplastic; 5 percent cobbles, 30 percent gravel; strongly acid (pH 5.2); clear smooth boundary. (0 to 50 inches thick).
C2--16 to 24 inches; brown (7.5YR 4/4) and strong brown (7.5YR 4/6) very gravelly loamy coarse sand; massive; firm; nonsticky and nonplastic; 5 percent cobbles, 50 percent gravel; strongly acid (pH 5.4); gradual wavy boundary. (0 to 20 inches thick).
C3--24 to 60 inches; brown (7.5YR 4/2) and dark grayish brown (2.5Y 4/2) very gravelly loamy coarse sand; massive; firm; nonsticky and nonplastic; 5 percent cobbles, 50 percent gravel; strongly acid (pH 5.4).
TYPE LOCATION: Haines Area, Alaska. SW1/4 NW1/4, Section 2, R.59E., T.31S., Copper River Meridian.
RANGE IN CHARACTERISTICS: Combined thickness of the spodic horizons range from 6 to 12 inches. The solum ranges from 7 to 18 inches thick. Stones occupy from 0.1 to 15 percent of the surface. Coarse fragment content in the control section ranges from 35 to 70 percent with 35 to 70 percent gravel and 0 to 15 percent cobble or stones. Texture of the control section is sand, coarse sand, loamy sand, or loamy coarse sand. Tree throw has resulted in mixing and churning of horizons in many profiles. There is more than 6 percent organic carbon in the upper 4 inches of the spodic horizon. Depth to sand and gravel is less than 10 inches. Reaction throughout the profile ranges from extremely acid to slightly acid.
An A horizon is present in some pedons.
The E horizon has hue of 5YR, 7.5YR, 10YR, or 2.5Y, value from 3 through 5 moist, and chroma from 1 through 3 moist. Texture is sandy loam, coarse sandy loam, or silt loam. Coarse fragments range from 0 to 30 percent with 0 to 15 percent stones, 0 to 25 percent gravel.
The Bhs and Bs horizons have hue of 10YR, 7.5YR, 5YR, or 2.5YR, value moist of 2 through 6, and chroma moist of 1 through 4. Textures include coarse sandy loam, loamy coarse sand, coarse sand, loamy sand, or sand.
The C horizon is loamy coarse sand, coarse sand, loamy sand, or sand. The C horizon has firm, massive structure.
COMPETING SERIES: This is the tentative
Serene series. Serene (T) soils have a paralithic contact at 20 to 40 inches.
GEOGRAPHIC SETTING: The Krubate soils occur on outwash plains. They formed in very gravelly glaciofluvial deposits. The climate is humid maritime with the average annual precipitation ranging from 55 to 65 inches. Mean annual temperature ranges from 40 to 43 degrees F. Slopes range from 5 to 70 percent. Elevations range from 0 to 800 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the
Passage,
Kupreanof,
Lutak, and
Tolstoi soils. Passage and Tolstoi soils occur on mountain sideslopes and are moderately deep and shallow over bedrock. Lutak soils occur on alluvial terraces and gravelly moraines adjacent to alluvial plains and contain less than 6 percent organic carbon in the upper 4 inches of the spodic horizon. Kupreanof soils occur on moraines and mountain sideslopes, and have loamy-skeletal substratums.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; permeability is moderate in the surface horizons and moderately rapid in the substratum.
USE AND VEGETATION: The Krubate soils are used for timber production, wildlife habitat and recreation. The native vegetation is dominantly Sitka spruce, western hemlock, and some cottonwood, with an understory of devil's club, Sitka alder, rustyleaf menziesia, and mosses.
DISTRIBUTION AND EXTENT: Southeastern Alaska. The series is of minor extent.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: WASILLA, ALASKA
SERIES ESTABLISHED: Haines Area, Alaska. 1985.
REMARKS: Diagnostic horizons and features recognized in this soil are: (1) a spodic horizon from 3 to 11 inches with more than 6 percent organic carbon in the upper 4 inches. (2) a weighted average of greater than 35 percent coarse fragments and loamy coarse sand texture from 5 to 60 inches. That part of the spodic horizon that meets amorphous requirements does not extend more than 4 inches into the 10 to 40 inch control section. The particle size of the control section has a significant relation to the physical and chemical properties of the soil.
ADDITIONAL DATA: Laboratory data is available on this soil: NSSL Numbers 823281-3287.
National Cooperative Soil Survey
U.S.A.