LOCATION SHANAHAN OR
Established Series
Rev. JSC/AON/TDT
06/2011
SHANAHAN SERIES
The Shanahan series consists of very deep, somewhat excessively drained soils that formed in ash over buried loamy soils. Shanahan soils are on pumice mantled terraces, ridges, cinder cones, benches, lava plains and lava plateaus. Slopes are 0 to 45 percent. The mean annual precipitation is about 25 inches and the mean annual temperature is about 43 degrees F.
TAXONOMIC CLASS: Ashy over loamy, glassy over isotic Xeric Vitricryands
TYPICAL PEDON: Shanahan paragravelly ashy loamy coarse sand, woodland. (Colors are for moist soil unless otherwise noted.)
A--0 to 4 inches; very dark grayish brown (10YR 3/2) paragravelly ashy loamy coarse sand, grayish brown (10YR 5/2) dry; weak very fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine roots; many very fine pores; 15 percent pumice 2 to 4 millimeters in diameter; slightly acid (pH 6.3); clear wavy boundary. (1 to 9 inches thick)
Bw1--4 to 8 inches; dark brown (10YR 3/3) paragravelly ashy coarse sand, pale brown (10YR 6/3) dry; single grain; soft, very friable, nonsticky and nonplastic; many very fine roots; many very fine pores; about 15 percent pumice 2 to 5 millimeters in diameter; slightly acid (pH 6.4); clear wavy boundary. (0 to 8 inches thick)
Bw2--8 to 15 inches; brown (10YR 4/3) paragravelly ashy coarse sand, yellow (10YR 8/6) dry; single grain; soft, very friable, nonsticky and nonplastic; many very fine and few fine roots; many very fine pores; about 15 percent pumice 2 to 10 millimeters in diameter; slightly acid (pH 6.5); clear wavy boundary. (0 to 15 inches thick)
C--15 to 26 inches; light olive brown (2.5Y 5/4) and light yellowish brown (2.5Y 6/4) ashy coarse sand, pale yellow (2.5Y 7/4) dry; single grain; soft, very friable, nonsticky and nonplastic; many very fine and few fine roots; many very fine pores; 5 percent pumice 2 to 10 millimeters in diameter; many dark brown patches mixed from horizons above and below; slightly acid (pH 6.5); clear wavy boundary. (5 to 29 inches thick)
2Bwb1--26 to 34 inches; brown (7.5YR 4/4) fine sandy loam, brown (7.5YR 5/4) dry; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; few roots; many very fine pores; 10 percent hard lava gravel and cobbles; neutral (pH 6.6); abrupt wavy boundary. (4 to 12 inches thick)
2Bwb2--34 to 45 inches; brown (7.5YR 4/4) fine sandy loam, brown (7.5YR 5/4) massive; soft, very friable, nonsticky and nonplastic; few roots; many very fine pores; 5 percent hard lava gravel; neutral (pH 6.6); abrupt wavy boundary. (5 to 22 inches thick)
2BC--45 to 60 inches; brown (7.5YR 4/4) extremely cobbly fine sandy loam, brown (7.5YR 5/4) dry; massive; soft, very friable, nonsticky and nonplastic; few roots; many very fine pores; about 70 percent cobbles and gravel; neutral (pH 6.6).
TYPE LOCATION: Klamath County, Oregon; about 1 mile northwest of Collier State Park; 1,800 feet west and 700 feet north of the southeast corner section 4, T. 34 S., R. 7 E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 42 to 45 degrees F., and the mean summer soil temperature without an O horizon is 52 to 59 degrees F. and with an O horizon is 40 to 47 degrees F., and the mean winter soil temperature is 32 to 35 degrees F. The soils are dry for 45 to 60 consecutive days when the soil temperature is above 41 degrees F. Depth to bedrock is more than 60 inches. Depth to the buried loamy soil (2Bwb) is 14 to 40 inches. The ash and pumice are dacitic. Pumice size gravel fragments are 2 to 15 millimeters in diameter and predominantly are less than 8 millimeters in diameter. The ash mantle and upper part of the particle-size control section averages 5 to 35 percent paragravelly pumice fragments, 70 to 100 percent glass and glass-coated aggregates, phosphate retention of 25 to 50 percent, acid oxalate extractable aluminum plus one-half the acid oxalate iron of 0.4 to 0.9 percent, 15 bar water content of 4 to 7 percent on both dried and undried samples and moist bulk density of 0.70 to 1.00 grams per cubic centimeter. The ash mantle has field estimated clay content of 0 to 5 percent and the buried loamy material has field estimated clay content of 10 to 20 percent.
Some pedons have an O horizon up to 3 inches thick.
The A horizon has value of 2 to 4 moist, 4 through 7 dry, and chroma of 2 to 4 moist, 1 through 3 dry. It is paragravelly ashy loamy coarse sand or ashy loamy coarse sand. It is slightly acid or neutral.
The Bw horizon when present, has value of 3 to 5 moist, 5 or 6 dry, and chroma of 2 to 6 moist, 1 to 4 dry. It is ashy loamy coarse sand, ashy coarse sand or paragravelly ashy loamy coarse sand. It is slightly acid or neutral.
The C horizon has hue of 10YR through 5Y, value of 3 to 8 moist, 6 to 8 dry, and chroma of 1 to 6 moist and 1 to 4 dry. Basaltic sand grains have value of 2 moist or dry. It is ashy coarse sand or ashy loamy coarse sand with 0 to 55 percent paragravelly pumice fragments. It is slightly acid or neutral.
The 2B horizon has hue of 10YR to 5YR, value of 3 or 4 moist, 5 to 7 dry, and chroma of 2 to 4 moist and 1 to 4 dry. It is loam, sandy loam, gravelly sandy loam, or fine sandy loam and has field-estimated clay of about 10 to 20 percent.
Some pedons below a depth of 40 inches have a 3C horizon comprised of stratified black sands and gravel.
COMPETING SERIES: These are the
Almac,
Codylake,
Gahee,
Helter,
Nile and
Spexarth series. Almac soils have E and Bs horizons and are 40 to 60 inches deep to schist or gneiss. Codylake soils have a granodiorite paralithic contact at 40 to 60 inches and have a loam, sandy loam, or silt loam ash mantle. Helter soils have a silt loam ash mantle. Gahee soils have albic and cambic diagnostic horizons in the upper part of the profile. Nile soils lack pararock fragments. Spexarth soils are moderately deep to a paralithic contact.
GEOGRAPHIC SETTING: Shanahan soils are on pumice mantled ridges, cinder cones, benches, lava plains, lava plateaus and terraces. Slopes are 0 to 45 percent. Elevations range from 4,000 to 6,000 feet. The soils formed in moderately thick, air-laid mantles of dacitic pumiceous ash over buried loamy soils. The climate is subhumid with cool dry summers and cold winters with much snow. The mean annual precipitation is 15 to 41 inches. The mean January temperature is 25 to 27 degrees F., the mean July temperature is 59 to 62 degrees F., and the mean annual temperature is 37 to 45 degrees F. The frost-free period is 0 to 50 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Lapine,
Shukash,
Steiger and
Tutni soils. Lapine soils are ashy-pumiceous. Shukash soils are ashy over loamy-skeletal. Steiger soils are ashy and have the buried loamy soil material at 40 to over 60 inches. Tutni soils lack buried loamy horizons and have redox features at depths of 14 to 20 inches.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; permeability is rapid in the ash mantle and moderately rapid in the buried loamy material.
USE AND VEGETATION: The soils are used for timber, wildlife habitat, recreation, and grazing by livestock. Vegetation mainly is ponderosa pine, antelope bitterbrush, lodgepole pine, western needlegrass, bottlebrush squirreltail, and snowbrush ceanothus.
DISTRIBUTION AND EXTENT: Central and south-central Oregon; MLRA 6. The series is extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Klamath County, Oregon, 1977.
REMARKS: Diagnostic horizons and other features:
Ochric epipedon - Color is strongly contrasting within the fine earth fraction. Soil material less than 0.5 millimeters in size has mollic colors and material greater than or equal to 0.5 millimeters in size has bright colors or high values and high chroma.
Andic soil properties - the ash mantle is the same as for the associated Steiger Series. Data for andic soil properties is from S87OR-035-001 (Steiger Series).
Ash deposit is from Mt. Mazama
ADDITIONAL DATA: Characterization data on 2 profiles (S72 Oreg. 18-1, 18-2) reported in Riverside Soil Survey Laboratory report for Shanahan soils sampled in Klamath County, Oregon, 1972.
National Cooperative Soil Survey
U.S.A.