LOCATION GEISERCREEK OR
Established Series
Rev. AEK/RJO/DAL
03/2013
GEISERCREEK SERIES
The Geisercreek series consists of very deep, well drained soils on backslopes to toeslopes of mountains. Geisercreek soils are formed in a mantle of volcanic ash overlying material derived from soft tuffs. Slopes are 0 to 30 percent. The mean annual precipitation is about 25 inches and the mean annual temperature is about 38 degrees F.
TAXONOMIC CLASS: Ashy over clayey, amorphic over smectitic, frigid Alfic Udivitrands
TYPICAL PEDON: Geisercreek ashy silt loam woodland, on a 35 percent west-facing slope at an elevation of 5440 feet. (Colors are for moist soil unless otherwise noted. Textures are apparent field textures.)
Oi--0 to 1 inches; needles and twigs
A--1 to 4 inches; dark brown (10YR 3/3) ashy silt loam, light yellowish brown (10YR 6/4) dry; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many fine and few medium roots; few fine tubular pores; neutral (pH 7.0); clear wavy boundary. (3 to 9 inches thick)
Bw--4 to 11 inches; dark yellowish brown (10YR 4/6) ashy silt loam, very pale brown (10YR 8/4) dry; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine and medium and few coarse roots; few fine tubular pores; slightly acid (pH 6.5); clear smooth boundary. (6 to 12 inches thick)
BC--11 to 16 inches; yellowish brown (10YR 5/6) ashy silt loam, very pale brown (10YR 8/4) dry; weak fine and very fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine and few medium and coarse roots; few fine tubular pores; slightly acid (pH 6.5); abrupt wavy boundary. (5 to 11 inches thick)
2Eb--16 to 25 inches; light olive brown (2.5Y 5/4) cobbly silt loam, light gray (2.5Y 7/2) dry; moderate fine and very fine subangular blocky structure; soft, friable, slightly sticky and slightly plastic; common fine, medium, and coarse roots; common fine and medium tubular pores; 8 percent gravel and 8 percent cobbles; slightly acid (pH 6.5); clear wavy boundary. (0 to 13 inches thick)
2Btb--25 to 36 inches; light olive brown (2.5Y 5/4) silty clay, light yellowish brown (2.5Y 6/4) dry; moderate coarse subangular blocky structure parting to moderate fine and very fine subangular blocky; very hard, firm, moderately sticky and moderately plastic; common fine and medium and few coarse roots; few fine and medium tubular and few fine irregular pores; many distinct clay films on ped faces; 5 percent gravel and 5 percent cobbles; neutral (pH 7.0); gradual smooth boundary. (11 to 34 inches thick)
2BCtb--36 to 46 inches; light olive brown (2.5Y 5/4) silty clay loam, light yellowish brown (2.5Y 6/4) dry; weak fine and medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few fine, medium, and coarse roots; few fine tubular pores; few faint clay films on ped faces; neutral (pH 7.0); gradual smooth boundary. (0 to 25 inches thick)
2C--46 to 62 inches; light olive brown (2.5Y 5/4) silt loam, pale yellow (2.5Y 7/4) dry; weak fine and very fine subangular blocky structure; slightly hard, friable, slightly sticky and moderately plastic; few fine, medium, and coarse roots; neutral (pH 7.0)
TYPE LOCATION: Grant County, Oregon, Section 13, T. 10 S., R. 35 E. (44 degrees, 56 minutes, 18 seconds Latitude, 118 degrees, 23 minutes, 15 seconds Longitude.)
RANGE IN CHARACTERISTICS:
Soil moisture - usually moist but are dry for 30 to 45 consecutive days
Mean annual soil temperature - 39 to 41 degrees F
Mean summer soil temperature - 46 to 49 degrees F
Mean winter soil temperature - 32 to 36 degrees F
Upper part of the particle-size control section - 5 to 15 percent clay (apparent field textures) and 0 to 10 percent rock fragments
Lower part of the particle-size control section - 35 to 45 percent clay and 0 to 30 percent rock fragments (see Remarks)
Depth to bedrock is greater than 60 inches
Depth to the 2Btb is typically 20 to 35 inches
Volcanic ash mantle - 15 to 22 inches thick
Particles of 0.02 to 2.0 mm - 45 to 55 percent
Organic matter - 1 to 5 percent
Acid-oxalate A1 plus 1/2 Fe - 2 to 3 percent
Phosphate retention - 40 to 75 percent
Glass content - 10 to 25 percent
15-bar water retention on air-dried sample - 5 to 15 percent
A horizon
hue - 10YR
Value - 3 or 4 moist, 5 to 7 dry
Chroma - 3 or 4 moist and dry
Texture - ashy SIL
Rock fragments - 0 to 10 percent total with 0 to 10 percent gravel
Clay - 5 to 15 percent
Reaction - 5.6 to 7.3
Bw horizon
hue - 10YR
Value - 3 to 5 moist, 6 to 8 dry
Chroma - 3 to 6 moist and dry
Texture - ashy SIL
Rock fragments - 0 to 10 percent total with 0 to 10 percent gravel
Clay - 5 to 15 percent
Reaction - 5.6 to 7.3
BC horizon
hue - 10YR
Value - 5 or 6 moist, 7 or 8 dry
Chroma - 4 to 6 moist and dry
Texture - ashy SIL
Rock fragments - 0 to 10 percent total with 0 to 10 percent gravel
Clay - 5 to 15 percent
Reaction - 5.6 to 7.3
2Eb horizon
hue - 10YR or 2.5Y
Value - 4 or 5 moist, 6 or 7 dry
Chroma - 2 to 4 moist and dry
Texture - SIL, L, GR-SIL
Rock fragments - 0 to 15 percent total with 0 to 15 percent gravel, 0 to 5 percent cobbles, and 0 to 5 percent stones
Clay - 15 to 25 percent
Reaction - 5.6 to 7.3
2Btb horizon
hue - 10YR, 7.5YR or 2.5Y
Value - 3 to 5 moist, 5 or 6 dry
Chroma - 3 or 4 moist and dry
Texture - SICL, SIC, GR-C, GR-CL, CB-C, CB-SICL, C
Rock fragments - 0 to 30 percent total with 0 to 20 percent gravel, 0 to 10 percent cobbles, and 0 to 5 percent stones
Clay - 35 to 45 percent
Reaction - 5.6 to 7.3
2BCtb horizon
hue - 7.5YR, 10YR or 2.5Y
Value - 4 or 5 moist, 6 or 7 dry
Chroma - 3 or 4 moist and dry
Texture - SICL, SIC, GR-SICL, CB-CL, CB-SICL
Rock fragments - 0 to 30 percent total with 0 to 25 percent gravel, 0 to 15 percent cobbles, and 0 to 5 percent stones
Clay - 30 to 40 percent
Reaction - 5.6 to 7.3
COMPETING SERIES: This is the
Flycreek series.
Flycreek soils - 20 to 40 inches to a lithic contact (tuff)
GEOGRAPHIC SETTING: The Geisercreek soils occur on backslopes to toeslopes of mountains. Elevations are 4,800 to 6,000 feet. Slopes are 0 to 30 percent. Geisercreek soils are formed in a mantle of volcanic ash overlying material derived from soft tuffs. The climate is characterized by cold, wet winters and cool, moist summers. The mean annual precipitation is 20 to 35 inches. The mean annual air temperature is 37 to 44 degrees F. The frost-free period is 30 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Limberjim soils which are on steep side slopes of mountains and are ashy over loamy-skeletal.
DRAINAGE AND PERMEABILITY: Well drained; permeability is moderately rapid in the upper ashy layers and slow in the lower layers.
USE AND VEGETATION: These soils are used for timber production, watershed, wildlife habitat and recreation. The native vegetation is grand fir, western larch, Douglas fir, lodgepole pine, ponderosa pine, grouse whortleberry, bearberry, prince's pine, Oregon grapeholly, twinflower, sidebells pyrola, white flowered hawkweed, woods strawberry, roundleaf violet, lupine, pinegrass, northwestern sedge and elk sedge.
DISTRIBUTION AND EXTENT: MLRA 9. Blue Mountains of northeastern Oregon. The soils are of limited extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Union County, Oregon 1998. The name is from a stream in Baker County.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - from 0 to 3 inches (A horizon)
Cambic horizon - from 3 to 15 inches (Bw and BC horizons)
Argillic horizon - from 24 to 45 inches (2Btb and 2BCtb horizons)
Ash mantle - from 0 to 15 inches
Particle-size control section - from 0 to 40 inches with contrasting classes based on 0 to 15 inches (ashy) and 24 to 40 inches (clayey). This series concept might also have an ashy over loamy class; however, ashy over clayey is the most contrasting
The 2Eb horizon may also be described as a 2Ab, 2Aeb, 2Ebb, 2Bwb, or 2Bw in other areas where this series concept is recognized
The dominant USFS plant association is ABGR/LIB02; others may include ABGR/VASC and ABGR/CARU
National Cooperative Soil Survey
U.S.A.