LOCATION ALSPAUGH OREstablished Series
TAXONOMIC CLASS: Fine, mixed, active, mesic Typic Paleudults
TYPICAL PEDON: Alspaugh clay loam - cultivated. (Colors are for moist soil unless otherwise noted.)
Ap--0 to 7 inches; dark brown (7.5YR 3/2) clay loam, brown (10YR 5/3) dry; moderate fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine irregular pores; many fine and medium concretions; medium acid (pH 5.8); abrupt smooth boundary. (6 to 8 inches thick)
AB--7 to 14 inches; dark brown (7.5YR 3/3) clay loam, brown (10YR 5/3) dry; moderate very fine subangular blocky structure; slightly hard, friable, slightly sticky and plastic; common very fine roots; many very fine irregular pores; few fine concretions; medium acid (pH 5.6); clear wavy boundary. (5 to 7 inches thick)
BA--14 to 19 inches; dark brown (7.5YR 4/4) clay, brown (7.5YR 5/4) dry; moderate fine subangular blocky structure; hard, friable, sticky and plastic; common very fine roots; many very fine tubular pores; few fine concretions; strongly acid (pH 5.5); clear wavy boundary. (0 to 7 inches thick)
Bt1--19 to 26 inches; reddish brown (5YR 4/4) clay, reddish brown (5YR 5/4) dry; moderate fine and medium subangular blocky structure; hard, firm, sticky and plastic; common very fine roots; many very fine tubular pores; common moderately thick clay films; few fine concretions; strongly acid (pH 5.5); gradual wavy boundary. (5 to 15 inches thick)
Bt2--26 to 35 inches; reddish brown (5YR 4/4) clay, reddish brown (5YR 5/4) dry; moderate fine and medium subangular blocky structure; hard, firm, sticky and plastic; few fine roots; many very fine tubular pores; common moderately thick clay films; few fine concretions; strongly acid (pH 5.4); gradual wavy boundary. (6 to 15 inches thick)
Bt3--35 to 43 inches; reddish brown (5YR 4/4) clay, reddish brown (5YR 5/4) dry; weak fine and medium subangular blocky structure; hard, firm, sticky and plastic; few fine roots; common very fine tubular pores; few thin clay films; 5 percent fine rock fragments; strongly acid (pH 5.2); clear wavy boundary. (6 to 10 inches thick)
2C--43 to 60 inches; reddish brown (5YR 4/4) very gravelly clay, brown (7.5YR 5/4) dry; massive; very hard, very firm, sticky and plastic; few fine irregular pores in fractures; 30 percent weathered gravel and 30 percent weathered cobbles of andesite and tuff; strongly acid (pH 5.3).
TYPE LOCATION: Clackamas County, Oregon; 5 1/2 miles east of Estacada; 200 feet north of road intersection in the southwest 1/4 southeast 1/4 northeast 1/4, sec. 20, T. 3 S., R. 5 E.
RANGE IN CHARACTERISTICS: The soil is usually moist, but is dry between depths of 4 and 12 inches for a short period of less than 45 consecutive days during the summer. The mean annual soil temperature is 47 to 51 degrees F. The solum is 30 to 60 inches thick. The depth to bedrock commonly is 60 inches or more.
The A horizon has hue of 10YR or 7.5YR, value of 2 or 3 moist, 4 or 5 dry, and chroma of 2 or 3 moist and dry. It has 0 to 15 percent gravel.
The Bt2 horizon has hue commonly of 5YR, but ranges to 7.5YR, value of 3 or 4 moist, and 4 or 5 dry. It is clay loam, clay, or silty clay loam and averages 35 to 45 percent clay. It has 0 to 20 percent gravel and 0 to 10 percent cobbles of weathered andesite or tuff. It is very strongly acid or strongly acid.
The Bt3 horizon has hue of 5YR, 7.5YR, or 10YR, value of 3 or 4 moist, 5 or 6 dry, and chroma of 3 or 4 moist and dry. It is clay loam, clay, or silty clay. It has 0 to 20 percent gravel and 0 to 20 percent
cobbles of weathered andesite or tuff. It is very strongly acid or strongly acid.
The 2C horizon has hue of 5YR, 7.5YR, or 10YR and value of 4 or 5 moist and 5 or 6 dry. It is very gravelly clay loam, or very gravelly clay. It has 30 to 50 percent gravel and 0 to 20 percent cobbles of weathered andesite or tuff. It is very strongly acid or strongly acid.
COMPETING SERIES: There are no other series in this family. Similar soils include the Apt and Honeygrove series. Apt and Honeygrove have 0.9 percent or more organic carbon in the upper 15 centimeters of the argillic horizon.
GEOGRAPHIC SETTING: Alspaugh soils are on high old terraces and hill slopes at elevations of 800 to 1,800 feet. Slopes are 2 to 50 percent. The soils formed in alluvium and colluvium weathered from andesite or tuff. Summers are warm and dry and winters are cool and moist. Mean annual precipitation is 60 to 85 inches, mean annual temperature is 48 to 52 degrees F, mean July temperature is about 67 degrees F, mean January temperature is about 41 degrees F, and the frost-free period is 140 to 200 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aschoff, Bull Run, Cazadero, and Hoodview soils. Aschoff and Hoodview soils are medial-skeletal and lack an argillic horizon. Bull Run soils have silt loam throughout the solum and lack an argillic horizon. Cazadero soils have value of 3 moist and 4 dry throughout the argillic horizon and have 50 to 60 percent clay in the lower part of the subsoil.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderately slow permeability.
USE AND VEGETATION: The soils are used for timber production, hay, pasture, grass seed, and berries. Native vegetation dominantly is Douglas-fir, red alder, salal, brackenfern and western swordfern.
DISTRIBUTION AND EXTENT: Low hills of the Cascade Mountains of northwestern Oregon. The series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Clackamas County, Oregon, 1982.
ADDITIONAL DATA: Characterization data for one pedon (S70 Oreg-3-5) by SCS Riverside Soil Survey Laboratory.