LOCATION BARLOW OREstablished Series
TAXONOMIC CLASS: Coarse-loamy, isotic Typic Haplocryods
TYPICAL PEDON: Barlow silt loam, forested. (Colors are for moist soil unless otherwise noted.)
O1--6 to 5 inches; needles, twigs, cones, etc.
O2--5 inches to 0; very dark gray (10YR 3/1) and very dark brown (10YR 2/2) amorphous organic matter; many roots; abrupt wavy boundary. (3 to 8 inches thick)
A2--0 to 1 1/2 inches; dark gray (10YR 4/1) silt loam, light gray to gray (10YR 6/1) dry; massive; soft, very friable, nonsticky and nonplastic; many roots; many very fine and fine irregular pores; very strongly acid (pH 4.7); abrupt wavy boundary. (1/2 to 3 inches thick)
B2ir--1 1/2 to 9 inches; dark yellowish brown (10YR 3/4) silt loam, brown (10YR 5/3) dry and crushed; variegated with brown (7.5YR 4/2 and 4/4 and 10YR 4/3) and dark grayish brown (10YR 4/2); massive; slightly hard, friable, nonsticky and slightly plastic; many roots; many very fine and fine irregular pores; strongly acid (pH 5.1); gradual wavy boundary. (4 to 15 inches thick)
B3--9 to 20 inches; dark grayish brown (10YR 4/4) stony fine sandy loam, brown (10YR 5/3) dry and crushed; variegated with 20 percent dark brown (7.5YR 3/2); massive; soft, very friable, nonsticky and slightly plastic; 15 percent stones, 10 percent cobbles, and 10 percent pebbles; many roots; many very fine and fine irregular pores; strongly acid (pH 5.4). Many feet thick.
IIC--20 to 40 inches; dark yellowish brown (10YR 4/4) stony fine sandy loam, brown (10YR 5/3) dry and crushed; variegated with 20 percent dark brown (7.5YR 3/2); massive; soft, very friable, nonsticky and slightly plastic; 15 percent stones, 10 percent cobbles, and 10 percent pebbles; many roots; many very fine and fine irregular pores; strongly acid (pH 5.4). Many feet thick.
TYPE LOCATION: Clackamas County, Oregon; 200 feet west of the Timberline Highway; NE1/4 NE1/4 section 18, T.3S., R.9E. W.M.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 40 degrees to 47 degrees F. The average summer soil temperature is less than 47 degrees F. with an 0 horizon. The soils have an udic moisture regime. The driest period is in the summer but the soils are dry for less than 45 consecutive days. Depth to bedrock is 60 inches or more. Depth to stony glacial till ranges from 15 to 30 inches. Thickness of the solum ranges from 15 to 24 inches. The 10- to 40-inch control section has less than an average of 10 percent clay and has 20 to 30 percent sand coarser than very fine sand.
The A2 horizon has value of 4 or 5 moist, 6 or 7 dry, and chroma of 1 or 2 moist and dry. It is silt loam or very fine sandy loam.
The B2ir horizon has hue of 10YR through 5YR, value of 3 or 4 moist, 5 or 6 dry, and chroma of 2 through 6. The colors are commonly variegated. This horizon is silt loam or very fine sandy loam. It ranges from slightly hard to hard and from friable to firm.
The B3 horizon has chroma of 2 or 3 moist and dry. It is silt loam or very fine sandy loam.
The IIC horizon has hue of 10YR or 7.5YR, value of 3 or 4 moist and 5 or 6 dry, and chroma of 2 through 4 moist and dry. It is fine sandy loam or sandy loam. It has very friable to firm and soft to hard consistence. Rock fragments range from 20 to 40 percent to depth of 40 inches. Below depth of 40 inches they range from 60 percent in some pedons. Stone size fragments are commonly dominant.
TYPE LOCATION: Clackamas County, Oregon; 200 feet west of the Timberline Highway; NE1/4 NE1/4 section 18, T.3S., R.9E. W.M.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 40 degrees to 47 degrees F. The average summer soil temperature is less than 47 degrees F. with an 0 horizon. The soils have an udic moisture regime. The driest period is in the summer but the soils are dry for less than 45 consecutive days. Depth to bedrock is 60 inches or more. Depth to stony glacial till ranges from 15 to 30 inches. Thickness of the solum ranges from 15 to 24 inches. The 10- to 40-inch control section has less than an average of 10 percent clay and has 20 to 30 percent sand coarser than very fine sand.
The A2 horizon has value of 4 or 5 moist, 6 or 7 dry, and chroma of 1 or 2 moist and dry. It is silt loam or very fine sandy loam.
The B2ir horizon has hue of 10YR through 5YR, value of 3 or 4 moist, 5 or 6 dry, and chroma of 2 through 6. The colors are commonly variegated. This horizon is silt loam or very fine sandy loam. It ranges from slightly hard to hard and from friable to firm.
The B3 horizon has chroma of 2 or 3 moist and dry. It is silt loam or very fine sandy loam.
The IIC horizon has hue of 10YR or 7.5YR, value of 3 or 4 moist and 5 or 6 dry, and chroma of 2 through 4 moist and dry. It is fine sandy loam or sandy loam. It has very friable to firm and soft to hard consistence. Rock fragments range from 20 to 40 percent to depth of 40 inches. Below depth of 40 inches they they range from 60 percent in some pedons. Stone size fragments are commonly dominant.
COMPETING SERIES: These are the Blossom, Naptowne, and Timberly series. Blossom soils are 20 to 40 inches deep to gneiss bedrock. Naptowne soils have sola less than 13 inches thick, have hue of 2.5Y or 5Y in the C horizon and are in an area that receives 18 to 25 inches of precipitation. Timberly soils have A1 and A2 horizons 8 to 15 inches thick and have soil temperature ranging from 35 degrees to 40 degrees F.
GEOGRAPHIC SETTING: The Barlow soils are on ridgetops and hill slopes in high mountainous areas at elevations of 4,000 to 6,000 feet. Slopes range from 5 to 60 percent. The soils formed in loess or eolian deposits and moderately coarse textured glacial till of andesitic and basaltic origin. The climate is humid and cold. The mean annual precipitation ranges from 100 to 120 inches. The mean annual temperature is 38 degrees to 45 degrees F.; average January temperature is 28 degrees F.; and the average July temperature is 56 degrees F. The frost-free season is less than 50 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Mt. Hood soils. Mt. Hood soils are loamy-skeletal.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderately rapid permeability.
USE AND VEGETATION: Recreation, timber production, and wildlife. Dominant overstory vegetation is silver fir, noble fir, Douglas-fir, western hemlock, mountain hemlock, lodgepole pine, and western white pine; understory is huckleberry, lupine, beargrass and other shrubs and herbs.
DISTRIBUTION AND EXTENT: Cascade Mountains of northwest Oregon. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Clackamas County, Oregon, 1975.
ADDITIONAL DATA: Characterization data for one profile (FS64Oreg-045-45(1-4) by Oregon State University. Unpublished.
NSTH 17, RECLASSIFICATION ONLY, 3/95