LOCATION BLODGETT OREstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic, frigid, shallow Typic Dystrudepts
TYPICAL PEDON: Blodgett very gravelly medial loam - woodland, on a 70 percent northeast-facing slope at 1,800 feet elevation. (Colors are for moist soil unless otherwise noted. When described on October 31, 2000, the soil was moist throughout.)
Oi--0 to 1 inch; slightly decomposed plant material; abrupt smooth boundary.
A--1 to 6 inches; brown (10YR 4/3), very gravelly medial loam, yellowish brown (10YR 5/4) dry; weak very fine subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; moderately smeary; many very fine, fine and medium, and few coarse roots; many very fine and fine interstitial pores; 5 percent paragravel and 2 percent paracobbles; 40 percent gravel and 5 percent cobbles; very strongly acid pH (4.9); NaF pH 10.5; clear smooth boundary. (3 to 5 inches thick)
Bw1--6 to 11 inches; yellowish brown (10YR 5/4), extremely gravelly loam, light yellowish brown (10YR 6/4) dry; moderate fine subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; moderately smeary; common very fine and fine, and few medium and coarse roots; many fine irregular pores; 15 percent paragravel and 5 percent paracobbles; 50 percent gravel, 10 percent cobbles, and 5 percent stones; strongly acid pH (5.2); NaF pH 9.5; gradual wavy boundary.
Bw2--11 to 16 inches; light yellowish brown (10YR 6/4), extremely cobbly loam, very pale brown (10YR 7/4) dry; moderate fine and medium subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; weakly smeary; common fine and medium, and few coarse roots; many fine irregular pores; 15 percent paragravel and 5 percent paracobbles; 40 percent cobbles, 20 percent gravel, and 5 percent stones; strongly acid pH (5.4); NaF pH 9.0; abrupt wavy boundary. (Combined thickness of the Bw horizon is 9 to 12 inches)
Cr--16 to 19 inches; weakly cemented sandstone; abrupt wavy boundary. (1 to 3 inches thick)
R--19 inches; very strongly cemented sandstone, with roots along fracture planes; fractured at intervals of 4 to 18 inches.
TYPE LOCATION: Benton County, Oregon; about 1.5 miles east of Grass Mountain; located about 1,320 feet south and 1,100 feet west of the northeast corner of section 22, T. 13 S., R. 8 W. (Latitude 44 degrees, 25 minutes, 49 seconds N.; Longitude 123 degrees, 38 minutes, 31 seconds W.; Grass Mountain, OR 7.5 minute USGS quad; NAD 1927)
RANGE IN CHARACTERISTICS:
Soil moisture: Udic moisture regime
Mean annual soil temperature: 43 to 47 degrees F., and the mean summer soil temperature is above 47 degrees F. with an O horizon present
Solum thickness: 12 to 17 inches
Depth to bedrock: 12 to 17 inches to a paralithic contact; 13 to 20 inches to a lithic contact
Bedrock hardness classes: paralithic contact ranges from very weakly cemented to moderately cemented; lithic contact ranges from strongly cemented to indurated
Particle-size control section:
Clay content: 15 to 25 percent apparent clay content (by field estimates)
Coarse fragments: 35 to 70 percent rock fragments; 10 to 20 percent pararock fragments
Hue: 10YR or 7.5YR
Soil reaction: Very strongly acid or strongly acid
A horizon
Value: 2 to 4 moist, 3 to 5 dry
Chroma: 2 or 3 moist, 2 to 4 dry
Texture: GRV-medial L
Clay content: 12 to 20 percent
Rock fragments: 35 to 50 percent gravel, 5 to 10 percent cobbles, 0 to 10 percent stones
Pararock fragments: 5 to 10 percent paragravel and 0 to 5 percent paracobbles.
Organic matter content: 5 to 10 percent
Andic feature: moist bulk density of 0.8 to 0.9 grams per cubic centimeter, phosphate retention of 85 percent or greater, acid-oxalate extractable aluminum plus one-half iron of 1.0 to 2.0 percent, and 15-bar moisture (air-dried) of 15 to 30 percent
Bw horizon
Value: 4 to 6 moist, 5 to 7 dry
Chroma: 4 through 6 moist and dry
Texture: CBX-L, GRV-L, or GRX-L
Clay content: 15 to 25 percent
Rock fragments: 20 to 50 percent gravel, 10 to 40 percent cobbles, 0 to 10 percent stones
Pararock fragments: 10 to 20 percent paragravel and 0 to 5 percent paracobbles
COMPETING SERIES: There are no competing series. The Euchrand series has a similar classification.
Euchrand soils (OR) - have a lithic bedrock contact without paralithic contact above it; lack andic soil properties in the A horizon; lack pararock fragments in the Bw horizon
GEOGRAPHIC SETTING:
Parent material: Loamy colluvium derived from sandstone or siltstone of the Tyee and Flournoy Formations
Landform: Mountains
Landform position: Summits and shoulder slopes
Slopes: 30 to 90 percent
Elevation: 1,800 to 3,000 feet
Climate: Cool, wet winters; warm, moist summers
Mean annual temperature: 42 to 46 degrees F
Meanannual precipitation: 90 to 130 inches
Frost-free period: 70 to 120 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Burntwoods, Chintimini, Fiverivers, Grassmountain, Luckiamute, Lurnick, Maryspeak and Oldblue soils. Burntwoods, Chinitimini, Fiverivers, Grassmountain and Oldblue soils occur on summits and side slopes of mountains. Luckiamute, Lurnick and Maryspeak soils occur in a cryic temperature regime on adjacent higher mountain slopes.
Burntwoods - medial-skeletal over loamy-skeletal; greater than 60 inches to bedrock
Chintimini - loamy-skeletal; 40 to 60 inches deep to Cr over R contact
Fiverivers - fine-loamy; 20 to 40 inches deep to a paralithic contact
Grassmountain - fine-loamy; greater than 60 inches deep to a paralithic contact
Luckiamute - loamy-skeletal; less than 20 inches deep to a lithic contact
Lurnick - clayey-skeletal; 20 to 40 inches deep to a paralithic contact
Maryspeak sandy-skeletal; greater than 80 inches deep
Oldblue - fine-loamy ; greater than 60 inches deep to paralithic contact; 40 to 80 percent pararock fragments
DRAINAGE AND PERMEABILITY: Well drained; moderately rapid permeability.
USE AND VEGETATION: These soils are used for timber production, recreation, wildlife habitat and watersheds. Potential native vegetation is Douglas fir, western hemlock, salal, western swordfern, red huckleberry, cascade Oregongrape, vine maple, little prince's pine, evergreen violet, summer coralroot and Pacific trillium.
DISTRIBUTION AND EXTENT: Central portion of the Coast Range Mountains in Oregon; MLRA 1. This series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Benton County, Oregon, 2004. The name is taken from the community of Blodgett in western Benton County.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Ochric epipedon - from the mineral soil surface to a depth of 6 inches (A horizon).
Cambic horizon - from 6 to 16 inches (Bw1 and Bw2 horizons).
Andic feature - from mineral soil surface to 6 inches (A horizon). Based on lab data from similar soils and field observations. This soil does not classify into an Andic subgroup since the Lithic subgroup classifies out first in the Keys to Soil Taxonomy. Medial modifiers were used for those horizons meeting the andic subgroup criteria although not meeting andic soil properties. A proposal was submitted to NSSC (2000) to revise the definition of medial to also include those soil properties qualifying for the Andic subgroup under criteria #1 for andic soil properties.
Lithic subgroup - very strongly cemented sandstone at 19 inches
Particle-size control section (Loamy-skeletal family) - from 11 to 16 inches (Bw2 horizon).
The Cr over R bedrock is recognized as a diagnostic feature for this series.
Depths to diagnostic horizons and features are measured from the top of the first mineral horizon.
ADDITIONAL DATA: Characterization data available for S01OR003-011, NSSL, Lincoln, NE, 5/02.