LOCATION CRUTCH OREstablished Series
TAXONOMIC CLASS: Sandy-skeletal, mixed, mesic Aquentic Haplorthods
TYPICAL PEDON: Crutch cobbly loamy coarse sand, forested. (Colors are for moist soil unless otherwise noted.)
0i--0 to 1 inch; needles, twigs, leaves, and cones.
0e--1 to 2 inches; decomposed organic matter; abrupt wavy boundary.
E--2 to 4 inches; dark gray (10YR 4/1) cobbly loamy coarse sand, gray (10YR 6/1) dry; single grained, loose, nonsticky and nonplastic; many fine and medium roots; many fine and very fine irregular pores; 15 percent cobbles and 10 percent gravel; strongly acid (pH 5.2); abrupt wavy boundary. (1 to 4 inches thick)
Bs1--4 to 11 inches; dark brown (7.4YR 3/2) cobbly loamy coarse sand, brown (10YR 4/3) dry; common streaks of dark reddish brown (5YR 3/2) and very dark grayish brown (10YR 3/2); massive; soft, friable, nonsticky and nonplastic; many fine and medium roots; many fine and very fine irregular pores; 20 percent cobbles and 10 percent gravel; strongly acid (pH 5.5); gradual wavy boundary. (4 to 9 inches thick)
Bs2--11 to 22 inches; dark brown (7.5YR 3/2) cobbly loamy coarse sand; brown (10YR 4/3) dry; common streaks of dark reddish brown (5YR 3/2) and very dark grayish brown (10YR 3/2); massive; soft, friable, nonsticky and nonplastic; many fine and medium roots; many very fine irregular pores; 20 percent cobbles and 10 percent gravel; strongly acid (pH 5.5); gradual wavy boundary. (7 to 17 inches thick)
BCs--22 to 30 inches; brown (7.5YR 4/4) very cobbly loamy coarse sand, brown (10YR 5/3) dry; many fine and medium faint dark brown (10YR 3/3) and dark yellowish brown (10YR 4/4) mottles; massive; soft, friable, nonsticky and nonplastic; many fine and medium roots; many fine and very fine irregular pores; 35 percent cobbles and 20 percent gravel; strongly acid (pH 5.5); gradual wavy boundary. (4 to 10 inches thick)
Cd--30 to 62 inches; mottled colors of dark grayish brown (10YR 4/2), brown (10YR 5/3), yellowish brown (10YR 5/4) and gray (10YR 5/1), and light brownish gray (10YR 6/2) clay, extremely cobbly coarse sand; massive; weakly consolidated; very hard, very firm, brittle; many very fine and fine irregular pores; 50 percent cobbles and 20 percent gravel; strongly acid (pH 5.5).
TYPE LOCATION: Clackamas County, Oregon; 300 feet west of the intersection of Welches Road on U. S. Highway 26; SE1/4SE1/4SE1/4 section 32, T. 2 S., R. 7 E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 47 to 52 degrees F. The soils are usually moist but are dry for less than 45 consecutive days during the summer. Thickness of the solum and the depth to the densic contact is 20 to 40 inches. The particle-size control section averages 35 to 60 percent rock fragments.
The E horizon has value of 4 or 5 moist and 6 or 7 dry and a chroma of 1 moist and dry. It has 10 to 20 percent cobbles and 5 to 15 percent gravel. It is very strongly to strongly acid.
The Bs horizon has a hue of 7.5YR or 10YR, value of 3 or 4 moist, 4 or 5 dry and chroma of 2 or 3 moist, 3 dry. It is cobbly or very cobbly loamy coarse sand. It is very strongly to strongly acid. It has 5 to 20 percent gravel, 10 to 30 percent cobbles and 0 to 5 percent stones. Some pedons contain firm aggregates. These aggregates along with the streak seen in the modal profile commonly have 5YR hues.
The BCs horizon has a hue of 7.5YR or 10YR, value of 4 moist, 5 or 6 dry and chroma of 3 or 4 moist and dry. It is very cobbly loamy coarse and or extremely cobbly coarse sand. It has 15 to 30 percent gravel, 20 to 35 percent cobbles.
The C horizon has hue of 10YR or 2.5Y, value of 4 or 5 moist, 5 or 6 dry and chroma dominantly of 2 but with variegations ranging from 1 through 4. It is brittle, firm or very firm and is weakly consolidated. It has 30 percent gravel, 30 to 50 percent cobbles and a few stones.
COMPETING SERIES: There are no other series in this family. The Fahey series is similar but it has a frigid soil temperature regime.
GEOGRAPHIC SETTING: Crutch soils are on gently sloping stream terraces in the foothills of the Cascade Mountains. They formed in glacial outwash at elevations of 500 to 2,000 feet. Slopes are 0 to 10 percent. The climate is characterized by cool wet winters and moist warm summers. The mean annual temperature is 46 to 50 degrees F. The mean January temperature is 34 degrees F., and the mean July temperature is 64 degrees F. The frost-free season is 80 to 130 days. The mean annual precipitation is 80 to 100 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: This is the Multorpor soil. Multorpor soils lack a spodic horizon.
DRAINAGE AND PERMEABILITY: Moderately well drained; slow runoff; moderately rapid permeability. There is a perched water table above the consolidated layer from December to April.
USE AND VEGETATION: Used mainly for recreation, limited timber production and wildlife. Vegetation is dominated by Douglas-fir, western hemlock, western redcedar, red alder, salal, rhododendron, swordfern and oxalis.
DISTRIBUTION AND EXTENT: Mountain valleys of the Cascade Mountains in northern Oregon; MLRA 3. The series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Clackamas County, Oregon (Bull Run-Sandy Area), 1965.
REMARKS:
ADDITIONAL DATA: Characterization data for one pedon (FS62Oreg-045-7, 1-7) by Oregon State University. Unpublished.