LOCATION MARYSPEAK OREstablished Series
TAXONOMIC CLASS: Sandy-skeletal, isotic Andic Dystrocryepts
TYPICAL PEDON: Maryspeak gravelly medial sandy loam - woodland, on a 10 percent south-facing slope at 3,530 feet elevation. (Colors are for moist soil unless otherwise noted. When described on August 9, 2000, the soil was moist throughout.)
Oi--0 to 1 inch; slightly decomposed plant material; abrupt smooth boundary
Oe--1 to 2 inch; moderately decomposed plant material; abrupt smooth boundary
A1--2 to 4 inches; dark brown (7.5YR 3/2) gravelly medial sandy loam, brown (7.5YR 4/4) dry; weak very fine granular structure; soft, very friable, nonsticky and nonplastic; moderately smeary; many very fine and fine, common medium, and few coarse roots; many very fine and fine tubular pores; 20 percent fine gravel and 3 percent cobbles; few slightly weathered, strongly cemented gabbro fragments from local volcanic intrusives; rock fragments are dominantly fine in size, and both subangular and platy in shape; very strongly acid (pH 5.0); NaF pH 10.5; clear smooth boundary.
A2--4 to 9 inches; dark brown (7.5YR 3/3) gravelly medial sandy loam, brown (7.5YR 5/4) dry; weak very fine granular structure; soft, very friable, nonsticky and nonplastic; moderately smeary; many very fine and fine, common medium, and few coarse roots; many very fine and fine tubular pores; 20 percent fine gravel and 3 percent cobbles; few slightly weathered, strongly cemented gabbro fragments from local volcanic intrusives; rock fragments are dominantly fine in size, and both subangular and platy in shape; strongly acid (pH 5.1); NaF pH 10.8; clear smooth boundary. (Combined thickness of the A horizon is 7 to 9 inches)
BA--9 to 13 inches; brown (10YR 4/3) very gravelly sandy loam, yellowish brown (10YR 5/6) dry; moderate fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; weakly smeary; common very fine and fine, and few medium and coarse roots; many very fine and fine tubular pores; 35 percent gravel and 5 percent cobbles; few slightly weathered, strongly cemented gabbro fragments from local volcanic intrusives; rock fragments are dominantly fine in size, and both subangular and platy in shape; strongly acid (pH 5.2); NaF pH 10.7; clear smooth boundary. (3 to 6 inches thick)
Bw--13 to 34 inches; dark yellowish brown (10YR 4/4) very gravelly loamy very fine sand, yellowish brown (10YR 5/6) dry; weak fine subangular blocky structure; loose, loose, nonsticky and nonplastic; weakly smeary; common very fine and fine, and few medium and coarse roots; many fine interstitial and few very fine tubular pores; 40 percent gravel and 5 percent cobbles; few slightly weathered, strongly cemented gabbro fragments from local volcanic intrusives; rock fragments are dominantly fine in size, and both subangular and platy in shape; strongly acid (pH 5.2); NaF pH 10.3; gradual smooth boundary. (20 to 30 inches thick)
BC--34 to 59 inches; dark yellowish brown (10YR 4/4) very gravelly loamy fine sand, yellowish brown (10YR 5/6) dry; coarse, brown (10YR 4/3) mottles derived from mixing; weak fine subangular blocky structure; loose, loose, nonsticky and nonplastic; weakly smeary; few fine and medium roots; many fine and medium interstitial and few very fine tubular pores; 35 percent gravel and 10 percent cobbles; few slightly weathered, strongly cemented gabbro fragments from local volcanic intrusives; rock fragments are dominantly fine in size, and both subangular and platy in shape; strongly acid (pH 5.4); NaF pH 10.0; gradual wavy boundary. (18 to 36 inches thick)
C--59 to 73 inches; yellowish brown (10YR 5/4) very gravelly sandy loam, brownish yellow (10YR 6/6) dry; massive; loose, nonsticky and nonplastic; weakly smeary; many fine and medium interstitial and few very fine tubular pores; 35 percent gravel and 10 percent cobbles; few slightly weathered, strongly cemented gabbro fragments from local volcanic intrusives; rock fragments are dominantly fine in size, and both subangular and platy in shape; strongly acid (pH 5.4); NaF pH 10.2.
TYPE LOCATION: Benton County, Oregon; on Grass Mountain; located about 720 feet south and 2,150 feet east of northwest corner of section 21, T. 13 S, R. 8 W. (Latitude 44 degrees, 25 minutes, 56 seconds N.; Longitude 123 degrees, 40 minutes, 14 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: 4 to 6 feet or more
Depth to bedrock: greater than 80 inches
Particle-size control section:
Clay content- 8 to 12 percent clay (by field estimate)
Sand content- 75 to 90 percent sand (by field estimate), with less than 20 percent very fine sand
Rock fragment content- 35 to 50 percent rock fragments, dominantly fine in size with both channer and subangular shaped fragments present; subangular fragments dominate
Hue: 10YR or 7.5YR
A horizon
Value - 3 or 4 moist, 4 or 5 dry
Chroma - 2 or 3 moist, 4 dry
Texture - GR-medial SL
Clay content - 10 to 15 percent
Rock fragment content - 15 to 30 percent gravel and 0 to 5 percent cobbles
Organic matter content: 5 to 10 percent
Andic soil features - moist bulk density of 0.75 to 1.0 grams per cubic centimeter (by field estimates), phosphate retention of 75 to 95 percent, acid-oxalate extractable aluminum plus one-half iron of 1.0 to 2.0 percent , and 15-bar moisture content (air-dried) of 12 to 25 percent.
Reaction - very strongly acid or strongly acid
Other features: The horizon has weakly smeary or moderately smeary consistence (by field estimate).
BA horizon
Value - 4 or 5 moist, 4 to 6 dry
Chroma - 3 or 4 moist, 4 to 6 dry
Texture - GRV-SL, GRV-LS, GRV-LFS
Clay content - 5 to 12 percent clay
Rock fragment content - 35 to 50 percent gravel and 0 to 5 percent cobbles
Reaction - very strongly acid or strongly acid
Bw horizon
Value - 4 or 5 moist, 4 to 6 dry
Chroma - 3 or 4 moist, 4 to 6 dry
Texture - GRV-LS, GRV-S, GRV-LFS
Clay content - 5 to 12 percent clay
Rock fragment content - 35 to 50 percent gravel and 0 to 5 percent cobbles
Reaction - very strongly acid or strongly acid
BC horizon
Value - 4 or 5 moist, 4 to 6 dry
Chroma - 4 to 6 moist and dry
Texture - GRV-LS, GRV-LFS, GRV-S
Clay content - 5 to 10 percent
Rock fragment content - 35 to 50 percent gravel and 0 to 10 percent cobbles
Reaction - very strongly acid or strongly acid
C horizon
Value - 5 or 6 moist, 6 or 7 dry
Chroma - 4 to 6 moist and dry
Texture - GRV-SL, GRV-LFS, GRV-LS
Clay content - 5 to 15 percent
Rock fragment content - 35 to 50 percent gravel and 0 to 10 percent cobbles
Reaction - strongly acid or moderately acid
COMPETING SERIES: This is the
Jantill (T) series.
Jantill (WA) - volcanic ash mantle 7 to 14 inches thick with 30 to 60 percent glass and meeting andic soil properties; 7 to 14 inches deep to sandy glacial till
GEOGRAPHIC SETTING:
Parent material: Sandy colluvium in ancient landslide deposits derived from a mixture of sandstone and siltstone of the Tyee and Flournoy Formations and coarse-grained intrusive igneous rocks
Landform: Mountains
Landform position: Summits, backslopes, and footslopes
Slopes: 5 to 60 percent
Elevation: 3,000 to 4,100 feet
Climate: cold, wet winters; cool, moist summers
Mean annual temperature: 41 to 45 degrees F
Mean annual precipitation: 120 to 150 inches
Frost-free period: 60 to 100 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Blodgett ,
Burntwoods ,
Chintimini ,
Fiverivers ,
Grassmountain ,
Luckiamute,
Lurnick, and
Oldblue soils. Blodgett, Burntwoods, Chinitimini, Fiverivers, Grassmountain, and Oldblue soils occur in a frigid temperature regime on adjacent lower mountain slopes. Luckiamute and Lurnick soils occur in a cryic temperature regime on adjacent mountain slopes.
Blodgett - loamy-skeletal; less than 20 inches deep to Cr over R contact
Burntwoods - medial-skeletal; greater than 60 inches deep 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
Oldblue - fine-loamy; 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, noble fir, Pacific rhododendron, common beargrass, grouse blueberry, western rattlesnake plantain, Oregon oxalis, starry false Solomon's seal, Pacific trillium, whiteveined shinleaf, and evergreen violet.
DISTRIBUTION AND EXTENT: Central portion of the Coast Range Mountains of 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 Marys Peak in western Benton County, the highest point in the Coast Range Mountains of Oregon.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Ochric epipedon - from the mineral soil surface to a depth of 9 inches (A1 and A2 horizons).
Cambic horizon - from 13 to 34 inches (Bw horizon).
Andic subgroup feature - from the mineral soil surface to 9 inches (A1 and A2 horizons). 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.
Particle-size control section (Sandy-skeletal family) - from 12 to 42 inches (1 inch of the BA horizon, Bw1 horizon, and 8 inches of the BC horizon).
Depths to diagnostic horizons and features are measured from the top of the first mineral horizon.
Classification revision 12/01 from loamy-skeletal, isotic Andic Dystrocryepts to sandy-skeletal, isotic Andic Dystrocryepts based on lab data and associated soils.
ADDITIONAL DATA: Characterization data for S01OR003-010, NSSL, Lincoln, NE., 11/01