LOCATION ROUNDTREE WA
Established Series
IRD. DRU/EED
07/2017
ROUNDTREE SERIES
Landscape--river valleys
Landform--depressions, overflow stream channels
Slope--0 to 5 percent
Parent material--alluvium
Mean annual precipitation--about 1500 mm
Mean annual air temperature--about 11 degrees C
Depth class--very deep
Drainage class--poorly drained
Soil moisture regime--aquic
Soil temperature regime--mesic
Soil moisture subclass--typic
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, nonacid, mesic Fluvaquentic Humaquepts
TYPICAL PEDON: Roundtree loam, cultivated (When described on October 16, 2015, the soil was moist to a depth of 125 cm and wet below that depth.)
A1--0 to 15 cm; loam, very dark grayish brown (10YR 3/2) moist, brown (10YR 5/3) dry; moderate fine subangular blocky structure; soft, friable, slightly sticky and slightly plastic; common very fine and fine and few medium roots; common very fine and fine tubular and few medium irregular pores; 10 percent fine prominent strong brown (7.5YR 4/6) masses of oxidized iron lining pores and 20 percent medium faint dark gray (7.5YR 4/1) iron depletions lining pores; strongly acid (pH 5.4); abrupt smooth boundary
A2--15 to 43 cm; loam, very dark grayish brown (10YR 3/2) moist, brown (10YR 5/3) dry; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and many fine roots; common very fine and fine tubular and few medium irregular pores; 20 percent fine prominent strong brown (7.5YR 4/6) masses of oxidized iron lining pores and 30 percent medium faint dark gray (7.5YR 4/1) iron depletions lining pores; strongly acid (pH 5.4); clear wavy boundary
Bg1--43 to 55 cm; loam, dark gray (10YR 4/1) moist, light brownish gray (10YR 6/2) dry; moderate fine subangular blocky structure; moderately hard, firm, slightly sticky and slightly plastic; common very fine roots; common very fine tubular and few medium irregular pores; 20 percent faint very dark grayish brown (10YR 3/2) organic stains; 30 percent medium prominent dark brown (7.5YR 3/4) iron-manganese masses lining pores; moderately acid (pH 6.0); clear wavy boundary
Bg2--55 to 65 cm; loam, dark gray (10YR 4/1) moist, light brownish gray (10YR 6/2) dry; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; few very fine tubular pores; 35 percent coarse prominent strong brown (7.5YR 4/6) masses of oxidized iron on faces of peds; slightly acid (pH 6.1); abrupt smooth boundary
Bg3--65 to 110 cm; clay loam, dark gray (10YR 4/1) moist, light brownish gray (10YR 6/2) dry; strong fine subangular blocky structure; moderately hard, firm, moderately sticky and moderately plastic; few very fine roots; common very fine tubular pores; 40 percent coarse prominent strong brown (7.5YR 4/6) masses of oxidized iron on faces of peds; slightly acid (pH 6.1); clear wavy boundary
Bg4--110 to 125 cm; loam, dark gray (10YR 4/1), light brownish gray (10YR 6/2) dry; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; few very fine tubular pores; 40 percent coarse prominent strong brown (7.5YR 4/6) masses of oxidized iron on faces of peds; slightly acid (pH 6.1); abrupt smooth boundary
Cg1--125 to 140 cm; fine sandy loam, very dark bluish gray (10B 3/1) reduced, dark grayish brown (2.5Y 4/2) dry; massive; slightly hard, friable, nonsticky and nonplastic; few very fine roots; slightly acid (pH 6.2); abrupt smooth boundary
Cg2--140 to 160 cm; loamy sand, very dark bluish gray (10B 3/1) reduced, dark grayish brown (2.5Y 4/2) dry; single grain; loose, nonsticky and nonplastic; 5 percent wood fragments and 10 percent gravel
TYPE LOCATION: Lewis County, Washington, about 200 m south of the boundary with Thurston County; about 600 m east and 195 m south of the northwest corner of section 26, T. 15 N., R. 3 W., Willamette Meridian; Rochester, Washington, U.S. Geological Survey quadrangle; latitude 46.7628520 degrees north, longitude 123.0268980 degrees west, WGS 84 (coordinates determined with a GPS)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--10 to 12 degrees C
Umbric epipedon thickness--25 to 50 cm
Depth to aquic conditions--at the surface to a depth of 30 cm
Particle-size control section--18 to 35 percent clay (weighted average); 0 to 10 percent gravel (weighted average)
A1 horizon
Value--3 to 5 dry
Chroma--1 or 2 moist, 2 or 3 dry
Fine-earth texture--loam, silt loam
Clay content--18 to 27 percent
Organic carbon content--2 to 6 percent
Reaction (pH)--5.1 to 5.6
Thickness--10 to 20 cm
A2 horizon
Value--3 to 5 dry
Chroma--1 or 2 moist, 2 or 3 dry
Fine-earth texture--loam, silt loam, clay loam
Clay content--18 to 35 percent
Organic carbon content--2 to 6 percent
Reaction (pH)--5.1 to 5.6
Thickness--15 to 30 cm
Bg horizon
Hue--10YR, 7.5YR
Value--3 to 5 moist, 4 to 7 dry
Chroma--1 to 4 moist, 2 to 4 dry
Fine-earth texture--loam, clay loam, silt loam
Clay content--18 to 35 percent
Organic carbon content--0.3 to 1.75 percent
Reaction (pH)--5.1 to 6.5
Combined thickness--50 to 125 cm
Cg horizon
Hue--2.5Y, 5Y, 10B, neutral
Value--3 or 4 moist, 3 to 5 dry
Chroma--neutral, 1 to 3 moist, 2 to 3 dry
Fine-earth texture--loamy sand, sandy loam, fine sandy loam, loam, clay loam
Clay content--0 to 30 percent
Organic carbon content--0 to 1 percent
Gravel content--0 to 30 percent
Wood fragment content--0 to 15 percent
Reaction (pH)--5.1 to 6.5
COMPETING SERIES:
Sammamish--8 to 25 percent clay and less than 5 percent coarse fragments in particle-size control section; no aquic conditions within 30 cm of the soil surface
Wallkill--buried organic horizons within 100 cm of the soil surface; no neutral hue or chroma; saturated hydraulic conductivity of moderately high to very high
GEOGRAPHIC SETTING:
Elevation--5 to 55 m
Mean annual precipitation--1200 to 1800 mm
Mean annual air temperature--10 to 11 degrees C
Frost-free period--150 to 200 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Eld--no aquic conditions; in slightly convex to linear positions of flood plains and on alluvial terraces
Fordprairie--no aquic conditions within 50 cm of the soil surface; in concave to linear positions of flood plains
Maytown--less than 15 percent sand in particle-size control section; no aquic conditions within 50 cm of the soil surface; in concave to linear positions of flood plains
Scatter--less than 18 percent clay in particle-size control section; no aquic conditions; on convex natural levees and alluvial terraces
Elma--10 percent clay or less in lower part of particle-size control section; no aquic conditions; on convex natural levees and alluvial terraces
Rennie--less than 15 percent sand in particle-size control section; in oxbows, backswamps, and concave depressions
Salzer--40 to 60 percent clay in particle-size control section; frequent, very long periods of ponding; in oxbows and backswamps
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--poorly drained
Depth to apparent seasonal water table--at the surface to a depth of 30 cm at times in November through April; 20 to 100 cm in October, May, and June
Flooding--frequent, brief periods in November through March
Ponding--frequent, long periods in November through April
Saturated hydraulic conductivity (Ksat)--moderately low to high throughout
Ponding and the seasonal high water table in some pedons may be altered by artificial drainage.
Flooding in some pedons may be altered by flood protection structures.
USE AND VEGETATION:
Use--wildlife habitat, hay and crop production in cleared and/or artificially drained or protected areas
Native vegetation--red alder, black cottonwood, Oregon ash, western redcedar, salmonberry, redosier dogwood, willow, Douglas spirea, slough sedge, bulrush
DISTRIBUTION AND EXTENT: Western Washington; MLRA 2; small extent
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Grays Harbor County, Washington; 2016; name from Roundtree Creek in Grays Harbor County, Washington
REMARKS:
Diagnostic horizons and other features in this pedon
*Particle-size control section--zone from 25 to 100 cm
*Umbric epipedon--zone from the surface to a depth of 43 cm
*Cambic horizon--zone from 43 to 125 cm
*Aquic conditions--zone from the surface to a depth of 160 cm
*Endosaturation--zone from the surface to a depth of 160 cm
*Redoximorphic depletions with chroma of 2 or less--zone from the surface to a depth of 125 cm
*Reduced matrix--zone from 125 to 160
4/2017--The Roundtree series was proposed as a result of an update project. The official series description was developed according to SSR01 Technical Note--Content and Format of Official Series Descriptions (revised 12/2015). Further field investigation and laboratory sampling in the flood plains of MLRA 2 is recommended.
National Cooperative Soil Survey
U.S.A.