LOCATION BRENNER OREstablished Series
The Brenner series consists of very deep, poorly drained soils on flood plains. They formed in recent alluvium derived from mixed sources. Slopes are 0 to 3 percent. The mean annual precipitation is about 80 inches and the mean annual temperature is about 52 degrees F.
TAXONOMIC CLASS: Fine-silty, mixed, superactive, acid, isomesic Fluvaquentic Humaquepts
TYPICAL PEDON: Brenner silt loam - pasture, at an elevation of 12 feet. (Colors are for moist soil unless otherwise noted. When described on September 13, 1999, the soil was moist from the surface to a depth of 40 inches and wet below.)
Ap--0 to 7 inches; very dark grayish brown (10YR 3/2) silt loam, brown (10YR 5/3) dry; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine tubular pores; few fine distinct brown (7.5YR 4/4) iron-manganese masses on peds and in pores; moderately acid (pH 5.8); clear smooth boundary.
A--7 to 12 inches; dark brown (10YR 3/3) silty clay loam, brown (10YR 5/3) dry; moderate fine and very fine subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; many very fine roots; many very fine tubular pores; many fine distinct brown (7.5YR 4/4) iron-manganese masses on peds and in pores; many faint dark grayish brown (10YR 4/2) iron depletions on peds; strongly acid (pH 5.5); clear smooth boundary. (Combined thickness of the A horizon is 10 to 14 inches)
Bw1--12 to 18 inches; dark grayish brown (10YR 4/2) silty clay loam, light brownish gray (10YR 6/2) dry; moderate medium and fine subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; many very fine roots; many very fine tubular pores; many fine and medium distinct brown (7.5YR 4/4) iron-manganese masses on peds and in pores; strongly acid (pH 5.5); clear smooth boundary.
Bw2--18 to 26 inches; dark grayish brown (10YR 4/2) silty clay loam, light brownish gray (10YR 6/2) dry; moderate medium subangular blocky structure; moderately hard, firm, moderately sticky and moderately plastic; few very fine roots; many very fine tubular pores; common fine and medium prominent dark reddish brown (5YR 3/4) iron-manganese masses on peds and in pores; strongly acid (pH 5.5); gradual smooth boundary. (Combined thickness of the Bw horizon is 12 to 36 inches)
BC--26 to 40 inches; very dark gray (10YR 3/1) silty clay loam, grayish brown (2.5Y 5/2) dry; weak coarse prismatic structure; hard, firm, moderately sticky and moderately plastic; few very fine roots; common fine, very fine and few medium and coarse pores; many fine and medium prominent yellowish red (5YR 4/6) iron-manganese masses in pores; strongly acid (pH 5.5); gradual smooth boundary. (0 to 35 inches thick)
Cg1--40 to 55 inches; greenish black (10Y 2.5/1) silty clay, very dark gray (10YR 3/1) dry; massive; very hard, firm, moderately sticky and moderately plastic; common very fine tubular pores; common fine and medium prominent strong brown (7.5YR 4/6) iron-manganese masses in pores; moderately acid (pH 5.8); gradual smooth boundary.
Cg2--55 to 60 inches; dark greenish gray (10Y 3/1) silty clay, grayish brown (2.5Y 5/2) and olive gray (5Y 5/2) dry; massive; extremely hard, very firm, moderately sticky and moderately plastic; few very fine tubular pores; moderately acid (pH 5.8).
TYPE LOCATION: Tillamook County, Oregon; about 1,100 feet south and 250 feet west of the northeast corner of section 20, T. 1 S., and R. 9 W. ; USGS Tillamook topographic quadrangle; Latitude 45 degrees, 27 minutes, 38 seconds N. and Longitude 123 degrees, 49 minutes, 25 seconds W. NAD 27.
RANGE IN CHARACTERISTICS: The soil is saturated with water during the winter, and unless drained has a water table at a depth of less than 40 inches during most of the growing season. Aquic conditions with redox depletions and concentrations or masses occur at depths of less than 14 inches. The mean annual soil temperature is 49 to 54 degrees F. The difference between mean summer and mean winter soil temperature varies from 5 to 9 degrees F. The solum is extremely acid through strongly acid. The umbric epipedon is 10 to 14 inches thick. The particle-size control section averages 18 to 30 percent clay and less than 15 percent coarser than very fine sand.
The A or Ap horizon has hue of 10YR and value of 2 or 3 moist, 4 or 5 dry, and chroma of 1 or 2 moist and dry. It has faint to prominent redoximorphic features. Texture is silt loam or silty clay loam with 20 to 35 percent clay.
The Bw or Bg horizon and BC horizon, when present, has hue of 10YR or 2.5Y, value of 3, 4 or 5 moist, 5 to 7 dry, and chroma of 1 or 2 moist and dry. It has distinct to prominent redoximorphic features. Texture is silty clay loam or silt loam with 18 to 35 percent clay, but thin lenses of finer material are in some pedons.
The C or Cg horizon has hue of 10YR to 10Y, value of 2.5 to 5 moist, 3 to 7 dry, and chroma of 2 to neutral. Texture is silty clay loam or silty clay with 27 to 50 percent clay. There are few strata of coarser textures in some pedons. It is extremely acid through moderately.
COMPETING SERIES: These are the Nestucca and the similar Willanch series. Nestucca soils have aquic conditions with depletions and redox concentrations at depths of 16 to 20 inches and have an umbric epipedon 14 to 20 inches thick. Willanch soils are coarse-loamy.
GEOGRAPHIC SETTING: The Brenner soils are in swales on flood plains adjacent to stream terraces. Slopes are 0 to 3 percent. Elevations range from 10 to 700 feet. The soils formed in silty mixed recent alluvium derived from basic igneous and sedimentary rocks. Water ponds in winter after heavy rains or when streams overflow leaving thin layers of fresh alluvium on the surface. The soils are characterized by cool wet winters and cool moist summers with fog. The mean annual precipitation is 60 to 100 inches. The average January temperature is 38 to 45 degrees F. and the average July temperature is 58 to 64 degrees F. The mean annual temperature is 48 to 53 degrees F. The frost-free season is 160 to 300 days. This soil is on the Ingram geomorphic surface.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Knappa, Nehalem, and the competing Nestucca soils. Knappa and Nehalem soils are well drained. Nehalem and Nestucca soils are on flood plains. Knappa soils are on adjacent terraces.
DRAINAGE AND PERMEABILITY: Poorly drained; very slow runoff or ponded; slow permeability. The soil is frequently flooded for brief periods during the winter and are saturated with water for several months each year. An apparent high water table is at its highest level from December through April.
USE AND VEGETATION: Most of the these soils have been cleared and drained. They are used for pasture, hay and silage, and wildlife habitat. A small acreage is still in forest of dominantly red alder with rushes and sedges.
DISTRIBUTION AND EXTENT: Flood plains of coastal river valleys in Western Oregon; MLRA 4a. The series is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Clastop County (Astoria Area), Oregon, 1945.
REMARKS: Diagnostic features and horizons include:
Umbric epipedon - 0 to 12 inches thick (Ap and A horizons)
Cambic horizon - 12 to 26 inches (Bw1 and Bw2 horizons)
Distinct redox concentrations - 7 to 12 inches (A horizon)
Aquic moisture regime - aquic conditions between 16 and 20 inches with chroma of 2 or less and redox concentrations directly below the umbric epipedon beginning at 12 inches (Bw1 and Bw2 horizon).
This revision reflects a change in the modal pedon to a location which more accurately reflects the flooding hazard.
ADDITIONAL DATA: Lincoln Laboratory samples 83T7171-7172 and 93OR-057-009.