LOCATION AGNEW                   WA

Established Series
Rev. LJH/RJE
09/2015

AGNEW SERIES


The Agnew series consists of very deep, somewhat poorly drained soils that formed in glaciomarine sediments. These soils are on terraces and terrace escarpments. Slopes are 0 to 50 percent. The average annual precipitation is about 20 inches and the mean annual temperature is about 49 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Aquic Haploxeralfs

TYPICAL PEDON: Agnew silt loam, pasture. (Colors are for moist soil unless otherwise noted. All textures are apparent field textures.)

Ap--0 to 8 inches; brown (10YR 4/3) silt loam, pale brown (10YR 6/3) dry; weak fine and very fine subangular blocky structure; slightly hard, friable, sticky and plastic; many fine and very fine roots; many fine and very fine irregular and tubular pores; slightly acid (pH 6.2); clear smooth boundary. (4 to 8 inches thick)

Bt1--8 to 18 inches; yellowish brown (10YR 5/4) silty clay loam, light gray (2.5Y 7/2) dry; common medium distinct dark yellowish brown (10YR 4/4) mottles, light yellowish brown (10YR 6/4) dry; moderate fine and medium angular blocky structure; very hard, firm, very sticky and very plastic; many fine and very fine roots; many fine and very fine irregular, and common fine and very fine tubular pores; common prominent clay films lining pores and on faces of peds; slightly acid (pH 6.2); clear smooth boundary. (8 to 18 inches thick)

Bt2--18 to 28 inches; dark yellowish brown (10YR 4/4) clay loam, light yellowish brown (10YR 6/4) dry; many medium distinct light brownish gray (2.5Y 6/2) and pale brown (10YR 6/3) mottles, light gray (2.5Y 7/2) dry; moderate fine and medium angular blocky structure; very hard, firm, very sticky and very plastic; common fine and very fine roots; many fine and very fine irregular, and common fine and very fine tubular pores; common distinct clay films lining pores and on faces of peds; slightly acid (pH 6.2); gradual smooth boundary. (4 to 12 inches thick)

Bt3--28 to 35 inches; yellowish brown (10YR 5/4) clay loam, light yellowish brown (10YR 6/4) dry; many medium distinct light brownish gray (2.5Y 6/2) and pale brown (10YR 6/3) mottles, light gray (2.5Y 7/2) dry; moderate fine and medium angular blocky structure; very hard, firm, sticky and very plastic; common fine and very fine roots; common fine and very fine irregular and tubular pores; common distinct clay films lining pores and on faces of peds; moderately acid (pH 6.0); clear wavy boundary. (7 to 12 inches thick)

BCt--35 to 46 inches; light olive brown (2.5Y 5/4) silty clay loam, light yellowish brown (2.5Y 6/4) dry; many medium distinct light brownish gray (2.5Y 6/2) and pale brown (10YR 6/3) mottles, light gray (2.5Y 7/2) dry; weak fine and medium angular blocky structure; very hard, firm, very sticky and very plastic; few fine and very fine roots; common fine and very fine tubular, and few very fine irregular pores; common distinct clay films lining pores; moderately acid (pH 6.0); clear smooth boundary. (6 to 11 inches thick)

C--46 to 60 inches; olive brown (2.5Y 4/4) stratified silty clay loam, silt loam and sandy loam; pale yellow (2.5Y 7/4) dry; common medium distinct light brownish gray (2.5Y 6/2) and pale brown (10YR 6/3) mottles, light gray (2.5Y 7/2) dry; massive; slightly hard to very hard, friable to firm, slightly sticky to sticky, slightly plastic to plastic; few fine and very fine roots; common fine and very fine tubular pores; moderately acid (pH 6.0).

TYPE LOCATION: Clallam County, Washington; 500 feet south and 1,000 feet west of the northeast corner of sec. 7, T. 30 N., R. 4 W.

RANGE IN CHARACTERISTICS: The particle-size control section has 0 to 5 percent pebbles. The mean annual soil temperature is estimated to range from 51 degrees F. to 53 degrees F. The soil is dry for 45 to 60 consecutive days in the moisture control section.

The A horizon has hue of 10YR or 2.5Y, value of 3 through 5 moist, 6 or 7 dry and chroma of 2 or 3. This horizon has mottles in some pedons. It has granular or subangular blocky structure. Most areas have been plowed. It is slightly acid or moderately acid.

The Bt horizon has value of 4 through 6 moist, 6 or 7 dry and chroma of 2 through 4. It is heavy silt loam, silty clay loam or clay loam. Some pedons have thin layers of silty clay. This horizon has angular blocky or prismatic structure. It is moderately acid or slightly acid.

The C horizon has hue of 10YR, 2.5Y or 5Y, value of 4 through 6 moist, 6 or 7 dry and chroma of 1 through 4. It is stratified and is predominantly silt loam and silty clay loam with thinner layers of sandy loam, loamy sand, and loam. It is moderately acid through neutral.

COMPETING SERIES: These are the tentative Odin and the provisional Volke series. Odin soils are dry for 60 to 90 consecutive days and are high in volcanic ash. Volke soils are dry for 60 to 90 consecutive days and have a massive compact C horizon within 40 inches.

GEOGRAPHIC SETTING: Agnew soils are on terraces and terrace escarpments at elevations of 50 to 400 feet. They formed in glaciomarine sediments. Slopes are 0 to 50 percent. The soils are in a mild marine climate and have cool, dry summers and cool, moist winter. Average annual precipitation is 15 to 25 inches. Average January temperature is about 38 degrees F., average July temperature is about 60 degrees F., and the mean annual temperature is about 49 degrees F. Frost-free season (28 degrees F.) is 170 to 200 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cassolary, Clallam, Dick, Hoypus, Lummi, and Puget soils. All these soils lack an argillic horizon. Also, Clallam soils are loamy-skeletal and have a paralithic contact between 20 and 40 inches; Dick soils are sandy; and Hoypus soils are sandy-skeletal.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow runoff; moderately slow or slow permeability.

USE AND VEGETATION: Irrigated cropland and pasture are the principal uses. Some areas are used as homesites. Native vegetation is Douglas-fir, red alder, western redcedar, western hemlock and bigleaf maple. Understory species include salal, elderberry, western swordfern and bedstraw. Principal crops are alfalfa and grass hay, raspberries, peas, oats, barley, corn silage, mint and pasture.

DISTRIBUTION AND EXTENT: Northeastern Olympic Peninsula, Washington. This series is inextensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Clallam County, Washington, 1943.

REMARKS: Classification changed 4/94 because of recent amendments to Soil Taxonomy.




National Cooperative Soil Survey
U.S.A.