LOCATION EKOMS OREstablished Series
TAXONOMIC CLASS: Fine-loamy, isotic, isomesic Typic Haplohumults
TYPICAL PEDON: Ekoms loam - pasture, on a 7 percent slope at an elevation of 90 feet. (When described on September 5, 1991 the soil was dry to a depth of 25 inches and moist below this depth. Colors are for moist soil unless otherwise noted.)
A---0 to 5 inches; very dark grayish brown (10YR 3/2) loam, dark yellowish brown (10YR 3/4) dry; moderate very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic, weakly smeary; many very fine and fine roots; many fine tubular pores; 10 percent gravel and 10 percent (2 to 5 mm) soft rock fragments; strongly acid (pH 5.2); abrupt smooth boundary. (4 to 9 inches thick)
BA--5 to 12 inches; dark brown (10YR 3/3) clay loam, brown (10YR 4/3) dry; moderate fine and medium subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic, weakly smeary; many very fine and fine roots; many fine and very fine tubular pores; 10 percent gravel and 10 percent (2 to 5 mm) soft rock fragments; strongly acid (pH 5.4); clear smooth boundary. (0 to 8 inches thick)
Bt1--12 to 25 inches; dark yellowish brown (10YR 3/4) gravelly clay loam, dark yellowish brown (10YR 4/4) dry; moderate medium subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; common very fine and fine roots; many very fine tubular pores; common distinct clay films on ped faces and in pores; 15 percent gravel; moderately acid (pH 5.6); clear smooth boundary.
Bt2--25 to 44 inches; dark yellowish brown (10YR 4/4) gravelly clay loam, yellowish brown (10YR 5/4) dry; moderate medium subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; few fine roots; common very fine tubular pores; common distinct clay films on ped faces and in pores; 25 percent gravel; moderately acid (pH 5.6); clear wavy boundary. (Combined thickness of the Bt horizon is 30 to 36 inches)
C---44 to 60 inches; yellowish brown (10YR 5/6) gravelly loam, brownish yellow (10YR 6/6) dry; massive; slightly hard, firm, slightly sticky and slightly plastic; few fine tubular pores; 25 percent gravel and 5 percent cobbles; moderately acid (pH 5.8).
TYPE LOCATION: Curry County, Oregon; located about 900 feet south and 300 feet east of the northwest corner of section 35, T. 32 S., R. 15 W., W.M.(Latitude 42 degrees, 45 minutes, 54 seconds N.; Longitude 124 degrees, 27 minutes, 06 seconds W.)
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 51 to 54 degrees F. The difference between mean summer and mean winter soil temperatures varies from 5 to 9 degrees F. The soils are usually moist but are dry for less than 45 consecutive days in all parts between depths of 4 and 12 inches in the four months following the summer solstice. The umbric epipedon is 10 to 20 inches thick and includes the upper part of the B horizon. Depth to bedrock is greater than 60 inches. Soil reaction is strongly acid to moderately acid throughout. Hue is 10YR or 7.5YR in the solum.
The A horizon has value of 2 or 3 moist, 3 dry and chroma of 2 to 3 moist and 3 or 4 dry. It is loam with 20 to 25 percent clay. It has 0 to 10 percent gravel and 0 to 20 percent soft rock fragments. Organic matter is 10 to 15 percent.
The BA horizon has value of 3 or 4 moist and dry and chroma of 3 or 4 moist and dry. It is clay loam or gravelly loam with 25 to 35 percent clay. It has 5 to 15 percent gravel and 0 to 20 percent soft rock fragments.
The Bt horizon has value of 3 to 5 moist, 4 or 5 dry and chroma of 3 to 6 moist and dry. It is gravelly loam, gravelly clay loam, or clay loam with 25 to 35 percent clay. It has 5 to 25 percent gravel and 0 to 20 percent soft rock fragments.
The C horizon has hue of 10YR or 2.5Y, value of 4 or 5 moist, 5 to 7 dry and chroma of 3 to 6 moist and dry. It is stratified gravelly loam, very gravelly sandy loam, or gravelly sandy clay loam with 15 to 25 percent clay. It has 20 to 40 percent gravel, 0 to 10 percent cobbles, and 0 to 30 percent soft rock fragments.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Ekoms soils occur on high stream terraces along major coastal rivers. Slopes are 0 to 12 percent. These soils formed in alluvium from mixed sources. Elevations are 50 to 200 feet. The climate is humid, characterized by cool, wet winters and cool, moist summers with fog. A strong marine influence limits the diurnal and annual range of temperature. The mean annual precipitation is 70 to 90 inches. The mean annual temperature is 50 to 53 degrees F. The frost-free period is 210 to 300 days. Ekoms soils occur on the Senecal geomorphic surface.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Euchre and Logsden series. These soils occur on an adjacent lower stream terrace. Euchre soils are somewhat poorly drained and lack an argillic horizon. Logsden soils lack an argillic horizon.
DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability.
USE AND VEGETATION: Ekoms soils are used for pasture, woodland, watershed, recreation, homesite development, and wildlife habitat. Most areas have been cleared. In uncleared areas the native vegetation is Douglas fir, western hemlock, Port Orford cedar, California laurel, bigleaf maple, tanoak, western hazel, red alder, willow, cascade Oregongrape, Pacific rhododendron, evergreen huckleberry, red huckleberry, western swordfern, western brackenfern, and forbs.
DISTRIBUTION AND EXTENT: High stream terraces of coastal river valleys in western Oregon; MLRA 1. This series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Curry County, Oregon, 1993. The source of the name is from a former post office site established in the Rogue River area upstream from Lobster Creek prior to 1900.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Umbric epipedon - from the surface to a depth of 12 inches (A, BA horizons).
Argillic horizon - from 12 to 44 inches (Bt1, Bt2 horizons).
Particle-size control section - from 12 to 32 inches (Bt1, and most of the Bt2 horizons) with a weighted average of 32 percent clay and 20 percent rock fragments.