LOCATION ECUR IDEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Sodic Xeric Haplocalcids
TYPICAL PEDON: Ecur fine sandy loam--on a 3 percent slope at 4,755 feet elevation--rangeland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 2 inches; light brownish gray (10YR 6/2) fine sandy loam, dark grayish brown (10YR 4/2) moist; moderate very coarse platy structure; soft, very friable, slightly sticky and slightly plastic; few very fine roots; many very fine vesicular and common very fine tubular pores; slightly effervescent; less than 5 percent fine gravel; moderately alkaline (pH 8.1); abrupt smooth boundary.
A2--2 to 6 inches; light brownish gray (10YR 6/2) fine sandy loam, dark grayish brown (10YR 4/2) moist; weak medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and few fine roots; common very fine tubular pores; slightly effervescent; less than 5 percent fine gravel; moderately alkaline (pH 8.2); abrupt smooth boundary. (Combined thickness of the A horizons is 3 to 6 inches)
Bw--6 to 15 inches; light brownish gray (10YR 6/2) fine sandy loam, grayish brown (10YR 5/2) moist; weak medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and medium and few fine roots; common very fine tubular pores; strongly effervescent; 5 to 10 percent rounded nodules; 5 percent gravel; moderately alkaline (pH 8.2); abrupt wavy boundary. (7 to 24 inches thick)
Bkn1--15 to 27 inches; light gray (2.5Y 7/2) fine sandy loam, grayish brown (2.5Y 5/2) moist; massive; hard, firm, slightly sticky and slightly plastic; few very fine roots; few very fine tubular pores; few fine veins of secondary carbonate that are very pale brown (10YR 8/2) dry and light gray (10YR 7/2) moist; violently effervescent; 5 percent gravel; strongly alkaline (pH 8.6); abrupt wavy boundary.
Bkn2--27 to 37 inches; light gray (2.5Y 7/2) fine sandy loam, grayish brown (2.5Y 5/2) moist; massive; slightly hard, friable, nonsticky and nonplastic; few very fine and fine roots; few very fine tubular pores; violently effervescent; 5 percent gravel; strongly alkaline (pH 8.6); clear wavy boundary. (Combined thickness of the Bkn horizons is 15 to 30 inches)
Cn1--37 to 44 inches; light gray (2.5Y 7/2) loamy fine sand, grayish brown (2.5Y 5/2) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine and common medium roots; few very fine tubular pores; strongly effervescent; 15 percent rounded nodules; 5 percent gravel; strongly alkaline (pH 8.5); clear wavy boundary. (5 to 15 inches thick)
Cn2--44 to 49 inches; pale yellow (2.5Y 8/2) gravelly loamy fine sand, grayish brown (2.5Y 5/2) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine and common medium roots; few very fine tubular pores; strongly effervescent; 15 percent rounded nodules; 20 percent gravel; strongly alkaline (pH 8.6); clear wavy boundary. (0 to 15 inches thick)
Cn3--49 to 60 inches; pale yellow (2.5Y 8/2) loamy fine sand, light brownish gray (2.5Y 6/2) moist; massive; slightly hard, friable, nonsticky and nonplastic; few very fine roots; few very fine tubular pores; strongly effervescent; less than 2 percent gravel; strongly alkaline (pH 8.6).
TYPE LOCATION: Oneida County, Idaho; about 5 miles south of Juniper; approximately 2,640 feet south and 450 feet west of the northeast corner of section 33, T. 15 S., R. 30 E.; USGS Black Pine 7.5 minute topographic quadrangle; 42 degrees 04 minutes 31 seconds north latitude and 112 degrees 56 minutes 53 seconds west longitude, NAD83.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 48 to 50 degrees F.
Depth to calcic horizon - 10 to 30 inches.
Particle-size control section - Clay content: Averages 5 to 15 percent;
Rock fragments: Averages 0 to 10 percent.
A horizons
Value: 3 or 4 moist.
Rock fragments: 0 to 5 percent.
Calcium carbonate equivalent: 20 to 35 percent.
Sodicity (SAR): 0 to 8.
Bw horizon
Value: 4 or 5 moist.
Chroma: 2 or 3, dry or moist.
Texture: Fine sandy loam or loam.
Rock fragments: 0 to 10 percent.
Calcium carbonate equivalent: 25 to 35 percent.
Sodicity (SAR): 0 to 13.
Bkn horizons
Hue: 10YR or 2.5Y.
Value: 5 or 6 moist.
Chroma: 2 or 3, dry or moist.
Texture: Fine sandy loam or loam.
Rock fragments: 0 to 10 percent.
Reaction: Moderately alkaline through very strongly alkaline.
Calcium carbonate equivalent: 30 to 45 percent.
Sodicity (SAR): 13 to 30.
Cn horizons
Hue: 10YR or 2.5Y.
Value: 7 or 8 dry, 5 or 6 moist.
Chroma: 2 or 3, dry or moist.
Texture: Loamy fine sand or gravelly loamy fine sand.
Rock fragments: 0 to 25 percent.
Reaction: Moderately alkaline or strongly alkaline.
Calcium carbonate equivalent: 20 to 35 percent.
Sodicity (SAR): 13 to 30.
COMPETING SERIES: There are currently no other series in this family.
GEOGRAPHIC SETTING: Ecur soils are on lake terraces and fan remnants. They formed in alluvium and lacustrine deposits with some loess influence. Slopes are 0 to 30 percent. Elevation ranges from 4,400 to 5,000 feet. The mean annual precipitation is 11 to 13 inches and the mean annual air temperature is 46 to 48 degrees F. The frost-free period is 100 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bayhook, Darkbull, and Pyrat soils. Bayhook soils are on concave slopes lower on the landscape than Ecur soils and are coarse-silty. Darkbull soils are on similar to slightly convex slopes as Ecur soils, are loamy-skeletal, and have a low sodium adsorption ratio. Pyrat soils are on convex slopes above Ecur soils and are loamy-skeletal.
DRAINAGE AND PERMEABILITY: Well drained; very low or low surface runoff; moderately rapid permeability (high saturated hydraulic conductivity).
USE AND VEGETATION: Ecur soils are used mainly as rangeland and minor acreages for irrigated cropland. The potential natural vegetation includes basin big sagebrush and bluebunch wheatgrass. Irrigated crops are small grains.
DISTRIBUTION AND EXTENT: Southeastern Idaho. These soils are not extensive with about 8,700 acres of the series mapped to date. MLRA 28A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona.
SERIES ESTABLISHED: Oneida County, Idaho, 1994. The name is coined from Curlew Valley.
REMARKS: Diagnostic features and horizons recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 6 inches (A1 and A2 horizons).
Cambic horizon - The zone from 6 to 15 inches (Bw horizon).
Calcic horizon - The zone from 15 to 37 inches (Bkn1 and Bkn2 horizons).
Sodic feature - The zone from 15 to 40 inches (Bkn1 and Bkn2 horizons and part of the Cn1 horizon).
Particle-size control section - The zone from 10 to 40 inches (Bkn1 and Bkn2 horizons and parts of the Bw and Cn1 horizons).
These soils were previously a part of the Eccles series. The Eccles series has since been reclassified as Inceptisols. The superactive cation exchange activity class was added in 03/2003 to the taxonomic classification by the National Soil Survey Center on request of the Reno MLRA office, without review of the soil series property data.