LOCATION HORNING                 OR

Established Series
Rev. JVC-JBF
03/2011

HORNING SERIES

The Horning series consists of very deep, somewhat excessively drained soils that formed in eolian material derived from volcanic ash and diatomite over lacustrine deposits derived from diatomite and tuff. Horning soils are on stable dunes on lake terraces. Slopes are 0 to 20 percent. The mean annual precipitation is about 230 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Ashy, glassy, calcareous, frigid Vitrandic Torriorthents

TYPICAL PEDON: Horning ashy loamy sand--on a convex, south-facing slope of 2 percent under basin big sagebrush and black greasewood at an elevation of 1,314 meters--rangeland. (Colors are for dry soil unless otherwise noted. When described on August 25, 1994, the soil was dry throughout.)

A--0 to 10 cm; light brownish gray (10YR 6/2) ashy loamy sand, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky and nonplastic; many very fine, many fine, and few medium roots; many very fine interstitial and few fine tubular pores; 30 percent very pale brown (10YR 8/2) diatomite sand grains (0.1 to 0.5 mm diameter); moderately alkaline (pH 8.0); clear smooth boundary. (8 to 25 cm thick)

Bkn--10 to 66 cm; light brownish gray (10YR 6/2) ashy loamy fine sand, dark brown (10YR 3/3) moist; weak fine subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky and nonplastic; many very fine and fine roots, few medium; common fine interstitial pores; 30 percent very pale brown (10YR 8/2) diatomite sand grains (0.1 to 0.5 mm diameter); secondary carbonates are disseminated in the matrix; slightly effervescent; strongly alkaline (pH 9.0); clear smooth boundary.

Bknb--66 to 102 cm; light brownish gray (10YR 6/2) ashy fine sandy loam, dark brown (10YR 3/3) moist; weak fine and medium subangular blocky structure; soft, friable, nonsticky and nonplastic; common very fine and common fine roots; common fine tubular pores; 30 percent very pale brown (10YR 8/2) diatomite sand grains (0.1 to 0.5 mm diameter); secondary carbonates are disseminated in the matrix; slightly effervescent; very strongly alkaline (pH 9.5); clear smooth boundary.

Bkb1--102 to 122 cm; light gray (10YR 7/2) ashy loamy fine sand, brown (10YR 5/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine, common fine, and few medium roots; many fine interstitial pores; 50 percent very pale brown (10YR 8/2) diatomite sand grains (0.1 to 0.5 mm diameter); secondary carbonates are disseminated in the matrix; strongly effervescent; moderately alkaline (pH 8.4); clear wavy boundary.

Bkb2--122 to 147 cm; light gray (10YR 7/2) ashy loamy sand, brown (10YR 5/3) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine, common fine, and few medium roots; few fine tubular pores; 10 percent very pale brown (10YR 8/2) diatomite sand grains (0.1 to 0.5 mm diameter); secondary carbonates are disseminated in the matrix; strongly effervescent; strongly alkaline (pH 8.6); abrupt smooth boundary. (Combined thickness of the Bkn and Bk horizons is 76 to 150 cm)

2C1--147 to 178 cm; very pale brown (10YR 7/3) ashy fine sandy loam, brown (10YR 4/3) moist; massive; soft, friable, nonsticky and nonplastic; common very fine and common fine roots; few fine tubular pores; violently effervescent; very strongly alkaline (pH 10.3); clear smooth boundary.

2C2--178 to 216 cm; very pale brown (10YR 7/3) ashy loam, brown (10YR 4/3) moist; massive; slightly hard, friable, nonsticky and nonplastic; few very fine and few fine roots; few fine tubular pores; violently effervescent; very strongly alkaline (pH 9.4).

TYPE LOCATION: Lake County, Oregon; in the southeastern part of Fort Rock Valley; approximately 2,600 feet south and 1,700 feet west of the northeast corner of section 15, T. 27 S., R. 16 E.; USGS Thorn Lake 7.5 minute topographic quadrangle; latitude 43 degrees 13 minutes 43 seconds N and longitude 120 degrees 48 minutes 35 seconds W; NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Moist in the moisture control section in winter and spring.; aridic (torric) moisture regime that borders on xeric.
Mean annual soil temperature: 7 to 8 degrees C.
Ochric epipedon thickness: 8 to 25 cm.
Depth to identifiable secondary carbonates: 8 to 25 cm.
Depth to buried horizons: 64 to 100 cm.
Depth to bedrock: More than 152 cm to a paralithic contact.
Volcanic glass content: 30 to 70 percent in coarse silt through fine sand fractions.
Other features: Diatomite grains may comprise up to 50 percent of the sand fraction in some horizons.

Particle-size control section - Clay content: Averages 4 to 10 percent;

A horizon
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Salinity (EC): 2 to 4 mmhos/cm.
Sodicity (SAR): 1 to 13.

Bkn horizon
Value: 5 through 7 dry, 3 through 5 moist.
Chroma: 2 or 3, dry or moist.
Texture: Ashy loamy sand, ashy loamy fine sand, or ashy sand.
Clay content: 2 to 10 percent.
Reaction: Moderately alkaline or strongly alkaline.
Salinity (EC): 4 to 16 mmhos/cm.
Sodicity (SAR): 13 to 30.
Effervescence: Slightly effervescent or strongly effervescent.
Identifiable secondary carbonates: Occurs as finely disseminated crystals in the matrix or as coats on coarse sand grains.
Calcium carbonate equivalent: 1 to 8 percent.

Bknb horizon
Value: 5 through 7 dry, 3 through 5 moist.
Chroma: 2 or 3, dry or moist.
Texture: Ashy fine sandy loam or ashy sandy loam.
Clay content: 5 to 10 percent.
Reaction: Moderately alkaline to very strongly alkaline (up to pH 9.6).
Salinity (EC): 4 to 16 mmhos/cm.
Sodicity (SAR): 30 to 90.
Effervescence: Slightly effervescent or strongly effervescent.
Identifiable secondary carbonates: Occurs as finely disseminated crystals in the matrix or as coats on coarse sand grains.
Calcium carbonate equivalent: 1 to 8 percent.

Bkb horizons
Value: 5 through 7 dry, 3 through 5 moist.
Chroma: 2 or 3, dry or moist.
Texture: Ashy loamy fine sand or ashy loamy sand.
Clay content: 5 to 10 percent.
Reaction: Moderately alkaline or strongly alkaline.
Salinity (EC): 2 to 16 mmhos/cm.
Sodicity (SAR): 5 to 30.
Effervescence: Slightly effervescent or strongly effervescent.
Identifiable secondary carbonates: Occurs as finely disseminated crystals in the matrix or as coats on coarse sand grains.
Calcium carbonate equivalent: 1 to 8 percent.

2C horizons
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 2 or 3, dry or moist.
Texture: Ashy loam, ashy fine sandy loam, or ashy silt loam.
Clay content: 10 to 25 percent.
Rock fragment content: 0 to 5 percent fine gravel
Reaction: Strongly alkaline or very strongly alkaline (up to pH 11.0).
Salinity (EC): 8 to 32 mmhos/cm.
Sodicity (SAR): 30 to 150.
Calcium carbonate equivalent: 5 to 15 percent.

COMPETING SERIES: There are currently no other series in this family.

GEOGRAPHIC SETTING: Horning soils are on stable dunes on lake terraces. They formed in eolian material derived from volcanic ash and diatomite over lacustrine deposits derived from diatomite and tuff. The source of the volcanic ash is ancestral Mt. Mazama. Slopes are 0 to 20 percent. Elevations range from 1,304 to 1,378 meters. The climate is semiarid and characterized by cold, moist winters and warm, dry summers. The mean annual precipitation is 200 to 250 mm, the mean annual temperature is 6 to 7 degrees C, and the frost-free period is 50 to 80 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Abert, Morehouse, Tonor, and Youtlkue soils. Abert and Tonor soils are ashy, have cambic horizons, and are on summit positions of lake terraces. Morehouse soils are ashy, do not have loamy textures within the particle-size control section, do not have identifiable secondary carbonates or sodium adsorption ratios greater than 13 within 100 cm of the soil surface, and are on stable dunes. Youtlkue soils are ashy, moderately deep to paralithic contacts, have cambic horizons, and are in depressions on lake terraces.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat excessively drained; very low surface runoff; moderately high saturated hydraulic conductivity.

USE AND VEGETATION: Horning soils are used for livestock grazing and wildlife habitat. Potential native vegetation is basin big sagebrush, spiny hopsage, black greasewood, and creeping wildrye.

DISTRIBUTION AND EXTENT: South-central Oregon. These soils are not extensive with about 4,700 acres of the series mapped to date. MLRA 23.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.

SERIES ESTABLISHED: Lake County (Northern Part), Oregon, 2006. The series was first proposed in Lake County, Oregon in 1961.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 18 cm (A horizon and part of Bkn horizon).
Identifiable secondary carbonates - The zone from 10 to 147 cm (Bkn, Bknb, Bkb1, and Bkb2 horizons).
Vitrandic intergrade feature - The zone from the soil surface to 76 cm (A and Bkn horizons and part of the Bknb horizon).
Entisol feature - Subsoil textures above the buried horizons are too coarse for a cambic horizon.
Buried horizons - The zone from 66 to 147 cm (Bknb, Bkb1, and Bkb2 horizons).
Particle-size control section and ashy substitute class with glassy mineralogy - The zone from 25 to 100 cm (Bknb horizon and part of the Bkn horizon).

The revision of April 2001 updated the taxonomic class from Mixed, frigid Xeric Torripsamments. The ashy substitute class, glassy mineralogy class, and volcanic glass content are estimated based on properties of adjacent soils.

ADDITIONAL DATA: The typical pedon at the series type location is reference sampled for the Soil Survey Laboratory (SSL), Lincoln, NE, as soil survey sample number S94OR-037-003 (pedon # 95P0059). Selected data are available for the horizons from 4-26, 26-40, 40-48, and 58-70 inches.

Former editors and authors include: RPM-GJW-TDT.

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National Cooperative Soil Survey
U.S.A.