LOCATION LAVEY OREstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Calciargidic Argixerolls
TYPICAL PEDON: Lavey gravelly silt loam - on a gentle slope, rangeland. (Colors are for moist soil unless otherwise noted.)
A--0 to 5 inches; dark brown (10YR 3/2) gravelly silt loam, grayish brown (10YR 5/2) dry; weak medium platy structure parting to weak fine granular; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; common very fine and fine irregular pores; 20 percent gravel; neutral (pH 7.0); clear smooth boundary. (3 to 10 inches thick)
Bt1--5 to 12 inches; dark brown (10YR 3/3) silty clay loam, brown (10YR 5/3) dry; moderate fine and medium subangular blocky structure; hard, firm, sticky and plastic; common very fine, fine and medium roots; common very fine and fine tubular pores; many faint clay films on faces of peds and lining pores; 5 percent gravel; mildly alkaline (pH 7.4); clear smooth boundary.
Bt2--12 to 21 inches; dark grayish brown (10YR 4/2) clay, pale brown (10YR 6/3) dry; strong medium and coarse subangular blocky structure; very hard, very firm, very sticky and very plastic; few very fine, fine and medium roots; few very fine and fine tubular pores; many prominent clay films on faces of peds and lining pores; 10 percent gravel; mildly alkaline (pH 7.0); clear wavy boundary. (combined thickness of the Bt horizon is 13 to 26 inches)
Btk--21 to 25 inches; dark grayish brown (10YR 4/2) silty clay loam, pale brown (10YR 6/3) dry; moderate fine and medium subangular blocky structure; hard, firm, sticky and plastic; few very fine and fine roots; few very fine and fine tubular pores; common faint clay films on faces of peds and lining pores; slightly effervescent with segregated lime in soft 1.0mm to 2.0mm masses; moderately alkaline (pH 8.0); abrupt wavy boundary. (3 to 8 inches thick)
2Crkq--25 to 28 inches; paralithic tuff with silica and calcium carbonate coatings; strongly effervescent with disseminated lime (3 to 8 inches thick).
2R--28 inches; welded tuff of the Deschutes Formation. (See Remarks)
TYPE LOCATION: Jefferson County, Oregon, about 100 feet east and 300 feet north of the SW corner of section 25, T.9 S., R.12 E. (Latitude 44 degrees, 45 minutes, 12 seconds N, Longitude 121 degrees, 15 minutes, 18 seconds W) Warm Springs Indian Reservation.
RANGE OF CHARACTERISTICS: These soils are usually dry and are dry in all parts of the moisture control section for 120 to 150 days (cumulative) after the summer solstice. The mean annual soil temperature is 52 to 54 degrees F. Depth to bedrock of the Deschutes Formation is 20 to 40 inches. The mollic epipedon is 10 to 15 inches thick and may include the upper part of the argillic horizon. Depth to secondary carbonates is 20 to 36 inches. The particle-size control section averages 35 to 45 percent clay.
The A horizon has value of 2 or 3 moist, 4 or 5 dry and chroma of 2 or 3 moist and dry . It is silt loam or silty clay loam and contains 15 to 30 percent gravel and 0 to 40 percent cobbles.
The Bt horizon has value of 3 or 4 moist, 5 or 6 dry and chroma of 2 or 3 moist and dry. It is silty clay loam or clay and contains 5 to 15 percent gravel and 0 to 5 percent cobbles. It is neutral to mildly alkaline.
The Btk horizon has hue of 10YR but may range to 5YR. It has value of 4 or 5 moist, 5 or 6 dry and chroma of 2 to 4 moist and dry. It is silty clay loam or clay and contains 0 to 10 percent gravel.
The 2Crkq horizon is paralithic tuff or water laid sediments of the Deschutes Formation. It is strongly to violently effervescent.
COMPETING SERIES: These are the Arzo, Encina, Kanarra (T) and Krebs series. Arzo soils lack a 2Crkq horizon over a lithic bedrock. Encina soils are greater than 60 inches to bedrock and are dry for more than 80 consecutive days. Kanarra sols are greater than 60 inches to bedrock and are dry for 45 to 70 consecutive days. Krebs soils are 40 to 60 inches to bedrock and are dry for more than 80 consecutive days.
GEOGRAPHIC SETTING: Lavey soils are on gently sloping to strongly sloping upland terraces. The soil formed in loess and colluvium over sedimentary rock or tuff. Slopes are 2 to 15 percent. Elevations are 1400 to 2400 feet. The climate is characterized by cool and moist winters and hot and dry summers. The mean annual precipitation is 9 to 12 inches. The mean annual temperature is 50 to 52 degrees F. The frost-free period is 110 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Antoken, Day, Madras, Simas, and Skoven soils. Antoken soils are on north-facing foot slopes, clayey-skeletal and very deep to bedrock. Day soils are on foothills, very-fine, and very deep to sedimentary bedrock. Madras soils are on adjacent terraces, fine-loamy and moderately deep to bedrock. Simas soils are on adjacent foothills, and very deep to sedimentary bedrock. Skoven soils are on upland terraces, clayey-skeletal, and shallow to volcanic tuff.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is slow.
USE AND VEGETATION: These soils are used for livestock grazing and wildlife habitat. The native vegetation is basin big sagebrush, bluebunch wheatgrass and Sandberg bluegrass.
DISTRIBUTION AND EXTENT: North-central Oregon; MLRA 10. The soils of this series are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Jefferson County (Warm Springs Indian Reservation), Oregon, 1993.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from the surface of the soil to a depth of approximately 12 inches ( A and Bt1 horizons).
Aridic moisture regime more than 120 dry days.
Argillic horizon - the zone from 5 to 25 inches (Bt1 and Bt2 horizons).
Calcic feature - the zone from 21 to 25 inches (Btk horizon).
Deschutes Formation - semiconsolidated water-laid sediments composed of sands, gravels, and silts of volcanic origin, and reworked volcanic materials. Interbedded basalts and ash-flow tuffs are included in this formation.