LOCATION LETAVARIA NVTentative Series
TAXONOMIC CLASS: Fine, smectitic, frigid Pachic Palexerolls
TYPICAL PEDON: Letavaria gravelly loam, 4 to 15 percent slopes, rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is partly covered with 10 percent pebbles.
A--0 to 4 inches; very dark grayish brown (10YR 3/2) gravelly loam, black (10YR 2/1) moist; moderate thin platy structure parting to strong fine granular; soft, very friable, slightly sticky and slightly plastic; many very fine, fine and medium inped roots; many very fine interstitial pores; 15 percent pebbles; neutral (pH 7.0); abrupt wavy boundary. (2 to 5 inches thick)
Bt1--4 to 15 inches; dark grayish brown (10YR 4/2) gravelly clay, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure parting to strong fine granular; slightly hard, friable, very sticky and very plastic; many very fine, fine, medium and coarse inped roots; many very fine and few fine tubular pores; few thin clay films on faces of peds; 20 percent pebbles; neutral (pH 7.2); clear wavy boundary. (3 to 12 inches thick)
Bt2--15 to 22 inches; brown (10YR 5/3) gravelly clay, dark brown (10YR 3/3) moist; moderate coarse angular blocky structure; very hard, firm, very sticky and very plastic; common very fine and fine, few medium and coarse exped roots; many very fine and few fine tubular pores; many thin clay films on faces of peds and lining pores; 30 percent pebbles; neutral (pH 7.2); clear wavy boundary. (5 to 8 inches thick)
Bt3--22 to 27 inches; yellowish brown (10YR 5/4) gravelly clay, dark yellowish brown (10YR 4/4) moist; moderate coarse prismatic structure; very hard, firm, very sticky and very plastic; few very fine, fine and medium exped roots; many very fine, few fine tubular pores; many pressure faces; few moderately thick clay films lining pores; 30 percent pebbles; neutral (pH 7.2); abrupt wavy boundary. (4 to 7 inches thick)
Btk1--27 to 31 inches; very pale brown (10YR 7/3) gravelly clay, brown (10YR 5/3) moist; weak coarse prismatic structure parting to moderate medium subangular blocky hard, friable, very sticky and very plastic; few very fine, fine and medium inped roots; many very fine and few fine tubular pores; few stress surfaces; common fine rounded lime soft masses with lime coats on undersides of pebbles; 30 percent pebbles; violently effervescent; moderately alkaline (pH 8.2); abrupt wavy boundary. (3 to 6 inches thick)
Btk2--31 to 51 inches; light yellowish brown (2.5Y 6/4) gravelly clay, light olive brown (2.5Y 5/4) moist; parts to weak medium subangular blocky structure; hard, friable, very sticky and very plastic; few very fine, fine and medium inped roots; many very fine and few fine tubular pores; few stress surfaces; common fine, irregular soft lime filaments and many medium rounded lime soft masses with lime coats on undersides of pebbles; 30 percent pebbles; strongly effervescent in lime seams; moderately alkaline (pH 8.2); gradual wavy boundary. (15 to 25 inches thick)
2Bk--51 to 61 inches; light brownish gray (2.5Y 6/2) extremely gravelly sandy loam, light yellowish brown (2.5Y 6/4) moist; massive; hard, friable, slightly sticky and slightly plastic; few very fine roots; common very fine tubular pores; many medium rounded lime soft masses and lime filaments, common lime coats on rock fragments; 55 percent pebbles, 10 percent cobbles and 5 percent stones; violently effervescent; moderately alkaline (pH 8.4).
TYPE LOCATION: Elko County, Nevada; approximately 28 miles north of Wells; about 2,000 feet east and 750 feet south of the northwest corner of section 34, T. 42 N., R. 62 E., 41 degrees, 29 minutes, 29 seconds north latitude and 114 degrees, 56 minutes, 37 seconds west longitude.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually moist; dry from about mid-July to October.
Soil temperature - 44 to 46 degrees F.
Mollic epipedon thickness - 20 to 25 inches, includes the upper part of the argillic horizon.
Depth to argillic horizon - 2 to 5 inches.
Depth to calcic horizon - 24 to 30 inches.
Control section - Clay: 45 to 55 percent.
Rock fragments: 5 to 30 percent, mainly pebbles.
A horizon - Value: 3 or 4 dry, 2 or 3 moist.
Chroma: 2 or 3.
Bt horizon - Value: 4 or 5 dry, 3 or 4 moist.
Chroma: 2 or 3.
Textures: Gravelly clay or clay.
Structure: Angular blocky, subangular blocky or prismatic.
Btk horizon - Hue: 10YR or 2.5Y.
Value: 6 or 7 dry, 4 or 5 moist.
Calcium carbonate equivalent: 15 to 25 percent.
Textures: Gravelly clay or clay.
Bk horizon - Value: 6 or 7 dry, 4 through 6 moist.
Calcium carbonate equivalent: 20 to 40 percent.
COMPETING SERIES: These are the Goring, Greentimber, Prag and Skullgulch series. Goring and Greentimber soils are noncalcareous in all parts. In addition, Goring soils have slightly acid or neutral soil reaction and have argillic horizons with hue of 7.5YR or redder. Greentimber soils have buried Bt horizons that extend below 60 inches, have control sections with 35 to 45 percent clay and moderately acid or slightly acid soil reaction. Prag soils are moderately deep over partially consolidated sediments. Skullgulch soils have Bw horizons overlying the argillic, are 20 to 30 inches to the upper boundary of the argillic horizon and are more than 60 inches to the base of the argillic horizon.
GEOGRAPHIC SETTING:The Letavaria series is on fan piedmont remnants. Letavaria soils formed in alluvium from mixed rock sources. Elevations range from 6,400 to 6,800 feet. The climate is characterized by cold, moist winters and warm, dry summers. Mean annual precipitation is 10 to 14 inches; mean annual air temperature is 42 to 45 degrees; the frost-free season is 90 to 100 days. Slopes range from 4 to 15 percent.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cotant and Fenelon series. Cotant soils are shallow over bedrock. Fenelon soils are moderately deep and have fine-loamy control section textures.
DRAINAGE AND PERMEABILITY: Well drained; medium or rapid runoff; very slow permeability.
USE AND VEGETATION: Rangeland and wildlife habitat. The present vegetation is mainly serviceberry, Idaho fescue, bluebunch wheatgrass and antelope bitterbrush.
DISTRIBUTION AND EXTENT: Northeast Nevada, MLRA 25. This series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Elko County, Nevada, Northeast Part Soil Survey, 1991.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Pachic mollic epipedon - The zone from the soil surface to about 22 inches ( The A, Bt1 and Bt2 horizons).
Argillic horizon - The zone from about 4 to 51 inches ( The Bt1, Bt2, Bt3, Btk1 and Btk2 horizons).
There is a 20 percent increase in clay within a vertical distance of 1 inch between 4 inches and 5 inches (the boundary between the A and Bt1 horizons).
Particle-size control section - The zone from 4 to 24 inches (The Bt1, Bt2 and part of the Bt3 horizon).