LOCATION NORFORK                 NV

Established Series
Rev. PWB/CEJ/RLB
09/2019

NORFORK SERIES

The Norfork series consists of shallow, well drained soils that formed in loess with a component of volcanic ash and residuum and colluvium derived from basalt, andesite, rhyolite and metamorphic rocks. Norfork soils are on hill and mountain side slopes and tilted volcanic flows. Slopes are 2 to 30 percent. The mean annual precipitation is about 280 mm and the mean annual temperature is 8 degrees C.

TAXONOMIC CLASS: Clayey, smectitic, mesic, shallow Xeric Argidurids

TYPICAL PEDON: Norfork very gravelly silt loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is partially covered with 60 percent gravel.

A--0 to 5 cm; pale brown (10YR 6/3) very gravelly silt loam, dark brown (10YR 3/3) moist; strong very thin and thin platy structure; soft, very friable, moderately sticky and moderately plastic; few very fine roots; many very fine vesicular pores; 30 percent gravel and 20 percent cobbles; neutral (pH 7.2); abrupt smooth boundary. (5 to 10 cm thick)

Bt1--5 to 13 cm; pale brown (10YR 6/3) cobbly silty clay loam, brown (10YR 4/3) moist; moderate very fine subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; common very fine roots; common very fine tubular pores; common faint clay films on peds and in pores; 15 percent gravel and 15 percent cobbles; slightly alkaline (pH 7.4); clear wavy boundary. (5 to 13 cm thick)

Bt2--13 to 23 cm; light yellowish brown (10YR 6/4) gravelly silty clay, yellowish brown (10YR 5/4) moist; weak medium prismatic structure that parts to moderate fine and medium subangular blocky; hard, very friable, moderately sticky and very plastic; common very fine and few coarse roots; common very fine tubular pores; continuous faint clay films on peds and in pores; 30 percent gravel; slightly alkaline (pH 7.8); clear wavy boundary. (8 to 18 cm thick)

Bqk--23 to 30 cm; very pale brown (10YR 7/3) continuous weakly silica cemented gravelly silty clay loam, brown (10YR 5/3) moist; massive; hard, friable, moderately sticky and moderately plastic; few very fine roots; few very fine tubular pores; 10 percent 10 to 20 millimeter strong durinodes; 30 percent gravel; thin carbonate coatings on undersides of gravel; strongly effervescent; moderately alkaline (pH 8.4); abrupt wavy boundary. (0 to 10 cm thick)

Bqkm--30 to 61 cm; very pale brown (10YR 8/2) indurated duripan, very pale brown (10YR 7/3) moist; massive; extremely hard, extremely firm; continuous 1 to 2 mm thick horizontal silica laminae on upper surface and in alternating bands throughout the horizon; violently effervescent; strongly alkaline (pH 8.6); abrupt wavy boundary. (13 to 50 cm thick)

R--61 cm; fractured basalt bedrock with strongly silica and carbonate cemented material extending from the duripan into fractures.

TYPE LOCATION: Elko County, Nevada; about 15 miles northwest of Deeth, approximately 300 feet north and 1,200 feet west of the southeast corner of section 14, T. 39 N., R. 57 E.; USGS Double Mountain SE 7.5 minute topographic quadrangle; latitude 41 degrees 15 minutes 51 seconds N., and longitude 115 degrees 30 minutes 46 seconds W; WGS84 Decimal Degrees 41.2641667 latitude, -115.5127778 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, moist in the winter and spring, dry from late June through October; aridic soil moisture regime bordering on xeric.
Soil temperature: 8 to 10 degrees C.
Depth to base of Bt horizon: 18 to 36 cm.
Depth to indurated duripan: 25 to 50 cm.
Depth to bedrock: 53 to 100 cm.

Particle-size control section - Clay content: 35 to 45 percent.
Rock fragments: Averages 20 to 30 percent mainly gravel with up to 15 percent cobbles.

A horizon
Value: 5 or 6 dry.
Chroma: 2 or 3.
Structure: Platy or granular.
Consistence: Soft or slightly hard, very friable or friable, nonsticky to moderately sticky, nonplastic to moderately plastic.
Reaction: Neutral through slightly alkaline.

Bt horizons
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 3 or 4.
Texture: Gravelly silty clay, gravelly silty clay loam or cobbly silty clay loam.
Reaction: Neutral through moderately alkaline.

Bqk horizon (when present)
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 3 or 4.
Texture: Gravelly loam, gravelly silt loam or gravelly silty clay loam.
Rock fragments: 20 to 35 percent with as much as 5 percent cobbles.
Reaction: Slightly alkaline or moderately alkaline.

COMPETING SERIES: These are the Buffaran, Indian Creek and Midraw series. Buffaran and Indian Creek soils lack bedrock within 150 cm. Midraw soils are 36 to 50 cm to the base of the Bt horizons and have clay loam and clay textures in the argillic horizon.

GEOGRAPHIC SETTING: Norfork soils are on hill mountain side slopes and tilted volcanic flows. These soils formed in loess with a component of volcanic ash and residuum and colluvium derived from basalt, andesite, rhyolite and metamorphic rocks. Slopes are 2 to 30 percent. Elevations are 1,710 to 2,045 meters. The climate is cool, and semiarid with warm, dry summers and cool, moist winters. The mean annual precipitation is 200 to 300 mm; mean annual temperature is 7 to 9 degrees C, and the frost-free season is 100 to l20 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chiara soils. Chiara soils lack argillic horizons and bedrock within 150 cm.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; medium or rapid runoff; moderately low saturated hydraulic conductivity.

USE AND VEGETATION: Rangeland and wildlife habitat. The present vegetation is mainly black sagebrush, Douglas rabbitbrush, bottlebrush squirreltail, Sandberg bluegrass, bluebunch wheatgrass and cheatgrass.

DISTRIBUTION AND EXTENT: Northeastern and central Nevada. These soils are not extensive. MLRA 24, 25.

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

SERIES ESTABLISHED: Lander County, Nevada, North Part, 1985.

Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from 0 to 5 cm (A horizon).
Argillic horizon - The zone from about 5 to 23 cm (Bt horizons).
Xeric intergrades - Meet organic carbon requirement for xeric.
Indurated duripan - The zone from about 30 to 61 cm (Bqm horizon).
Lithic contact - The boundary at about 61 cm (R layer).
Particle-size control section - The zone from the soil surface to about 30 cm (A1, Bt1, Bt2 and Bqk horizons).

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National Cooperative Soil Survey
U.S.A.