LOCATION NORFORK NVEstablished Series
TAXONOMIC CLASS: Clayey, smectitic, mesic, shallow Xeric Argidurids
TYPICAL PEDON: Norfork very cobbly silt loam, rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is partially covered with 60 percent pebbles.
A--0 to 2 inches; pale brown (10YR 6/3) very cobbly silt loam, dark brown (10YR 3/3) moist; strong very thin and thin platy structure; soft, very friable, sticky and plastic; few very fine roots; many very fine vesicular pores; 30 percent pebbles and 20 percent cobbles; neutral (pH 7.2); abrupt smooth boundary. (2 to 4 inches thick)
Bt1--2 to 5 inches; pale brown (10YR 6/3) cobbly silty clay loam, brown (10YR 4/3) moist; moderate very fine subangular blocky structure; slightly hard, very friable, sticky and plastic; common very fine roots; common very fine tubular pores; common thin clay films on peds and in pores; 15 percent pebbles and 15 percent cobbles; mildly alkaline (pH 7.4); clear wavy boundary. (2 to 5 inches thick)
Bt2--5 to 9 inches; light yellowish brown (10YR 6/4) gravelly silty clay, yellowish brown (10YR 5/4) moist; weak moderate prismatic structure that parts to moderate fine and medium subangular blocky; hard, very friable, sticky and very plastic; common very fine and few coarse roots; common very fine tubular pores; continuous thin clay films on peds and in pores; 30 percent pebbles; mildly alkaline (pH 7.8); clear wavy boundary. (3 to 7 inches thick)
Bqk--9 to 12 inches; very pale brown (10YR 7/3) continuous weakly silica cemented gravelly silty clay loam, brown (10YR 5/3) moist; massive; hard, friable, sticky and plastic; few very fine roots; few very fine tubular pores; 10 percent 10 to 20 millimeter strong durinodes; 30 percent pebbles; thin lime coatings on undersides of pebbles; strongly effervescent; moderately alkaline (pH 8.4); abrupt wavy boundary. (0 to 4 inches thick)
Bqkm--12 to 24 inches; white (10YR 8/2) indurated duripan, very pale brown (10YR 7/3) moist; massive; extremely hard, extremely firm; continuous 1 to 2 millimeters thick horizontal silica lamanae on upper surface and in alternating band throughout the horizon; violently effervescent; strongly alkaline (pH 8.6); abrupt wavy boundary. (5 to 20 inches thick)
R--24 inches; fractured basalt bedrock with strongly silica and lime 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.; 41 degrees, 15 minutes, 52 seconds north latitude, 115 degrees, 30 minutes, 43 seconds west longitude.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually dry, moist in the winter and spring, dry from late June through October.
Soil temperature - 47 to 52 degrees F.
Depth to base of Bt horizon - 7 to 14 inches.
Depth to indurated duripan - 10 to 20 inches.
Depth to bedrock - 21 to 40 inches.
Control section - Clay content: 35 to 45 percent.
Rock fragments: Averages 20 to 30 percent mainly pebbles 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 sticky, nonplastic to plastic.
Reaction: Neutral through 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: Mildly alkaline or moderately alkaline.
COMPETING SERIES: These are the Buffaran, Indian Creek and Midraw series. Buffaran and Indian Creek soils lack bedrock within 60 inches. Midraw soils are 14 to 20 inches 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 from basalt, andesite, rhyolite and metamorphic rocks. Slopes are 2 to 30 percent. Elevations are 5,600 to 6,700 feet. The climate is cool, and semiarid with warm, dry summers and cool, moist winters. The mean annual precipitation is 8 to l2 inches; mean annual temperature is 45 to 48 degrees F., 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 60 inches.
DRAINAGE AND PERMEABILITY: Well drained; medium or rapid runoff; slow permeability.
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 OFFICE RESPONSIBLE: Reno, Nevada
SERIES ESTABLISHED: Lander County, Nevada, North Part, 1985.
Diagnostic horizons and features recognized in this pedon are:
Argillic horizon - The zone from about 2 to 9 inches (Bt horizons).
Xerollic intergrades - Meet organic carbon requirement for "Xerollic".
Indurated duripan - The zone from about 12 to 24 inches (Bqm horizon).
Lithic contact - The boundary at about 24 inches (R horizon).
Particle-size control section - The zone from the soil surface to about 12 inches (A1, Bt1, Bt2 and Bqk horizons).