LOCATION TRUNK NVEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Xeric Haplargids
TYPICAL PEDON: Trunk stony loam, rangeland. (Colors are for dry soil unless otherwise noted).
A--0 to 3 inches; light brownish gray (10YR 6/2) stony loam, dark grayish brown (10YR 4/2) moist; moderate fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine interstitial pores; 1 percent stones, 2 percent cobbles, 25 percent pebbles; neutral (pH 7.0); clear smooth boundary. (3 to 6 inches thick)
Bt--3 to 12 inches; yellowish brown (10YR 5/4) gravelly clay, dark yellowish brown (10YR 4/4) moist; weak fine prismatic structure parting to strong very fine subangular blocky; very hard, firm, sticky and plastic; common very fine, few fine and medium roots; common very fine and fine tubular pores; many thin and few moderately thick clay films on peds and in pores; 15 percent pebbles; neutral (pH 7.0); clear wavy boundary. (6 to 12 inches thick)
Btk1--12 to 20 inches; light yellowish brown (10YR 6/4) gravelly clay, yellowish brown (10YR 5/4) moist; moderate fine subangular blocky structure; very hard, firm, sticky and plastic; few very fine and fine roots; common very fine and fine tubular pores; few moderately thick clay films lining pores; 25 percent pebbles; many fine distinct white (10YR 8/2) soft lime masses; violently effervescent; moderately alkaline (pH 8.4); clear wavy boundary. (6 to 12 inches thick)
Btk2--20 to 30 inches; light yellowish brown (10YR 6/4) very gravelly clay loam, yellowish brown (10YR 5/4) moist; moderate fine subangular blocky structure; very hard, firm, sticky and plastic; few very fine roots; common very fine and few fine tubular pores; common moderately thick clay films lining pores; 35 percent pebbles; may fine distinct white (10YR 8/2) soft lime masses; violently effervescent; moderately alkaline (pH 8.4); abrupt irregular boundary. (6 to 12 inches thick)
2R--30 inches; fractured quartzite; weathered pockets can be dug with hand tools; bedrock lime coats and clay coats along fractures.
TYPE LOCATION: Pershing County, Nevada; approximately 20 miles south of Winnemucca, about 1,000 feet north and 1,000 feet west of the southeast corner of section 11, T. 33 N., R. 38 E.
RANGE IN CHARACTERISTICS: Soil moisture - Usually dry, moist in the late fall, winter and early spring months, dry late May through October.
Soil temperature - 47 to 53 degrees.
Depth to bedrock - 20 to 40 inches.
Depth to lime - 10 to 20 inches.
A horizon - Value: 5 or 6 dry, 3 through 5 moist.
Chroma: 2 or 3.
Reaction: Neutral to mildly alkaline.
Bt horizons - Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 3 through 5.
Texture: Gravelly clay loam or gravelly clay with more than 30 percent sand.
Clay content: 35 to 50 percent.
Rock fragments: 15 to 35 percent, mainly pebbles.
Reaction: Neutral to mildly alkaline in noncalcareous upper sub horizon, moderately to strongly alkaline in calcareous lower subhorizon.
Consistence: Slightly hard to very hard, dry; friable or firm, moist.
Carbonates: Noneffervescent in the upper part; lower part is slightly effervescent to violently effervescent with segregated lime as soft masses, filaments or coatings on rock fragments.
COMPETING SERIES: These are the Buncelvoir(T)(ID), Diaz(T)(CA), Dryvalley(T)(CA), Farmell (OR), Glasgow (OR), Lanktree (ID), Linkletter(T)(ID), Oppio (NV), Risley (NV), and Schamp (CA) series. Buncelvoir, Dryvalley, Farmell, Lanktree, and Schamp soils are very deep. Diaz soils have mildly to moderately alkaline A horizons, argillic horizons of silty clay or clay with less than 30 percent sand and lack rock fragments. Glasgow soils have 6 to 16 inch A horizons of loess and have argillic horizons with less than 15 percent rock fragments. Linkletter soils are 40 to 60 inches deep to a duripan and are greater than 60 inches to bedrock. Oppio soils lack secondary lime. Risley soils have less than 15 percent rock fragments in the argillic horizon and have a paralithic contact at a depth of 20 to 40 inches.
GEOGRAPHIC SETTING: Trunk soils are on sideslopes of plateaus and fan piedmonts with a rock core, and convex mountain and foothill crests and side slopes. These soils formed in residuum and colluvium from andesite, rhyolite, quartzite, chert, sandstone, shale, slate and argillite. Slopes are 4 to 50 percent. Elevations are 4,500 to 6,500 feet. The climate is cool, semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 8 to 10 inches; mean annual temperature is 45 to 50 degrees F., and the frost-free season is 100 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Burrita, Golsum and Pocan soils. Burrita soils have a lithic contact within 20 inches and a clayey-skeletal control section. Golsum soils have an average annual soil temperature colder than 47 degrees F. Pocan soils lack bedrock within a depth of 40 inches.
DRAINAGE AND PERMEABILITY: Well drained; medium or rapid runoff; very slow permeability.
USE AND VEGETATION: Rangeland and wildlife habitat. The present vegetation is mainly Wyoming big sagebrush, bottlebrush squirreltail, rabbitbrush, horsebrush, cheatgrass and ephedra.
DISTRIBUTION AND EXTENT: North-central Nevada. MLRA 24. These soils are moderately extensive.
MLRA OFFICE RESPONSIBLE: Reno, Nevada
SERIES ESTABLISHED: Pershing County (BLM Sonoma Planning Unit), Nevada. 1974.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Argillic horizon - The zone from 3 to 30 inches (Bt, Btk1 and Btk2 horizons).
Xerollic intergrade - Meets organic carbon requirement for "Xerollic".
Lithic contact - The boundary at about 30 inches (2R horizon).
Particle-size control section - The zone from about 3 to 23 inches (Bt and Btk1 horizons and part of the Btk2 horizon).