LOCATION HOLBORN NVEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive, calcareous, mesic, shallow Xeric Torriorthents
TYPICAL PEDON: Holborn gravelly loam, rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is partially covered with 25 percent pebbles.
A1--0 to 1 inches; pale brown (10YR 6/3) gravelly loam, brown (10YR 4/3) moist, weak thin platy structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; many very fine, common fine and few medium tubular pores; 30 percent pebbles; strongly effervescent; strongly alkaline (pH 8.5); abrupt wavy boundary. (1 to 3 inches thick)
A2--1 to 3 inches; brown (10YR 5/3) gravelly loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; soft, friable, sticky and plastic; many very fine, common fine and few medium roots; common very fine and few fine tubular pores; 15 percent pebbles; strongly effervescent; strongly alkaline (pH 8.5); clear wavy boundary. (0 to 3 inches thick)
Bk--3 to 7 inches; brown (10YR 5/3) gravelly loam, dark brown (10YR 4/3) moist; massive; slightly hard, friable, sticky and plastic; common fine and very fine, and few medium roots; common very fine and few fine tubular pores; 25 percent pebbles; thin lime coats on undersides; violently effervescent; strongly alkaline (pH 8.5); abrupt wavy boundary. (3 to 6 inches thick)
Cr--7 to 13 inches; soft weathered sandstone.
TYPE LOCATION: Elko County, Nevada; approximately 7 miles west of Montello, about 2,500 feet west and 2,600 feet south of the northeast corner, sec. 5, T. 39 N., R. 68 E.; 41 degrees, 17 minutes, 45 seconds north latitude and 114 degrees, 18 minutes, 19 seconds east longitude.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually dry, moist in winter and spring, dry June through October.
Soil temperature - 47 to 52 degrees F.
Depth to paralithic contact - 6 to 10 inches.
Control section - Clay content: Averages 18 to 30 percent.
Rock fragments: 15 to 35 percent, mainly pebbles.
Reaction: Moderately alkaline or strongly alkaline.
Calcium carbonate equivalent - Averages 5 to 30 percent.
Effervescence - Strongly effervescent or violently effervescent.
A horizon - Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3.
Other features: Combined thickness of the A horizon is 2 to 6 inches.
Bk horizons - Hue: 2.5YR or 10YR.
Value: 5 through 7 dry, 4 through 6 moist.
Chroma: 3 or 4.
Texture: Gravelly loam, gravelly clay loam.
COMPETING SERIES: These are the Coppereid (NV), Foxcan (NV), Grina (NV), Hundraw (NV), Jacratz (T NV), Puett (NV), Tert (NV) and Whilphang (NV) series. Coppereid, Hundraw and Puett soils have 10 to 18 percent clay in their particle-size section. Foxcan soils contain less than 18 percent clay in the particle size control section. Grina soils are 14 to 20 inches to a paralithic contact and lack Bk horizons with segregated lime. Jacratz soils are noneffervescent or slightly effervescent A horizons and contain more than 20 percent soft platy gravel in their control section. Tert and Whilphang soils have mean annual soil temperatures of 54 to 59 degrees F; Tert soils also lack Bk horizons and Whilphang soils have 10 to 18 percent clay in their control section.
GEOGRAPHIC SETTING: Holborn soils are on hills and rock piedmont remnants. These soils formed in residuum and colluvium weathered from tuff, sandstone and other similar sedimentary rocks. Slopes are 4 to 50 percent. Elevations are 5,300 to 6,800 feet. The climate is cool, semiarid with warm, dry summers and cool, moist winters. The mean annual precipitation is 10 to 14 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 Hopeka and Izar series. These soils have more than 35 percent rock fragments in their control section and are shallow to hard bedrock.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderately slow permeability.
USE AND VEGETATION: Rangeland and wildlife habitat. The present vegetation is mainly black sagebrush, little rabbitbrush, bluebunch wheatgrass and Indian ricegrass.
DISTRIBUTION AND EXTENT: Northeast Nevada. These soils are not extensive. MLRA 25, 28B.
MLRA OFFICE RESPONSIBLE: Reno, Nevada
SERIES ESTABLISHED: Elko County, Nevada, northeast part, 1986.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 3 inches; (A1 and A2 horizons)
Paralithic contact - The boundary at about 7 inches (Cr horizon)
Particle-size control section - The zone from the surface of the soil to about 7 inches (A1, A2 and Bk horizons).
The superactive cation exchange activity class was added in 03/2003 to the taxonomic classification by the National Soil Survey Center on request of the Reno MLRA office, without review of the soil series property data. The remainder of this document has not been updated.