LOCATION HENNINGSEN              NV

Established Series
Rev. ELS-EWB-JVC-JBF
03/2017

HENNINGSEN SERIES

The Henningsen series consists of very deep, moderately well drained soils that formed in alluvium derived from mixed rocks. Henningsen soils are on flood plains. Slopes are 0 to 2 percent. The mean annual precipitation is about 230 mm and the mean annual temperature is about 9 degrees C.

TAXONOMIC CLASS: Coarse-loamy over sandy or sandy-skeletal, mixed, superactive, mesic Oxyaquic Haploxerolls

TYPICAL PEDON: Henningsen gravelly loam--irrigated pasture (Colors are for dry soil unless otherwise noted.)

Ap--0 to 18 cm; grayish brown (10YR 5/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine, few medium roots; many fine and medium interstitial pores; 25 percent gravel; few mica grains; neutral (pH 6.8); clear smooth boundary. (8 to 20 cm thick)

A--18 to 33 cm; grayish brown (10YR 5/2) gravelly very fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine and fine interstitial and common medium tubular pores; few fine and medium faint brown (10YR 4/3) moist, masses of iron accumulation; 30 percent gravel; neutral (pH 7.0); clear smooth boundary. (8 to 18 cm thick)

2C1--33 to 51 cm; grayish brown (2.5Y 5/2) very gravelly loamy coarse sand, dark grayish brown (2.5Y 4/2) moist; single grain; loose, nonsticky and nonplastic; common very fine and fine roots; many very fine and fine interstitial pores; common fine distinct dark yellowish brown (10YR 4/4) moist, coats of iron accumulation on bottoms of rock fragments; 40 percent gravel and 15 percent cobbles; neutral (pH 6.8); clear smooth boundary. (8 to 20 cm thick)

2C2--51 to 152 cm; grayish brown (2.5Y 5/2) extremely gravelly coarse sand, dark grayish brown (2.5Y 4/2) moist; single grain; loose, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; common fine distinct dark yellowish brown (10YR 4/4) moist, coats of iron accumulation on bottoms of rock fragments; 50 percent gravel and 20 percent cobbles; neutral (pH 6.6).

TYPE LOCATION: Douglas County, Nevada; in Carson Valley about 2 miles south of Gardnerville adjacent to Rocky Slough; 2,500 feet north and 1,400 feet east of the southwest corner of section 9, T. 12 N., R. 20 E.; USGS Gardnerville 7.5 minute topographic quadrangle; latitude 38 degrees 55 minutes 03 seconds N and longitude 119 degrees 44 minutes 47 seconds W; WGS84 Decimal Degrees 38.9173889 latitude, -119.7462778 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry in the moisture control section; moist in winter and spring; dry in summer and fall unless irrigated; aridic soil moisture regime that borders on xeric.
Mean annual soil temperature: 9 to 12 degrees C.
Mollic epipedon thickness: 18 to 36 cm.
Depth to strongly contrasting sandy-skeletal material: 28 to 50 cm.
Depth to horizons with aquic conditions: 76 to 100 cm.

Particle-size control section - Clay content: 8 to 18 percent in the upper part of the profile and 1 to 8 percent in the contrasting lower part.
Rock fragments: 5 to 30 percent in the upper part of the profile and 50 to 80 percent in the contrasting lower part, mainly gravel. Lithology of fragments is mixed.

Ap horizon
Hue: 10YR or 2.5Y.
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 1 or 2 percent.
Redoximorphic features: Redox concentrations occur as masses of iron accumulation in some horizons.

A horizons
Hue: 10YR or 2.5Y.
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Texture: Loam, gravelly loam, or gravelly very fine sandy loam.
Organic matter content: 1 or 2 percent.
Redoximorphic features: Redox concentrations occur as masses of iron accumulation in some horizons.

2C horizons
Hue: 10YR or 2.5Y.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 1 or 2, dry or moist.
Texture: Very gravelly loamy coarse sand, very gravelly coarse sand, or extremely gravelly coarse sand.
Rock fragments: 50 to 80 percent.
Redoximorphic features: Redox concentrations occur as masses of iron accumulation within the horizon matrix or as coats of iron accumulation on rock fragments.

COMPETING SERIES: This is the Morwen series. Morwen soils have strongly contrasting sandy-skeletal material at depths of 50 to 100 cm from the soil surface.

GEOGRAPHIC SETTING: Henningsen soils are on flood plains. They formed in alluvium derived from mixed rocks but with a strong influence from granitic rocks. Slopes are 0 to 2 percent. Elevations range from 1,400 to 1,450 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 250 mm, mean annual temperature is 8 to 11 degrees C, and the frost-free period is 90 to 110 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Job, Kazul, and Whitmire soils and the competing Morwen soil. Job soils are fine-loamy, have ochric epipedons, and have horizons with identifiable secondary carbonates. Kazul soils are fine-loamy, have cambic horizons, and have strongly contrasting sandy-skeletal material at depths of 100 to 127 cm from the soil surface. Whitmire soils are fine-loamy over sandy or sandy-skeletal, have thick mollic epipedons, and have aquic conditions within 76 cm of the soil surface.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained; low surface runoff; moderately high saturated hydraulic conductivity. Endosaturation is present with an apparent seasonal high water table between 76 and 100 cm (moderately deep free water occurrence class) from December through May. Cumulative annual duration classes are Common or Persistent. These soils are susceptible to occasional flooding for brief periods between December and May.

USE AND VEGETATION: Henningsen soils are used for irrigated pasture, hayland, rangeland, and urban development. Irrigated crops are alfalfa and legume-grasses mixtures. Vegetation in rangeland is willows, cottonwood, sedges, and Juncus sp. These soils are also a source of gravel (aggregate) for concrete manufacture.

DISTRIBUTION AND EXTENT: Western Nevada. These soils are not extensive. MLRA 26.

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

SERIES ESTABLISHED: Garfield County Area, Washington, 1970.

REMARKS: The revision of 5/2000 changed the particle-size class from sandy-skeletal to coarse-loamy over sandy or sandy-skeletal and updated the taxonomic subgroup from Aquic Haploxerolls to Oxyaquic Haploxerolls. The Henningsen soil mapped in Garfield County, Washington needs correlation to another series.

Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 33 cm (Ap and A horizons).
Major lithologic discontinuity - The abrupt change to sandy-skeletal material with the boundary at 33 cm (between the A and 2C1 horizons).
Aquic conditions - The conditions of endosaturation, reduction, and redoximorphic features between 76 and 152 cm at certain times during normal years (parts of the 2C2 horizon).
Particle size control section - The zone from 25 to 100 cm (2C1 horizon and parts of the A and 2C2 horizons).

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National Cooperative Soil Survey
U.S.A.