LOCATION OPHIR NVEstablished Series
TAXONOMIC CLASS: Sandy, mixed, mesic Aquic Haploxerolls
TYPICAL PEDON: Ophir gravelly sandy loam--hayland. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 10 inches; dark gray (10YR 4/1) gravelly sandy loam, black (10YR 2/1) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, and common fine roots; many fine interstitial pores; few fine distinct brown (7.5YR 4/3) moist masses of iron accumulation; 15 percent fine pebbles; neutral (pH 6.6); clear smooth boundary. (7 to 11 inches thick)
A--10 to 13 inches; dark gray (10YR 4/1) gravelly loamy coarse sand, black (10YR 2/1) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine and few fine roots; many very fine and fine interstitial pores; 15 percent fine pebbles; neutral (pH 6.6); gradual smooth boundary. (0 to 6 inches thick)
Cg1--13 to 30 inches; dark gray (10YR 4/1) gravelly sandy loam, black (10YR 2/1) moist; massive; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; many very fine interstitial pores; common medium distinct brown (10YR 4/3) moist masses of iron accumulation; 15 percent fine pebbles; neutral (pH 6.8); gradual smooth boundary. (7 to 19 inches thick)
Cg2--30 to 45 inches; grayish brown (10YR 5/2) gravelly loamy sand, very dark gray (10YR 3/1) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine interstitial pores; many coarse prominent brown (7.5YR 4/4) moist masses of iron accumulation; 15 percent fine pebbles; neutral (pH 6.8); gradual smooth boundary. (10 to 17 inches thick)
Cg3--45 to 60 inches; grayish brown (2.5Y 5/2) gravelly loamy sand, very dark grayish brown (2.5Y 3/2) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine interstitial pores; many coarse faint brown (10YR 4/3) moist masses of iron accumulation; 15 percent fine pebbles; neutral (pH 6.8).
TYPE LOCATION: Douglas County, Nevada; between the Carson Range and Carson Valley about 0.5 mile north-northwest of Sheridan; about 1,200 feet south and 400 feet east of the northwest corner of section 14, T. 12 N., R. 19 E.; USGS Minden 7.5 minute topographic quadrangle; 38 degrees 54 minutes 26 seconds north latitude and 119 degrees 49 minutes 24 seconds west longitude, NAD 27.
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 moisture regime that borders on xeric.
Mean annual soil temperature - 48 to 53 degrees F.
Mollic epipedon thickness - 10 to 20 inches.
Depth to horizons with aquic conditions - 20 to 30 inches.
Control section - Clay content: 3 to 10 percent; Rock fragments: 5 to 30 percent, mainly fine (2-5 mm) pebbles. Lithology of fragments are granitic rocks such as granite and granodiorite.
Other features - Some pedons contain toxic quantities of molybdenum.
Ap and A horizons - Hue: 10YR or neutral (N).
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 0 through 2, dry or moist.
Organic matter content: 1 to 3 percent.
Reaction: Moderately acid to neutral.
Redoximorphic features: Redox concentrations occur in most pedons as masses of iron accumulation; redox depletions may also occur as zones of iron depletion.
Cg horizons - Hue: 10YR through 5Y.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 1 or 2, dry or moist; chroma of 3 may be present with hue of 5Y.
Texture: Gravelly loamy sand, gravelly loamy coarse sand, gravelly coarse sand, loamy sand, gravelly sandy loam, or sandy loam.
Clay content: Averages 3 to 10 percent.
Rock fragments: 5 to 30 percent.
Reaction: Moderately acid to neutral.
Redoximorphic features: Redox concentrations occur as masses of iron accumulation; redox depletion of iron has occurred in the matrix and is indicated by strong gleying.
Other features: Mica grains are evident, but in amounts less than 65 percent by grain count.
COMPETING SERIES: At present, there are no other series in this family.
GEOGRAPHIC SETTING: Ophir soils are on alluvial fans. These soils formed in alluvium derived from granitic rocks. Slopes are 0 to 8 percent. Elevations range from 4,700 to 5,400 feet. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 8 to 12 inches, mean annual temperature is 46 to 51 degrees F., and the frost-free period is 90 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Godecke, Jubilee, and Mottsville soils. Godecke soils are fine-loamy, have natric horizons and horizons with durinodes, and have endosaturation at depths between 3.5 and 5 feet. Jubilee soils are coarse-loamy and have aquic conditions at depths within 20 inches of the soil surface. Mottsville soils are excessively drained and do not have redoximorphic features or endosaturation within the series control section.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; negligible to low surface runoff; rapid permeability. Endosaturation is present with an apparent seasonal high water table between 1.7 and 2.5 feet (moderately deep free water occurrence class) from December through May. Cumulative annual duration classes are Common or Persistent. These soils are susceptible to rare flooding for extremely brief periods throughout the year.
USE AND VEGETATION: Ophir soils are used for pasture and hay production. The present vegetation is mainly grass-legume hay or improved pasture supporting sedges, rushes, and grasses. Caution is needed when vegetation on this soil is used for pasture because it may contain molybdenum in levels which are toxic to domestic animals.
DISTRIBUTION AND EXTENT: Western Nevada. These soils are not extensive. MLRA 26.
MLRA OFFICE RESPONSIBLE: Reno, Nevada.
SERIES ESTABLISHED: Washoe County (South Part), Nevada, 1980.
REMARKS: This revision changes the taxonomic subgroup from Typic Endoaquolls to Aquic Haploxerolls.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 13 inches (Ap and A horizons).
Aquic conditions - The conditions of endosaturation, reduction, and redoximorphic features present from 20 to 60 inches at some time in normal years (Cg2 and Cg3 horizons and parts of the Cg1 horizon).
Particle size control section - The zone from 10 to 40 inches (A and Cg1 horizons and part of the Cg2 horizon).
ADDITIONAL DATA: Two pedons were sampled and characterized by the soil survey laboratory in Riverside, CA as sample numbers S58Nev-3-2 and S61Nev-3-2. Another pedon sampled as S61Nev-3-3 has properties that are not within the range of the series. The data for two of the three pedons is published in Soil Survey Investigations Report No. 23.