LOCATION YONNA              OR
Established Series
Rev. JSC/AON/RWL/SMM
06/2009

YONNA SERIES


The Yonna series consists of very deep, somewhat poorly drained soils that formed in mixed alluvium with layers of volcanic ash and pumice. Yonna soils are on flood plains and stream terraces and have slopes of 0 to 2 percent. The mean annual precipitation is about 16 inches and the mean annual temperature is about 44 degrees F.

TAXONOMIC CLASS: Loamy over ashy or ashy-pumiceous, aniso, mixed over glassy, superactive Aquandic Haplocryepts

TYPICAL PEDON: Yonna silt loam, pastureland. (Colors are for moist soil unless otherwise noted.)

Az--0 to 0.5 inches; very dark gray (2.5Y 3/1) silt loam; gray (2.5Y 6/1) dry; massive; very hard, very firm, slightly sticky, slightly plastic; electrical conductivity of 19 mmhos/cm; violently effervescent; strongly alkaline (pH 9.0); abrupt broken boundary. (0 to 5 inches thick)

AB--0.5 to 7 inches; black (2.5Y 2.5/1) clay loam; gray (2.5Y 5/1) dry; strong very coarse subangular blocky structure parting to moderate thick platy; very hard, very firm, slightly sticky, moderately plastic; common very fine and fine roots; few very fine and fine tubular pores; 5 percent weakly cemented pumice fine and medium paragravel; electrical conductivity of 1.6 mmhos/cm; very slightly effervescent; moderately alkaline (pH 8.0); abrupt wavy boundary. (3 to 20 inches thick)

Bw1--7 to 16 inches; black (2.5Y 2.5/1) loam; gray (10YR 6/1) dry; weak coarse and medium subangular blocky structure; moderately hard, friable, slightly sticky, moderately plastic; common very fine and fine roots; few fine tubular, and common very fine and fine irregular pores; 8 percent weakly cemented pumice fine paragravel; electrical conductivity of 0.7 mmhos/cm; slightly alkaline (pH 7.6); gradual wavy boundary. (5 to 20 inches thick)

2Bw2--16 to 26 inches; very dark gray (2.5Y 3/1) paragravelly ashy coarse sandy loam; gray (10YR 6/1) dry; massive; soft, friable, nonsticky, nonplastic; common very fine and fine roots; many fine and few medium irregular pores; 18 percent weakly cemented pumice fine and medium paragravel; neutral (pH 7.0); abrupt wavy boundary. (7 to 14 inches thick)

3Ab--26 to 42 inches; black (10YR 2/1) loam; gray (10YR 6/1) dry; moderate medium subangular blocky structure; moderately hard, friable, slightly sticky, moderately plastic; common very fine and fine roots; few coarse and common fine and medium irregular pores; 5 percent (common) fine faint weakly cemented iron-manganese nodules; slightly alkaline (pH 7.4); clear wavy boundary. (0 to 25 inches thick)

3Bwb--42 to 54 inches; very dark grayish brown (10YR 3/2) clay loam; gray (10YR 5/1) dry; strong coarse subangular blocky structure; very hard, firm, moderately sticky, moderately plastic; few fine and very fine roots; few medium and common fine irregular and common fine tubular pores; 15 percent (few) discontinuous prominent very dark grayish brown (10YR 3/2) pressure faces on all faces of peds and 10 percent (few) discontinuous prominent very dark grayish brown (10YR 3/2) silt coats on all faces of peds; 25 percent (many) medium faint weakly cemented iron-manganese nodules in matrix and 2 percent (common) medium distinct iron depletions in matrix; 5 percent indurated fine gravel; neutral (pH 7.2); clear wavy boundary. (0 to 25 inches thick)

4BC--54 to 63 inches; very dark grayish brown (2.5Y 3/2) very gravelly coarse sand; light olive brown (2.5Y 5/3) dry; single grain; loose, nonsticky, nonplastic; many fine interstitial pores; 5 percent weakly cemented pumice fine paragravel and 50 percent indurated fine and medium gravel; neutral (pH 6.9).

TYPE LOCATION: Klamath County, Oregon; about 1.6 miles north and 0.5 miles east of the town of Beatty; 1,940 feet south and 2,440 feet east of the northwest corner of Section 11, T. 36 S, R. 12 E, Beatty, Oregon USGS quadrangle; 642907.77E, 4702878.48N, Datum NAD83, Zone 10; lat. 4227'54.25711" north, and long. 12115'42.25406" west.

RANGE IN CHARACTERISTICS:

Soil Moisture - Moisture control section (4 to 12 inches) dry throughout for 60 to 90 consecutive days during the four month period following the summer solstice; (xeric moisture regime). The soils are saturated throughout during the month of March.

Soil Temperature - cryic regime
Mean annual soil temperature - 44 to 47 degrees F.
Mean summer soil temperature - 56 to 59 degrees F.
Mean winter soil temperature - 37 to 43 degrees F.

Particle-size control section: from 10 to 40 inches below the mineral soil surface. Depth to the ashy middle part is 14 to 30 inches and depth to the loamy lower part is 20 to 40 inches
Upper, loamy part - 15 to 30 percent clay
Middle, ashy part - 2 to 30 percent clay and is 7 to 14 inches thick
Lower, loamy part - 15 to 35 percent clay

Diagnostic horizons and features:
Depth to ashy-modified soil textures having aquandic subgroup properties - 14 to 30 inches. The horizons and layers having ashy textural modifiers have 30 to 60 percent glass and the ammonium oxalate (Al+1/2Fe) is 0.2 to 0.5.
Depth to the 3Ab - 20 to 40 inches
Depth to 4BC - 50 to over 60 inches

Az horizon (where present):
Value: 3 or 4 moist, 6 or 7 dry
Chroma: 1 or 2, moist or dry
Texture: silt loam or loam
Pararock fragment content: 0 to 10 percent fine pumice paragravel
EC: 4 to 8 mmhos/cm
SAR: 5 to 10
pH: 8.0 to 9.0

AB or A horizons:
Hue: 10YR or 2.5Y
Value: 3 or 4 moist, 4 or 5 dry
Chroma: 1 or 2, moist or dry
Texture: clay loam, loam or sandy loam
Pararock fragment content: 0 to 10 percent fine pumice paragravel
EC: 2 to 4 mmhos/cm
SAR: 0 to 5
pH: 7.5 to 9.0

Bw horizon:
Hue: 10YR or 2.5Y
Value: 2.5 to 5 moist, 6 to 8 dry
Chroma: 1 through 3, moist or dry
Texture: loam or sandy loam
Pararock fragment content: 0 to 10 percent fine pumice paragravel
EC: 0 to 1 mmhos/cm

2Bw horizon:
Hue: 10YR or 2.5Y
Value: 3 or 4 moist, 6 or 7 dry
Chroma: 1 through 3, moist or dry
Texture: ashy sandy clay loam, ashy coarse sandy loam, or ashy loamy coarse sand, with or without a paragravelly modifier
Pararock fragment content: 2 to 30 percent fine pumice paragravel
EC: 0 to 2 mmhos/cm
SAR: 0 to 5
pH: 7.0 to 8.5

3Ab and 3Bwb horizons:
Hue: 10YR or 2.5Y
Value: 2 to 4 moist, 4 to 8 dry
Chroma: 1 to 3, moist or dry
Texture: loam, silt loam, clay loam, sandy clay loam or silty clay loam
Pararock fragment content: 2 to 10 percent fine pumice paragravel
Rock fragment content: 2 to 10 percent fine gravel
EC: 0 to 2 mmhos/cm
SAR: 0 to 2
pH: 6.8 to 8.0

4BC horizon (where present):
Hue: 10YR or 2.5Y
Value: 2 through 4 moist, 3 through 5 dry
Chroma: 2 or 3, moist or dry
Texture: very gravelly coarse sand, gravelly sandy loam, gravelly loam
Pararock fragment content: 2 to 10 percent fine pumice paragravel
Rock fragment content: 15 to 60 percent fine and medium gravel
EC: 0 to 2 mmhos/cm
SAR: 0 to 2
pH: 6.8 to 8.0

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: Yonna soils are on narrow aggrading flood plains and low terraces. Elevations range from 4,200 to 4,400 feet. The soils formed in alluvium derived from mixed sediments weathered mainly from diatomite, tuff and basalt, over alluvium derived from ash and mixed sediments, over alluvium derived from mixed sediments. The climate is characterized by cold moist winters and cool dry summers. The mean annual precipitation is 14 to 20 inches. The mean January temperature is 27 to 30 degrees F; the mean July temperature is 60 to 63 degrees F; and the mean annual temperature is 42 to 48 degrees F. The frost-free period is 40 to 70 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dilman, Klamath, and Ontko soils. Dilman, Klamath and Ontko soils are on a lower flood plain position than Yonna soils, are poorly or very poorly drained and have a mollic epipedon. Dilman soils have depths to the lower, loamy material of greater than 40 inches. Klamath soils are fine-silty. Ontko soils are fine-loamy.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained; moderately slow permeability. The soil is saturated throughout in March. A seasonal high water table is at a depth of 0 to 40 inches from February to June, at a depth of 40 to 120 inches in July and August and November to January, and over 120 inches in September and October. This soil is subject to occasional periods of brief flooding from March to May.

USE AND VEGETATION: The soils are used for irrigated pasture, livestock grazing, and wildlife habitat. Vegetation on noncultivated areas is mainly silver sagebrush, green rabbitbrush, inland saltgrass, basin wildrye, and Nevada bluegrass. In areas with altered hydrology, the saline conditions and salt-tolerant vegetation is lacking.

DISTRIBUTION AND EXTENT: Stream valleys near the southern fringe of the pumice-mantled region in south-central Oregon; MLRA 21. The soils are inextensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Klamath County, Oregon, 1977.

REMARKS: Diagnostic horizons and features recognized in this pedon:

Ochric epipedon

Cambic horizon - from 7 to 54 inches

Aquandic soil properties - from 16 to 26 inches (2Bw2 horizon)

Redoximorphic features - iron-manganese nodules from 26 to 42 inches (3Ab horizon)and iron-manganese nodules and iron depletions from 42 to 54 inches (3Bwb horizon)

Particle-size control section - from 10 to 40 inches, with 10 to 16 inches meeting loamy family criteria, 16 to 26 inches meeting ashy family criteria, and 26 to 40 inches meeting loamy family criteria (aniso).


National Cooperative Soil Survey
U.S.A.