LOCATION YOUTLKUE OR

Established Series
Rev. GJW-TDT-JVC-JBF
06/2011

YOUTLKUE SERIES

The Youtlkue series consists of moderately deep, somewhat poorly drained soils that formed in lacustrine deposits derived from volcanic ash. Youtlkue soils are on depressions on lakebeds. Slopes are 0 to 2 percent. The mean annual precipitation is about 230 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Ashy, glassy, frigid Vitrixerandic Aquicambids

TYPICAL PEDON: Youtlkue ashy silt loam--on a nearly level depression dominated by creeping wildrye at an elevation of 1,310 meters--rangeland. (Colors are for dry soil unless otherwise noted. When described on October 13, 1994, the soil was dry throughout.)

A--0 to 13 cm; light brownish gray (10YR 6/2) ashy silt loam, dark brown (10YR 3/3) moist; weak thin platy structure parting to weak fine subangular blocky; soft, very friable, nonsticky and nonplastic; many very fine and fine, few medium roots; common very fine interstitial pores; moderately alkaline (pH 8.0); clear smooth boundary. (8 to 25 cm thick)

Bw1--13 to 33 cm; light gray (10YR 7/1) ashy silt loam, dark brown (10YR 3/3) moist; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky and nonplastic; few very fine roots; many very fine interstitial pores; 10 percent very pale brown (10YR 8/2) glass aggregate or diatomite sand grains (0.1 to 0.5 mm diameter); slightly effervescent with disseminated lime; moderately alkaline (pH 8.4); clear smooth boundary.

Bw2--33 to 56 cm; light gray (10YR 7/2) ashy silty clay loam, brown (10YR 5/3) moist; weak fine and medium subangular blocky structure; hard, friable, slightly sticky and nonplastic; many very fine and fine roots; many very fine interstitial pores; 10 percent very pale brown (10YR 8/2) glass aggregate or diatomite sand grains (0.1 to 0.5 mm diameter); strongly effervescent with disseminated lime; strongly alkaline (pH 8.6); abrupt smooth boundary. (Combined thickness of the Bw horizons is 33 to 66 cm)

2C--56 to 81 cm; very pale brown (10YR 8/2) very paragravelly ashy silt loam, light gray (10YR 7/2) moist; very fine and fine angular blocky rock structure with many fractures; hard, firm, slightly sticky and nonplastic; many very fine roots along fractures; common very fine and fine tubular pores; about 50 percent weakly cemented paragravel; strongly effervescent with disseminated lime; fine-earth is assumed to be high in diatoms and very high in volcanic glass; moderately alkaline (pH 8.4); abrupt smooth boundary. (8 to 25 cm thick)

2Cr--81 cm; very pale brown (10YR 8/2) unfractured, weakly cemented lacustrine deposits; assumed to be high in diatoms and volcanic glass.

TYPE LOCATION: Lake County, Oregon; in the southeastern part of Fort Rock Valley; approximately 1,750 feet north and 600 feet east of the southwest corner of section 27, T. 27 S., R. 16 E.; USGS Thorn Lake 7.5 minute topographic quadrangle; latitude 43 degrees 11 minutes 50 seconds N and longitude 120 degrees 49 minutes 03 seconds W; NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually wet in winter and early spring for about 3 months, dry the remainder of the year; aridic moisture regime that borders on xeric.
Mean annual soil temperature: 7 to 8 degrees C.
Depth to base of cambic horizon and upper boundary of horizons with pararock fragments: 33 to 66 cm.
Depth to root-limiting layer: 50 to 90 cm to a paralithic contact. The paralithic materials below the contact are weakly cemented silty lacustrine deposits that are assumed to be high in diatoms and volcanic glass.

Particle-size control section - Clay content: Averages 18 to 27 percent.
Fine sand or coarser content: 15 to 35 percent.
Volcanic glass content: 30 to 90 percent in coarse silt through very coarse sand fractions.

A horizon
Value: 5 or 6 dry, 2 or 3 moist
Chroma: 2 or 3, dry or moist.

Bw horizons
Value: 6 or 7 dry, 3 through 5 moist.
Chroma: 1 or 2 dry, 3 or 4 moist.
Texture: Ashy silt loam, ashy silty clay loam, or ashy loam.
Reaction: Moderately alkaline or strongly alkaline.
Effervescence: Slightly effervescent to violently effervescent.

2C horizon
Texture: Very paragravelly ashy silt loam or extremely paragravelly ashy silt loam.
Pararock fragments: 35 to 80 percent paragravel.
Reaction: Moderately alkaline or strongly alkaline.
Other features: Pararock fragments consist of weakly cemented silty lacustrine deposits that are fractured. The majority of these fragments are water-stable and will not slake after air-drying and soaking in water for at least one hour.

COMPETING SERIES: There are currently no other series in this family.

GEOGRAPHIC SETTING: Youtlkue soils are on depressions on lakebeds. These soils formed in lacustrine deposits derived mainly from volcanic ash. Slopes are 0 to 2 percent. Elevations range from 1,310 to 1,345 meters. The climate is semiarid and characterized by cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 250 mm, mean annual temperature is 6 to 7 degrees C, and the frost-free period is 50 to 80 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Abert, Horning, Morehouse, and Tonor soils. Abert and Tonor soils are ashy, very deep, have cambic horizons, and are on summit positions of lake terraces. Horning and Morehouse soils are ashy, very deep, have ashy sandy textures in the particle-size control section, and occur on stable dunes.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained; medium surface runoff; moderately high saturated hydraulic conductivity. Episaturation is present with perched free water between the soil surface and the paralithic contact (very shallow free water occurrence class) between February and April in most years. Cumulative annual duration class is Transitory. Some small areas of these soils are susceptible to rare ponding for brief duration in wet years from January through March with water a few cm deep. Most areas of these soils do not pond water in normal years.

USE AND VEGETATION: Youtlkue soils are used for livestock grazing and wildlife habitat. The native vegetation is mainly creeping wildrye.

DISTRIBUTION AND EXTENT: South-central Oregon. These soils are not extensive with about 1,800 acres of the series mapped to date. MLRA 23.

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

SERIES ESTABLISHED: Lake County (Northern Part), Oregon, 2006.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 18 cm (A horizon and part of the Bw1 horizon).
Cambic horizon - The zone from 13 to 56 cm (Bw1 and Bw2 horizons).
Vitrandic intergrade feature - The zone from the soil surface to 76 cm (A, Bw1, and Bw2 horizons and part of the 2C horizon).
Episaturation feature - The condition of perched ground water with an upper boundary between the soil surface and the underlying bedrock at certain times during normal years (parts of the A, Bw1, Bw2, and 2C horizons).
Paralithic contact - The boundary at 81 cm to underlying weakly cemented lacustrine deposits (2Cr layer).
Particle-size control section and ashy substitute class with glassy mineralogy - The zone from 25 to 89 cm (Bw2 and 2C horizons and part of the Bw1 horizon).

The revision of August 2004 updated the taxonomic class from Ashy, glassy, frigid Vitrixerandic Haplocambids and recognized the presence of episaturation. A prior revision in April 2001 updated the taxonomic class from Fine-silty, mixed, frigid Xeric Haplocambids.

ADDITIONAL DATA: The Bw2 horizon of the typical pedon at the series type location was reference sampled for the Soil Survey Laboratory (SSL), Lincoln, NE, as soil survey sample number S94OR-037-005 (pedon # 95P0061). Selected data for particle-size, chemical properties, and optical mineralogy are available for this horizon.

National Cooperative Soil Survey
U.S.A.