LOCATION LONEGRAVE OR
Established Series
Rev. JVC-JBF
11/2022
LONEGRAVE SERIES
The Lonegrave series consists of moderately deep, well drained soils that formed in colluvium derived from volcanic rocks. Lonegrave soils are on plateaus, hills, canyonlands, and mountains. Slopes are 5 to 70 percent. The mean annual precipitation is about 280 mm and the mean annual temperature is about 7 degrees C.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Xeric Haplocambids
TYPICAL PEDON: Lonegrave very stony clay loam--on a 45 percent west-facing slope--rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 25 cm; light brownish gray (10YR 6/2) very stony clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium granular structure; slightly hard, friable, moderately sticky and slightly plastic; many very fine and fine roots; many very fine tubular and irregular pores; 15 percent stones, 10 percent cobbles, and 25 percent gravel; neutral (pH 6.8); gradual wavy boundary. (8 to 38 cm thick)
Bw--25 to 56 cm; yellowish brown (10YR 5/4) very gravelly clay loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, firm, moderately sticky and slightly plastic; common very fine and fine roots; many very fine irregular pores; 2 percent stones, 15 percent cobbles, and 30 percent gravel; neutral (pH 7.2); abrupt wavy boundary. (25 to 64 cm thick)
R--56 cm; igneous (volcanic) rock.
TYPE LOCATION: Harney County, Oregon; in the Trout Creek Mountains west of Center Ridge and about 0.5 mile east of the junction of Big Trout Creek and Cove Canyon; in the SE 1/4 of the NE 1/4 of section 36, T. 39 S., R. 37 E.; USGS Pole Canyon 7.5 minute topographic quadrangle; latitude 42 degrees 8 minutes 38 seconds N and longitude 118 degrees 18 minutes 53 seconds W; NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, moist in winter and early spring; aridic soil moisture regime that borders on xeric.
Mean annual soil temperature: 8 to 10 degrees C.
Depth to base of cambic horizon: 36 to 100 cm.
Depth to bedrock: 50 to 100 cm to a lithic contact.
Particle-size control section - Clay content: 20 to 35 percent.
Rock fragments: 35 to 70 percent, mainly cobbles and gravel. Lithology of fragments are volcanic rocks such as basalt or welded tuff.
A horizon
Value: 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Reaction: Neutral or slightly alkaline
Bw horizon
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 3 or 4 dry, 2 through 4 moist.
Texture: Very cobbly clay loam, very cobbly loam, or very gravelly clay loam.
Rock fragments: 0 to 5 percent stones, 10 to 30 percent cobbles, and 15 to 40 percent gravel.
Reaction: Neutral or slightly alkaline
Bk horizon (when present)
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 3 or 4 dry, 2 through 4 moist
Texture: Extremely stony sandy loam, very stony sandy loam, extremely cobbly sandy loam, or very cobbly loam
Rock fragments: 15 to 45 percent gravel, 5 to 15 percent cobbles, and 5 to 25 percent stones
Reaction: Slightly alkaline or moderately alkaline
Calcium carbonate equivalent: 0 to 1 percent
Salinity (EC): 0 to 2 mmhos/cm
Sodicity (SAR): 0 to 2
Other features: Some pedons have a thin BC horizon.
COMPETING SERIES: These are the
Cewat,
Darkcanyon,
Drinkwater,
Finley,
Kiona,
Minat,
Nibbs,
Veet,
Veta, and
Wifton series.
Cewat soils have mean annual soil temperature of 12 to 15 degrees C.
Darkcanyon soils are dominated by rock fragments which are channers and/or flagstones of schist.
Drinkwater,
Finley,
Kiona,
Minat,
Nibbs,
Veet,
Veta, and
Wifton soils are very deep.
GEOGRAPHIC SETTING: Lonegrave soils are on plateaus, hills, canyonlands and mountains. They typically occur on shoulder, backslope, and footslope positions. These soils formed in colluvium derived from volcanic rock such as welded tuff or basalt. Slopes are 5 to 70 percent. Elevations range from 1,250 to 2,170 meters. The climate is semiarid and characterized by cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 360 mm, the mean annual temperature is 7 to 9 degrees C, and the frost-free period is 50 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Cleavage,
Ninemile, and
Westbutte soils. Cleavage and Ninemile soils are shallow to lithic contacts, and have mollic epipedons and argillic horizons. Westbutte soils are on adjacent north-facing slopes and have argillic horizons.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; high surface runoff; moderately low saturated hydraulic conductivity.
USE AND VEGETATION: Lonegrave soils are used for livestock grazing. The vegetation commonly is bluebunch wheatgrass, Thurber's needlegrass, and Wyoming big sagebrush.
DISTRIBUTION AND EXTENT: Southeastern Oregon. These soils are extensive with about 140,000 acres of the series mapped to date. MLRA 23.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Lake County (Southern Part), Oregon, 1991.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 25 cm (A horizon).
Cambic horizon - The zone from 25 to 56 cm (Bw horizon).
Lithic contact - The boundary at 56 cm to underlying hard, unweathered bedrock (R layer).
Particle-size control section - The zone from 25 to 56 cm (Bw horizon).
ADDITIONAL DATA: Previous authors and editors include: CFL-TDT-TM.
National Cooperative Soil Survey
U.S.A.