LOCATION ATLOW NV+OREstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Lithic Xeric Haplargids
TYPICAL PEDON: Atlow very gravelly loam--rangeland. (Colors are for dry soil unless otherwise noted.) The surface is covered with 10 percent cobbles and 40 percent gravel.
A--0 to 8 cm; pale brown (10YR 6/3) very gravelly loam, brown (10YR 4/3), moist; moderate thin platy structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine roots; many very fine vesicular pores; 10 percent cobbles and 25 percent gravel; moderately alkaline (pH 8.0); abrupt smooth boundary. (3 to 23 cm thick)
Bt--8 to 18 cm; pale brown (10YR 6/3) very gravelly clay loam, dark yellowish brown (10YR 4/4), moist; moderate fine subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; common fine roots and common very fine roots; common very fine interstitial pores; common distinct clay films on faces of peds and lining pores; 10 percent cobbles and 25 percent gravel; moderately alkaline (pH 8.0); clear smooth boundary. (0 to 15 cm thick)
Btk--18 to 36 cm; yellowish brown (10YR 5/4) very gravelly clay loam, dark yellowish brown (10YR 4/4), moist; moderate angular blocky structure; hard, friable, very sticky and very plastic; common fine roots and common very fine roots; common very fine interstitial and few very fine tubular pores; common distinct clay films on faces of peds and lining pores; 2 percent fine platy weakly cemented carbonate concretions on bottom of rock fragments; 15 percent cobbles and 30 percent gravel; moderately alkaline (pH 8.0); abrupt irregular boundary. (16 to 36 cm thick)
R--36 cm; chert bedrock, fractured at intervals of 45 to less than 100 cm; fine platy weakly cemented carbonate concretions in cracks.
TYPE LOCATION: Lander County, Nevada; about 30 miles south of Battle Mountain approximately 1,200 feet east and 1,050 feet north of the southwest corner of section 31, T 29 N, R 43 E; latitude 40 degrees 24 minutes 15 seconds N and longitude 117 degrees 11 minutes 17 seconds W; NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist from mid-fall through spring, dry from summer through early fall; Aridic moisture regime that borders on xeric.
Mean annual soil temperature: 9 to 11 degrees C.
Depth to base of argillic horizon: 36 to 50 cm.
Depth to bedrock: 36 to 50 cm to a lithic contact.
Other features: There is not an abrupt textural change between the A horizon and an argillic horizon.
Particle-size control section - Clay content: 27 to 35 percent.
Rock fragments: 35 to 50 percent, dominantly gravel and cobbles.
A horizon
Value: 6 or 7 dry, 3 through 5 moist.
Chroma: 2 or 3, dry or moist.
Reaction: Slightly alkaline or moderately alkaline.
Bt horizon (when present)
Value: 5 through 7 dry, 4 or 5 moist.
Chroma: 2 through 4, dry or moist.
Texture: Clay loam or sandy clay loam.
Texture modifiers: Very gravely or very cobbly.
Structure: Weak or moderate angular blocky or subangular blocky.
Reaction: Moderately alkaline or strongly alkaline.
Btk horizon
Value: 5 through 7 dry, 4 or 5 moist.
Chroma: 2 through 4, dry or moist.
Texture: Clay loam or sandy clay loam.
Texture modifiers: Very gravely or very cobbly.
Structure: Weak or moderate angular blocky or subangular blocky.
Reaction: Moderately alkaline or strongly alkaline.
Secondary carbonates: The matrix is noneffervescent; carbonate coats are on the bottoms of rock fragments.
Consistence: Slightly hard or hard, moderately sticky or very sticky, moderately plastic or very plastic.
COMPETING SERIES: These are the Boomstick, Checkett, Chubard, Cottle, Doorkiss, Fortyday, Gabbvally, Hooplite, Nevo, Olac, Old Camp, Phliss, Richinde, Rowel, Soughe, Stewval, and Thike series.
Boomstick soils contain 50 to 75 percent mainly channers with some flagstone. Checkett soils are calcareous in all parts and have hues redder than 5YR. Cottle soils are neutral or slightly alkaline in the argillic horizon. Dorkiss has an abrupt textural change between the A horizon and the Bt horizon and average 50 to 70 percent gravel in the particle-size control section. Fortyday and Gabbvally soils contain less than 25 percent clay in the particle-size control section. Thike soils have less than 18 percent clay in the control section. Chubard and Hooplite soils are less than 36 cm deep. Nevo soils are neutral or slightly alkaline and are 13 to 25 cm to a lithic contact. Olac soils have 60 to 75 percent rock fragments in the Bt horizon and average 18 to 27 percent clay in the control section. Old Camp soils have Bt horizons with 50 to 75 percent rock fragments, mainly cobbles and stones. Phliss soils have Btk horizons and have channery rock fragments. Richinde soils are intermittently moist for 10 to 20 days cumulative from July through September due to convection storms. Rowel soils are less than 36 cm deep and have Bt horizons with more than 35 percent clay. Soughe soils lack carbonates in the profile, have rock fragments that are mainly cobbles and stones and lack lime coatings on rock fragments in the argillic horizon. Stewval soils are less than 36 cm deep, and are calcareous in all parts.
GEOGRAPHIC SETTING: Atlow soils are on hills and mountains. They typically occur on summit, shoulder, and backslope positions. These soils formed in residuum weathered from chert, argillite, shale, altered rhyolitic tuff, and andesite. Slopes are 2 to 75 percent. Elevations range from 1,280 to 2,440 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 250 mm (in central Oregon ranging as low as 150 mm), the mean annual temperature is 7 to 9 degrees C., and the frost-free period is 100 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Burrita and Favret soils. Burrita soils are clayey-skeletal. Favret soils are moderately deep and have less than 35 percent rock fragments.
DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability; moderately high saturated hydraulic conductivity.
USE AND VEGETATION: Atlow soils are used for livestock grazing and wildlife habitat. The present vegetation is black sagebrush, bottlebrush squirreltail, Indian ricegrass, and Thurber's needlegrass.
DISTRIBUTION AND EXTENT: North-central Nevada and south-central Oregon. These soils are moderately extensive. MLRAs 24, 27 and 28B.
MLRA OFFICE RESPONSIBLE: Reno, Nevada.
SERIES ESTABLISHED: Lander County, Nevada, North Part, 1985.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 15 cm (A horizon).
Argillic horizon - The zone from 8 to 38 cm (Bt and Btk horizons).
Identifiable secondary carbonates - The zone from 18 to 36 cm (Btk horizon).
Lithic contact - The boundary at 36 cm to underlying unweathered bedrock (R layer).
Particle-size control section - The zone from 8 to 36 cm (Btk horizon).
ADDITIONAL DATA: The pedon type location was moved 6/2009 to separate Lahontan sagebrush and black sagebrush.
NASIS Pedon and Site ID 07NV768001.