LOCATION JUMPCREEK               ID

Established Series
Rev. ALH/CLM
01/2019

JUMPCREEK SERIES

The Jumpcreek series consists of moderately deep, well drained soils with moderately slow permeability that formed in slope alluvium and residuum from rhyolite. Jumpcreek soils are on structural benches. Slopes range from 3 to 30 percent. Average annual precipitation is 300 mm and average annual temperature is 9 degrees C.

TAXONOMIC CLASS: Clayey-skeletal, smectitic, mesic Argiduridic Argixerolls

TYPICAL PEDON: Jumpcreek gravelly loam -- on a northwest-facing slightly convex slope of 15 percent, in seeded rangeland, at 1,435 meter elevation. (Colors are for air-dry soils unless otherwise stated. When described on October 6, l983, the soil was dry throughout.)

A--0 to 15 cm; grayish brown (10YR 5/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium subangular blocky structure parting to moderate fine and medium granular; soft, very friable, slightly sticky and slightly plastic; common very fine, fine, and medium roots; many very fine and fine, few medium vesicular pores; 20 percent gravel; slightly alkaline (pH 7.4); clear smooth boundary. (13 to 20 cm thick)

BA--15 to 30 cm; brown (10YR 5/3) very gravelly loam, dark brown (10YR 3/3) moist; moderate fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common very fine and fine, few medium roots; common fine tubular pores; common faint clay films on faces of peds; 35 percent gravel; neutral (pH 7.l); clear smooth boundary. (0 to 23 cm thick)

Bt--30 to 53 cm; yellowish brown (10YR 5/4) very gravelly clay loam, brown (10YR 4/3) moist; moderate fine angular blocky structure; very hard, firm, very sticky and very plastic; few very fine and fine roots; common fine tubular pores; many distinct clay films on faces of peds and in pores; 50 percent gravel; neutral (pH 7.0); clear wavy boundary. (10 to 23 cm thick)

Btq--53 to 76 cm; brown (7.5YR 5/4) extremely gravelly clay, brown (7.5YR 4/4) moist; strong fine angular blocky structure; very hard, very firm, very sticky and very plastic; few fine roots; few fine tubular pores; many prominent clay films on faces of peds and in pores; 65 percent gravel (with thin silica coatings on undersides); slightly alkaline (pH 7.4); clear wavy boundary. (0 to 30 cm thick)

Bkq--76 to 91 cm; very pale brown (10YR 7/3) weakly cemented extremely gravelly sandy loam, yellowish brown (10YR 5/4) moist, with discontinuous distinct siliceous laminar cap 1 mm thick; massive; very hard, firm, nonsticky and nonplastic; 75 percent gravel, 10 percent cobbles; strong effervescence; strongly alkaline (pH 8.8); gradual wavy boundary. (13 to 25 cm thick)

R--91 cm; fractured rhyolite.

TYPE LOCATION: Owyhee County, Idaho; about 5 miles west and 10 miles south of Marsing; about 1,000 feet west and 2,000 feet south of the northeast corner of section 27, T. 1 N., R. 5 W.; USGS Jump Creek Canyon 7.5 minute topographic quadrangle; latitude 43 degrees 23 minutes 45 seconds N and longitude 116 degrees 54 minutes 49 seconds W; WGS84 Decimal Degrees 43.3958333 latitude, -116.9136111 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, moist in winter and spring and dry late June through mid-October; aridic soil moisture regime bordering on xeric.
Mollic epipedon thickness: 20 to 36 cm.
Depth to base of argillic: 40 to 76 cm.
Depth to bedrock: 56 to 100 cm
Mean annual soil temperature: 9 to 11 degrees C.

Particle-size control section - Clay content: 35 to 45 percent.
Rock fragments: 35 to 70 percent, mainly gravel.

A horizon
Value: 2 or 3 moist.
Chroma: 2 or 3 dry or moist.
Rock fragments: 20 to 35 percent.
Reaction (pH): Neutral or slightly alkaline.

Bt horizon
Hue: 7.5YR or 10YR
Chroma: 3 or 4 dry or moist
Texture: Clay loam or clay.
Texture modifiers: Very gravelly or extremely gravelly.
Reaction (pH): Neutral or slightly alkaline.

Bkq horizon
Value: 5 or 6 moist.
Chroma: 3 or 4 dry or moist.
Texture: Loam or sandy loam.
Rock fragments: 50 to 90 percent.
Calcium carbonate equivalent: 2 to 15 percent.
Reaction (pH): Moderately alkaline or strongly alkaline.

COMPETING SERIES: There are no other soils listed in the same family.

GEOGRAPHIC SETTING: Jumpcreek soils are undulating to hilly on sideslopes and summits of dissected structural benches at elevations of 1,295 to 1,433 meters. Slopes range from 3 to 30 percent. These soils formed in slope alluvium and residuum from rhyolite. The climate is cool and moist in winter and hot and dry in summer. Average annual precipitation ranges from 280 to 330 mm, and average annual temperature ranges from 8 to 9 degrees C. The frost-free period is 95 to 115 days.

GEOGRAPHICALLY ASSOCIATED SOILS: This is the Frenchjohn series. Frenchjohn soils have an abrupt textural change and lack a cemented horizon. They are on more moist northeast aspects.

DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderately slow permeability.

USE AND VEGETATION: Jumpcreek soils are used mainly for rangeland and wildlife habitat. The dominant natural vegetation is basin big sagebrush, bluebunch wheatgrass, Sandberg bluegrass, and arrowleaf balsamroot.

DISTRIBUTION AND EXTENT: Southwestern Idaho. Jumpcreek soils are of small extent. MLRA25.

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

SERIES ESTABLISHED: Owyhee County Area, Idaho, l992.

REMARKS: Diagnostic horizons and other features recognized in this pedon:
Mollic epipedon - The zone from soil surface to 30 cm (A and BA horizons).
Argillic horizon - The zone from 30 to 76 cm (Bt and Btq horizons).
Duric feature- The zone from 76 to 91 cm (Bkq horizon).
Lithic contact - The boundary at 91 cm (R layer).
Particle-size control section - The zone from 30 to 76 cm (Bt and Btq).

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National Cooperative Soil Survey
U.S.A.