LOCATION JACKRABBIT MT
Established Series
EMR/RJS
04/2012
JACKRABBIT SERIES
The Jackrabbit series consists of very deep, excessively drained soils that formed in eolian sands deposits. These soils occur on dunes, dune fields, and interdunes. Slopes are 1 to 35 percent. Mean annual precipitation is about 390 millimeters. Mean annual air temperature is about 3 degrees C.
TAXONOMIC CLASS: Sandy, mixed Ustic Haplocryolls
TYPICAL PEDON: Jackrabbit loamy fine sand, in rangeland on a 6 percent slope at 2,049 meters elevation (colors are for dry soil unless otherwise noted).
A -- 0 to 31 centimeters; brown (10YR 4/3) loamy fine sand, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; common very fine roots; many very fine and fine irregular pores; neutral (pH 6.8); gradual smooth boundary. (25 to 50 cm thick)
Bw -- 31 to 85 centimeters; brown (10YR 5/3) loamy fine sand, dark grayish brown (10YR 4/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine roots; many very fine and fine irregular pores; neutral (pH 7.0); gradual smooth boundary. (13 to 99 cm thick)
C -- 85 to 159 centimeters; pale brown (10YR 6/3) fine sand, brown (10YR 4/3) moist; single grain; loose, nonsticky and nonplastic; many very fine and fine interstitial pores; 2 percent gravel; very slightly effervescent, slightly alkaline (pH 7.4).
TYPE LOCATION: Lower Red Rock Lake topographic quadrangle, Beaverhead County, Montana; 22 meters north and 675 meters west of the SE corner of section 18, T. 13 S., R. 1 W. UTM: 439002.52E, 4949290.57N - Datum NAD83, Zone 12
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 2 to 5 degrees C
Moisture control section - 30 to 90 cm
Thickness of the mollic epipedon - 25 to 50 cm
A horizon
Value: 3 or 4 dry; 3 moist
Chroma: 2 or 3 dry or moist
Clay content: 2 to 7 percent
Reaction: pH 6.5 to 7.2
Bw horizon
Value: 4 or 5 dry; 3 to 5 moist
Chroma: 2 to 4 dry or moist
Texture: loamy fine sand and fine sand
Clay content: 1 to 4 percent
Rock fragments: 0 to 5 percent gravel
Reaction: pH 6.7 to 7.4
Note: Some pedons may have a BC horizon
C horizon
Hue: 10YR or 2.5Y
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 3 or 4 dry or moist
Texture: fine sand and sand
Clay content: 0 to 2 percent
Rock fragments: 0 to 35 percent gravel
Reaction: pH 6.8 to 7.6
COMPETING SERIES:
Bangston (CO) - have sandstone fragments in the profile
Beeftrail (MT) - moderately deep to paralithic contact
Tomichi (CO) - do not have a Bw horizon
Wissikihon (MT) - deep to paralithic contact
GEOGRAPHIC SETTING:
Landform - dunes, dunefields, and interdunes
Elevation - 2,025 to 2,135 meters
Slope - 1 to 35 percent
Parent materials - eolian sands and alluvium
Climate - long, cold winters; moist springs; cool summers
Mean annual precipitation - 355 to 430 millimeters
Mean annual air temperature - 1 to 4 degrees C
Frost-free period - 50 to 70 days
GEOGRAPHICALLY ASSOCIATED SOILS: none listed.
DRAINAGE AND PERMEABILITY: excessively drained; rapid permeability
USE AND VEGETATION: These soils are used mainly for rangeland. Vegetation is chiefly sagebrush and native grass such as needle-and-thread and Idaho fescue along with Hood's phlox and lupine.
DISTRIBUTION AND EXTENT: The Jackrabbit series is of small extent in the intermountain valleys of southwestern Montana. MLRA 44B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Red Rock Lakes Area - Part of Beaverhead County, Montana, 2012; proposed in Beaverhead County, Montana, 2010.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from the soil surface to 31 cm (A horizon); and a
Particle-size control section - from 25 to 100 cm (part of the A, Bw, and part of the C horizons).
Jackrabbit soils have a cryic temperature regime and an ustic moisture regime.
National Cooperative Soil Survey
U.S.A.