LOCATION LOZEAU             MT 
Established Series
Rev. MJH-GLS-RJS
09/2008

LOZEAU SERIES


The Lozeau series consists of moderately deep, well drained soils that formed in colluvium and residuum derived from semi-consolidated welded tuff. These soils are on mountain slopes and escarpments. Slopes are 8 to 50 percent. The mean annual precipitation is about 23 inches, and the mean annual temperature is about 42 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, active, frigid Glossic Hapludalfs

TYPICAL PEDON: Lozeau gravelly loam, forested. (Colors are for dry soil unless otherwise noted.)

Oi--0 to 1 inch; undecomposed and partially decomposed forest litter. (1 to 2 inches thick)

A--1 to 4 inches; grayish brown (10YR 5/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium granular structure; soft, very friable, slightly sticky and slightly plastic; common very fine, fine and medium roots; 20 percent gravel; moderately acid (pH 6.0); clear smooth boundary. (3 to 6 inches thick)

E/Bw--4 to 17 inches; E part (65 percent) is light brownish gray (10YR 6/2) gravelly loam, grayish brown (10YR 5/2) moist; B part (35 percent) is pale brown (10YR 6/3) gravelly loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; few very fine and common fine and medium roots; few fine and medium tubular pores; 20 percent gravel; moderately acid (pH 6.0); clear smooth boundary. (7 to 14 inches thick)

Bt/E--17 to 33 inches; Bt part (65 percent) is light yellowish brown (10YR 6/4) gravelly clay loam, dark yellowish brown (10YR 4/4) moist; E part (35 percent) is very pale brown (10YR 7/3) gravelly loam, brown (10YR 5/3) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, moderately sticky and slightly plastic; few fine and common medium roots; common fine tubular pores; common faint clay films on faces of peds and in pores; 15 percent gravel, 5 percent cobbles and 15 percent paragravel; slightly acid (pH 6.2); gradual smooth boundary. (10 to 20 inches thick)

Cr--33 to 60 inches; semi-consolidated welded tuff.

TYPE LOCATION: Sanders County, Montana. 2,600 feet east, 3,450 feet north of the SW corner of sec. 5, T. 24 N., R. 24 W.

RANGE IN CHARACTERISTICS:

Soil temperature - 41 to 43 degrees F.
Moisture control section - between 4 and 12 inches.
Depth to Cr horizon - 20 to 40 inches.
Some profiles have an E and/or BC horizon.

A horizon - Value: 5 or 6 dry; 3 or 4 moist
Chroma: 2 or 3
Clay content: 10 to 27 percent
Rock fragments: 15 to 35 percent - 15 to 30 percent gravel; 0 to 5 percent cobbles
Reaction: pH 5.6 to 6.5
When mixed to 7 inches the surface fails to meet the requirements of a mollic epipedon.

E/Bw horizon - Hue: 10YR, 2.5Y
Value: E part - 6 or 7 dry, 5 or 6 moist; B part - 5 or 6 dry, 4 or 5 moist
Chroma: E part - 2 or 3; B part - 3 or 4
Clay content: 10 to 27 percent
Rock fragments: 10 to 35 percent - 10 to 30 percent gravel; 0 to 5 percent cobbles
Reaction: pH 5.6 to 6.5

Bt/E horizon - Hue: 10YR, 2.5Y
Value: B part - 5 or 6 dry, 4 or 5 moist; E part - 6 or 7 dry, 5 or 6 moist
Chroma: B part - 3, 4 or 6; E part - 2 or 3
Texture: loam, clay loam, sandy clay loam
Clay content: 20 to 35 percent
Rock fragments: 5 to 60 percent - 0 to 5 percent cobbles; 5 to 30 percent gravel; 0 to 25 paragravel
Reaction: pH 5.6 to 6.5

COMPETING SERIES:

There are no competing series.

GEOGRAPHIC SETTING:

Landform- mountain slopes and escarpments.
Slope - 8 to 50 percent.
Elevation - 3,000 to 4,400 feet.
Parent material - colluvium and residuum derived from semi-consolidated welded tuff.
Climate - long, cold winters; moist springs; hot, dry summers.
Mean annual precipitation - 22 to 26 inches, most of which falls as snow and spring rains.
Mean annual temperature - 39 to 43 degrees F.
Frost-free period - 70 to 90 days.

GEOGRAPHICALLY ASSOCIATED SOILS:

DRAINAGE AND PERMEABILITY: Well drained, moderately slow permeability.

USE AND VEGETATION: Lozeau soils are used for understory grazing and as woodland. Native overstory includes ponderosa pine, Douglas-fir and western larch with an understory including pinegrass, dwarf huckleberry, kinnikinnick, and white spirea.

DISTRIBUTION AND EXTENT: Lozeau soils are of small extent in the intermountain valleys of northwestern Montana. MLRA 43A.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Sanders County, Montana, 1997.

REMARKS: Diagnostic horizons and other features recognized in this pedon are:
Ochric epipedon - 0 to 17 inches (A and E/Bw horizons);
Argillic horizon with tongues of albic material - 17 to 33 inches (Bt/E horizon);
Paralithic contact - at 33 inches (Cr horizon);
Particle size control section - 17 to 33 inches (Bt/E horizon).

Lozeau soils have a frigid temperature regime and an udic moisture regime.

Soil interpretation record MT1216.


National Cooperative Soil Survey
U.S.A.