LOCATION LAGALL IDEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Vitrandic Haplocryolls
TYPICAL PEDON: Lagall very gravelly ashy loam, on a 32 percent slope with south aspect at 6600 feet elevation, in a Douglas-fir/common snowberry plant association, woodland. (Colors are for dry soil unless otherwise noted.)
0i--0 to 1 inch; forest litter of needles, leaves, twigs and stems; abrupt smooth boundary. (1 to 4 inches thick)
A1--1 to 8 inches; very dark gray (10YR 3/1) very gravelly ashy loam, black (10YR 2/1) moist; weak very fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine, fine and medium roots, common coarse roots; many very fine irregular and tubular pores; 25 percent pebbles, 5 percent cobbles and 10 percent stones; neutral (pH 6.8); clear smooth boundary. (4 to 10 inches thick)
A2--8 to 16 inches; very dark grayish brown (10YR 3/2) very cobbly ashy loam, very dark brown (10YR 2/2) moist; weak medium subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky and slightly plastic; common very fine through coarse roots; many very fine and fine irregular pores, common very fine tubular pores; 15 percent pebble, 35 percent cobbles and 5 percent stones; neutral (pH 6.8); abrupt smooth boundary. (0 to 10 inches thick)
Bw--16 to 24 inches; pale brown (10YR 6/3) extremely cobbly ashy loam, brown (10YR 4/3) moist; weak fine and medium subangular blocky structure; soft, very friable, slightly sticky and nonplastic; common very fine, fine and medium roots, few coarse roots; many very fine irregular pores, few very fine tubular pores; 35 percent pebbles, 35 percent cobbles and 10 percent stones; neutral (pH 6.6); abrupt wavy boundary. (5 to 40 inches thick)
BC--24 to 62 inches; pale brown (10YR 6/3) extremely cobbly loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common very fine through medium roots; many very fine irregular pores, common very fine tubular pores; 20 percent pebbles, 40 percent cobbles and 20 percent stones; slightly acid (pH 6.4).
TYPE LOCATION: Fremont County, Idaho, about 11 miles north and 5 miles west of Ashton; about 2600 feet north and 1400 feet west of the southeast corner of section 5, T. 10 N., R 42 E.; Latitude- 44 degrees North, 13 minutes, 16 seconds; Longitude - 111 degrees West, 31 minutes, 16 seconds.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 38 to 43 degrees F.
Mean summer soil temperature - 43 to 46 degrees F.
Moisture control section - between 8 and 24 inches. The soil is dry throughout the moisture control section for 30 to 45 consecutive days during the four months following the summer solstice.
Mollic epipedon thickness - 10 to 15 inches
Volcanic glass content - 5 to 30 percent in the 0.2 to 2.0 mm size fraction
Ammonium oxalate extractable Al plus 1/2 Fe - 0.1 to 1.0 percent
Phosphate retention - 20 to 50 percent
A horizons - Hue: 7.5YR or 10YR
Value: 3, 4 or 5 dry; 2 or 3 moist
Chroma: 1, 2 or 3 dry or moist
Texture: ashy loam, ashy silt loam or ashy sandy loam
Clay content: 8 to 16 percent
Rock fragment content: 0 to 70 percent
Pebbles: 0 to 65 percent
Cobbles: 0 to 50 percent
Stones or boulders: 0 to 15 percent
Reaction: pH 6.1 to 7.3
Bw horizon - Hue: 7.5YR or 10YR
Value: 5, 6 or 7 dry; 3, 4 or 5 moist
Chroma: 2, 3 or 4 dry or moist
Texture: ashy loam, ashy silt loam or ashy sandy loam
Clay content: 8 to 18 percent
Rock fragment content: 35 to 90 percent
Pebbles: 15 to 60 percent
Cobbles: 0 to 50 percent
Stones or boulders: 0 to 30 percent
Reaction: pH 6.1 to 7.3
BC horizon - Hue: 10YR or 2.5Y
Value: 5, 6 or 7 dry; 3, 4 or 5 moist
Chroma: 2, 3 or 4 dry or moist
Texture: loam or sandy loam
Clay content: 4 to 12 percent
Rock fragment content: 35 to 90 percent
Pebbles: 5 to 55 percent
Cobbles: 5 to 60 percent
Stones or boulders: 0 to 70 percent
Reaction: pH 6.1 to 7.3
COMPETING SERIES:
Lowland (MT) - have an ustic moisture regime
GEOGRAPHIC SETTING:
Landform - canyons, dissected tablelands, escarpments of plateaus, foothills and mountains
Elevation - 5300 to 8500 feet
Slope - 4 to 70 percent
Parent material - local alluvium or colluvium derived from igneous and sedimentary rocks, loess and volcanic ash
Climate - Cool winters, warm summers. Precipitation is well-distributed throughout the year. A winter snowpack of 3 to 5 feet in depth and lasting through April is common.
Mean annual temperature - 36 to 41 degrees F.
Mean annual precipitation - 18 to 25 inches
Frost free period - 30 to 60 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Koffgo, Povey and Rhylow series. Koffgo and Rhylow soils are in more moist positions on nearby canyons, dissected tablelands, escarpments of plateaus, foothills and mountains. Koffgo soils have an ochric epipedon and Rhylow soils have an umbric epipedon. Povey soils are on slightly warmer and drier positions. They have a mollic epipedon greater than 16 inches thick and a xeric moisture regime.
DRAINAGE AND PERMEABILITY: Well drained, moderate or high runoff, moderate permeability.
USE AND VEGETATION: Lagall soils are used for livestock grazing, recreation, timber production and wildlife habitat. These soils commonly support forested communities dominated by Douglas-fir, subalpine fir or quaking aspen. The potential natural communities are the Douglas-fir/common snowberry plant association and the subalpine fir/mallow ninebark plant association.
DISTRIBUTION AND EXTENT: Southeastern Idaho. They are of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Targhee National Forest, Fremont County, Idaho, 1997.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from the mineral soil surface to 16 inches (A1 and A2 horizons)
Cambic horizon - the zone from 16 to 62 inches (Bw and BC horizons)
Particle-size control section - the zone from 11 to 41 inches (part of the A2, the Bw and part of the BC horizons)
Vitrandic subgroup feature - the zone from the mineral soil surface to 24 inches (A1, A2 and Bw horizons)
Moisture regime - udic
ADDITIONAL DATA: Full Characterization Data (8/96) NSSL, Lincoln, NE.
Client-Assigned Laboratory Number: S94ID-043-007
Project File Number: 95P-27
Laboratory-Assigned Number: Pedon 95P 154
Samples: 95P 1050-1053