LOCATION TIGERON MT+ID WY
Established Series
Rev. DES/JAL/KLS
07/2022
TIGERON SERIES
The Tigeron series consists of very deep, well drained soils that formed in colluvium or alluvium derived from sandstone, argillite, quartzite, and other igneous rock. These soils are on alluvial fans, hills, and mountains. Slopes are 2 to 60 percent. The mean annual precipitation is about 610 mm, and the mean annual air temperature is about 5 degrees C.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Eutric Haplocryalfs
TYPICAL PEDON: Tigeron flaggy sandy loam, forested (colors are for dry soil unless otherwise noted).
Oe--0 to 3 cm; forest litter of undecomposed and decomposed needles, twigs, and cones.
E1--3 to 11 cm; light brownish gray (10YR 6/2) flaggy sandy loam, very dark grayish brown (10YR 3/2) moist; strong thin platy structure; soft, very friable, nonsticky and nonplastic; many fine and very fine roots; continuous coatings of sand grains on surface of plates; 10 percent flagstones, 5 percent channers; strongly acid (pH 5.4); clear wavy boundary.
E2--11 to 21 cm; light gray (10YR 7/2) flaggy sandy loam, dark grayish brown (10YR 4/2) moist; moderate thin platy structure; slightly hard, very friable, nonsticky and nonplastic; many fine and very fine roots; continuous coatings of sand grains on plates; 20 percent flagstones, 10 percent channers; strongly acid (pH 5.4); clear wavy boundary. (Combined thickness of E horizons - 18 to 45 cm)
E and Bt--21 to 36 cm; E part (75 percent) light gray (10YR 7/2) flaggy sandy loam, grayish brown (10YR 5/2) moist; Bt part (25 percent) pale brown (10YR 6/3) sandy clay loam, brown (10YR 4/3) moist; 2 to 10 mm thick lamellae; moderate fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; many fine and very fine roots; many fine and very fine pores and few medium pores in the E and lamellae; thin clay films in root channels; 20 percent flagstones, 10 percent channers; strongly acid (pH 5.4); clear wavy boundary. (15 to 43 cm thick)
Bt and E--36 to 64 cm; Bt part (60 percent) pale brown (10YR 6/3) very flaggy sandy clay loam, brown (10YR 4/3) moist; 2 to 13 mm thick lamellae; E part (40 percent) light gray (10YR 7/2) sandy loam, dark grayish brown (10YR 4/2) moist; strong fine and very fine blocky structure; very hard, friable, moderately sticky and moderately plastic; common fine and very fine roots; many fine and very fine pores and few medium pores; continuous faint clay films on faces of peds and on undersides of fragments and in root channels; 30 percent flagstones, 15 percent channers; strongly acid (pH 5.4); gradual wavy boundary. (0 to 50 cm thick)
Bt--64 to 158 cm; pale brown (10YR 6/3) extremely flaggy sandy clay loam, brown (10YR 4/3) moist; strong fine and medium blocky structure; extremely hard, friable, moderately sticky and moderately plastic; few fine and very fine roots; many fine and very fine pores and few medium pores; continuous prominent clay films on all faces of peds and in root channels; continuous prominent clay films on all surfaces of smaller fragments and on undersides of larger fragments; common faint coating of sand grains on faces of peds and on surface of fragments; 30 percent flagstones; 30 percent channers; strongly acid (pH 5.4); gradual wavy boundary. (40 to 100 cm thick)
2C--158 to 173 cm; gray (10YR 6/1) very flaggy loam, dark gray (10YR 4/1) moist; massive; extremely hard, friable, moderately sticky and moderately plastic; few fine and very fine roots; common fine and very fine pores; 30 percent flagstones; 20 percent channers; moderately acid (pH 5.6).
TYPE LOCATION: Cascade County, Montana; 40 meters north and 76 meters west of the SE corner of sec. 35, T. 17 N., R. 5 E.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--4 to 8 degrees C
Moisture control section--20 to 60 cm
Depth to argillic horizon--30 to 60 cm
Surface stones or boulders--0 to 3 percent
Some pedons have a thin A horizon, less than 8 cm thick, with mollic colors.
E horizons
Hue--7.5YR or 10YR
Value--6 through 8 dry; 3 through 6 moist
Chroma--2 or 3
Texture--sandy loam or loam
Clay content--10 to 20 percent
Rock fragment content--15 to 65 percent; 0 to 20 percent flagstones and stones, 15 to 45 percent channers
Reaction--pH 5.1 to 6.5
E and Bt horizon
Hue--E part: 7.5YR or 10YR; Bt part: 7.5YR or 10YR
Value--E part: 6 through 8, Bt part: 5 or 6 dry; E part: 3 through 6, Bt part: 4 or 5 moist
Chroma--E part: 2 or 3; Bt part: 2, 3, 4, or 6
Texture--E part: sandy loam or loam, Bt part: sandy loam, loam, clay loam, or sandy clay loam
Clay content--E part: 10 to 22 percent, Bt part: 15 to 35 percent
Rock fragment content--25 to 70 percent; 10 to 25 percent flagstones and stones, 15 to 45 percent channers
Reaction--pH 5.1 to 6.5
Bt and E horizon
Hue--Bt part: 7.5YR or 10YR; E part: 7.5YR or 10YR
Value--Bt part: 5 or 6, E part: 6 through 8 dry; Bt part: 4 or 5, E part: 3 through 6 moist
Chroma--Bt part: 3, 4, or 6; E part: 2 or 3
Texture--Bt part: sandy loam, loam, sandy clay loam, or clay loam; E part: sandy loam or loam
Clay content--Bt part: 15 to 35 percent; E part: 10 to 22 percent. The clay is in thin horizontal bands and small masses or balls.
Rock fragment content--40 to 80 percent; 10 to 30 percent flagstones and flat angular cobbles, 30 to 50 percent flat angular pebbles
Reaction--pH 5.1 to 6.5
Bt horizon
Hue--7.5YR or 10YR
Value--5 through 7 dry; 4 through 6 moist
Chroma--2, 3, 4, or 6
Texture--sandy loam, sandy clay loam, clay loam, or loam
Clay content--15 to 35 percent
Rock fragment content--60 to 85 percent; 20 to 30 percent flagstones and stones, 40 to 55 percent channers
Reaction--pH 5.1 to 6.5
2C horizon
Hue--7.5YR or 10YR
Value--6 or 7 dry, 4 or 5 moist
Chroma--1 through 3
Texture--loam or sandy loam
Clay content--10 to 15 percent
Rock fragment content--50 to 85 percent; 15 to 30 percent flagstones and stones, 35 to 55 percent channers
Reaction--pH 5.1 to 6.5
COMPETING SERIES:
Helmville (MT)--has a horizon of continuous secondary carbonate accumulations
Needleton (CO)--has hue of 5YR and 2.5YR in the argillic horizon
Tamarron (CO)--moderately deep to a paralithic contact
Worock (MT)--does not have a horizon with lamellae
GEOGRAPHIC SETTING:
Landform--alluvial fans, hills, mountains
Elevation--1375 to 2450 meters
Slope--2 to 60 percent
Parent material--colluvium or alluvium derived from sandstone, argillite, quartzite, and other igneous rocks
Climate--long, cold winters
Mean annual precipitation--460 to 760 mm
Mean annual air temperature--2 to 7 degrees C
Frost-free period--30 to 70 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability
USE AND VEGETATION: Tigeron soils are used mainly for timber production. Potential native vegetation is mainly lodgepole pine and Douglas fir, with understory of pinegrass, elk sedge, heartleaf arnica, twinflower, and grouse whortleberry.
DISTRIBUTION AND EXTENT: Tigeron soils are moderately extensive in the mountains of central Montana, northwest Wyoming and southeast Idaho; MLRA 43B and 47
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Cascade County, Montana, 1975
REMARKS: Diagnostic features and horizons recognized in this pedon are:
Albic horizon--3 to 21 cm (E1 and E2 horizons)
Horizons with lamellae--21 to 64 cm (E and Bt, Bt and E horizons)
Argillic horizon--36 to 158 cm (Bt and E horizon and Bt horizon)
Lithologic discontinuity--158 cm
Particle-size control section--36 to 86 cm (Bt and E, part of Bt horizon)
Tigeron soils have a cryic temperature regime and a udic soil moisture regime.
Converted to metric, updated formatting, and O horizons were updated to start at zero. 7/2022
Soil interpretation record--MT0131
National Cooperative Soil Survey
U.S.A.