LOCATION ELMARK                  MT

Established Series
Rev. PEM/DRS/KLS
01/2023

ELMARK SERIES

The Elmark series consists of moderately deep, well drained soils that formed in colluvium or residuum derived from granite bedrock. These soils are on hills and mountains. Slopes are 8 to 60 percent. Mean annual precipitation is about 430 mm, and mean annual temperature is about 4 degrees C.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Typic Haplustalfs

TYPICAL PEDON: Elmark sandy clay loam, bouldery, in forest (colors are for dry soil unless otherwise noted).

Oe--0 to 5 cm; partially decomposed needles, twigs, and leaves. (1 to 5 cm thick)

A--5 to 13 cm; dark grayish brown (10YR 4/2) sandy clay loam, very dark grayish brown (10YR 3/2) moist; weak medium and fine subangular blocky structure parting to weak fine and very fine granular; soft, very friable, slightly sticky and slightly plastic; many very fine, few fine and few medium roots; many very fine and fine, and few medium pores; 5 percent pebbles; neutral (pH 7.0); clear smooth boundary. (0 to 13 cm thick)

E--13 to 23 cm; light brownish gray (2.5Y 6/2) sandy clay loam, dark grayish brown (2.5Y 4/2) moist; weak medium and fine subangular blocky structure parting to weak fine and very fine granular; soft, very friable, slightly sticky and slightly plastic; many very fine, few fine and few medium roots; many very fine and few fine tubular and interstitial pores; 5 percent pebbles; slightly acid (pH 6.2); clear wavy boundary. (5 to 20 cm thick)

Bt--23 to 53 cm; light yellowish brown (2.5Y 6/4) gravelly sandy clay loam, olive brown (2.5Y 4/4) moist; weak medium prismatic structure parting to moderate medium and fine subangular blocky; slightly hard, friable, sticky and slightly plastic; many very fine, few fine and few medium roots; many very fine and few fine tubular and interstitial pores; many faint clay films bridging sand grains and ped faces; 20 percent pebbles; slightly acid (pH 6.2); gradual wavy boundary. (18 to 58 cm thick)

BC--53 to 81 cm; light olive brown (2.5Y 5/4) gravelly sandy loam, dark grayish brown (2.5Y 4/2), moist; weak medium and fine subangular blocky structure; soft, very friable, slightly sticky and nonplastic; common very fine and few fine roots; many very fine tubular and interstitial pores; 30 percent pebbles; slightly acid (pH 6.1); clear irregular boundary. (0 to 50 cm thick)

Cr--81 to 150 cm; olive (5Y 5/3) decomposed granite bedrock (grus) which crushes to very gravelly loamy coarse sand or gravelly coarse sand, olive gray (5Y 4/2) moist; massive; nonsticky and nonplastic; few very fine roots in upper 3 to 5 cm of horizon; neutral (pH 7.0); gradual smooth boundary. (38 to 76 cm thick)

R--150 cm; hard granite bedrock.

TYPE LOCATION: Jefferson County, Montana; about 380 meters north and 305 meters east of the SW corner of sec. 20, T. 9 N., R. 2 W.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--3 to 6 degrees C
Moisture control section--10 and 30 cm
Depth to argillic horizon--13 to 43 cm
Depth to paralithic contact--50 to 100 cm
Depth to lithic contact--100 to 150 cm
Rock fragments, surface cover--0.01 to 15 percent boulders

A horizon
Hue--10YR or 2.5Y
Value--3 to 5 dry; 2 to 4 moist
Chroma--1 to 3
Texture--coarse sandy loam, sandy loam, sandy clay loam, or loam
Clay content--8 to 25 percent
Rock fragment content--5 to 50 percent total; 5 to 30 percent pebbles, mainly less than 7 mm in diameter; 0 to 20 percent cobbles
Reaction--pH 6.1 to 7.3

E horizon
Hue--10YR or 2.5Y
Value--5 or 6 dry; 4 or 5 moist
Chroma--2 or 3
Texture--coarse sandy loam, sandy loam, or sandy clay loam
Clay content--10 to 25 percent
Rock fragment content--5 to 25 percent pebbles (mostly less than 7 mm in diameter)
Reaction--pH 5.6 to 7.3

Bt horizon
Hue--10YR or 2.5Y
Value--5 or 6 dry; 4 or 5 moist
Chroma--2 to 4
Texture--sandy clay loam or clay loam (less than 2 mm fractions contains a high percentage of coarse sand)
Clay content--20 to 30 percent
Rock fragment content--5 to 25 percent pebbles, mostly less than 7 mm in diameter
Reaction--pH 6.1 to 7.3
Some pedons have Bt1 and Bt2 horizons

BC horizon
Hue--10YR, 2.5Y, or 5Y
Value--5 or 6 dry; 4 or 5 moist
Chroma--2, 3 or 4
Texture--coarse sandy loam or sandy loam
Clay content--10 to 18 percent
Rock fragment content--15 to 35 percent pebbles, mostly less than 7 mm in diameter
Reaction--pH 6.1 to 7.3

Cr horizon
Reaction--pH 6.6 to 7.3

COMPETING SERIES:
Elbeth (CO) - does not have a paralithic or lithic contact above a depth of 150 cm
Northrim (CO) - does not have a paralithic or lithic contact above 150 cm
Zunalei (NM) - does not have a paralithic or lithic contact above 150 cm

GEOGRAPHIC SETTING:
Landform--hills, mountains
Elevation--1350 to 1900 meters
Slope--8 to 60 percent
Parent material--colluvium or residuum derived from granite bedrock
Climate--long, cold winters, moist springs, warm summers
Mean annual precipitation--380 to 480 mm
Mean annual air temperature--2 to 6 degrees C
Frost-free period--70 to 105 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed.

DRAINAGE AND PERMEABILITY: Well drained, moderate permeability in the argillic horizon and moderately rapid below.

USE AND VEGETATION: Elmark soils are primarily used for woodland. The potential native vegetation is mainly Douglas fir, ponderosa pine, pinegrass, common snowberry, white spiraea, Rocky Mountain juniper, big sagebrush, bitterbrush, rough fescue, Idaho Fescue, and bluebunch wheatgrass

DISTRIBUTION AND EXTENT: Elmark soils are of small extent in southwestern Montana; MLRA 43B

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana

SERIES PROPOSED: Jefferson County, Montana, 1993

REMARKS: Soil interpretation record: MT1526, MT3003, MT3027
Diagnostic horizons and features recognized in this pedon are:
A layer of partially decomposed needles, leaves, and twigs--0 to 5 cm (Oe horizon)
Ochric epipedon--5 to 23 cm, mixed (A and E horizons)
Argillic horizon--23 to 53 cm (Bt horizon)
Decomposed granite bedrock (grus)--81 to 150 cm (Cr horizon)
Hard granite bedrock--150 cm (R horizon)
Particle-size control section--23 to 53 cm (Bt horizon)

Elmark soils have a frigid temperature regime and an ustic soil moisture regime.

Classification changed from Eutroboralfs in 1997.

Converted to metric and O horizons were updated to start at zero. Competing series section was not updated. 12/2022

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National Cooperative Soil Survey
U.S.A.