LOCATION HELMER                  WA

Established Series
Rev. CJW/BDG/EMM
11/2012

HELMER SERIES

The Helmer series consists of soils that are very deep, well and moderately well drained, and are on hills and ridges. They formed in loess overlying basalt and have a thick mantle of volcanic ash. Slopes are 3 to 60 percent. The average annual precipitation is about 32 inches and average annual air temperature is about 45 degrees F.

TAXONOMIC CLASS: Ashy over loamy, amorphic over mixed, superactive, frigid Alfic Udivitrands

TYPICAL PEDON: Helmer ashy silt loam, forest; on a northwest slope at 3,900 feet. (Colors are for dry soil unless otherwise noted.)

Oi--0 to 3cm; loose litter of pine needles and small twigs.

Oe--3 to 5cm; partially decomposed forest litter; slightly acid.

A--5 to 10cm; dark-brown (7.5YR 4/4) ashy silt loam, darker brown
(7.5YR 3/2) moist; weak, very fine, granular structure; soft, very friable; pH 6.5; clear smooth boundary. ranges from 0 to 5 cm thick; occasionally replaced by a thin (1 cm) gray A2 layer.

Bw1--10 to 30cm; yellowish-brown (10YR 5/4) ashy silt loam, dark
brown (7.5YR 3/4) moist; weak to moderate, fine granular structure; soft, very friable, nonplastic, and nonsticky; abundant roots; pH 6.5; gradual, wavy boundary.

Bw2--30 to 58cm; light yellowish-brown (10YR 6/4) ashy silt loam, dark brown (7.5YR 4/4) moist; weak, medium, granular structure; soft, very friable, nonsticky, and nonplastic; abundant roots; pH 6.4; abrupt, wavy boundary. (Combined thickness of Bw horizons is 38 to 65cm)

2E--58 to 60cm; light brownish-gray (10YR 6/2) silt loam, grayish brown (10YR 5/2) moist; few, fine, faint mottles; massive to very weak, coarse, granular structure; hard, firm, nonplastic, and nonsticky; plentiful roots; pH 6.2; clear, irregular boundary. (0 to 20cm thick)

2E/Btb--60 to 85cm; the E part is similar to the E layer above; the Btb is dark yellowish-brown silt loam (10YR 3/4) moist; few, fine, faint mottles; weak, medium, prismatic to weak, coarse, subangular blocky structure; hard, firm, slightly plastic, and slightly sticky; few manganese concretions; thin patchy clay films on ped surfaces of Btb; pH 6.2; gradual, wavy boundary.

2Btb/E--85 to 115cm; similar to above layer, but the Btb is dominant over the E; gradual, wavy boundary. (Combined thickness of 2E/B and 2B/E horizons is 28 to 55cm)

2Btb--115 to 185cm; yellowish-brown (10YR 5/4) silty clay loam, darker yellowish brown (10YR 3/4) moist; few, fine, distinct mottles; moderate, medium, subangular blocky structure; hard, firm, plastic, and sticky; few roots; few light-gray coats an peds; continous clay films on faces of peds and in pores; numerous concretions of manganese; pH 6.0; abrupt, smooth boundary.

3R--185cm; fractured basalt bedrock.

TYPE LOCATION: Walla Walla County, Washington; about 12 miles east of Walla Walla, Washington; about 525m north and 600m west of the southeast corner of section 14, T. 7 N., R. 38 E.; Latitude - 46 degrees, 4 minutes, 51.9 seconds North; Longitude - 118 degrees, 1 minute, 8.1 seconds West; USGS Kooskooskie Quadrangle.

RANGE IN CHARACTERISTICS:

Soil moisture - usually dry for 30 to 45 consecutive days in August through mid-September, moist in the fall through early summer.
Average annual soil temperature - 42 to 46 degrees F.
Average summer soil temperature - 47 to 49 degrees F., with an O horizon.
Depth to seasonal perched water table - 12 to 18 inches, February to April.

Volcanic ash mantle - 20 to 30 inches thick
Volcanic glass content in the 0.02 to 2.0 mm fraction - 40 to 60 percent
Acid-oxalate extractable Al plus 1/2 Fe - 1.0 to 2.0 percent
Phosphate retention - 60 to 70 percent
15-bar water retention on air dried samples - 7 to 12 percent

A horizon - absent in some pedons
Hue - 7.5YR or 10YR
Value - 4 to 6 dry and 3 or 4 moist
Chroma - 3 or 4 dry and 1 to 4 moist
Texture - ashy silt loam or ashy loam
Clay content - 6 to 10 percent
Bulk density - 0.70 to 0.85 g/cc
Reaction - 5.6 to 7.3

Bw horizon
Hue - 10YR or 7.5YR
Value - 5 or 6 dry and 3 to 5 moist
Chroma - 3 or 4 dry and 3 to 6 moist
Texture - ashy silt loam or ashy loam
Clay content - 6 to 10 percent
Bulk density - 0.70 to 0.85 g/cc
Reaction - 5.6 to 7.3

2E horizon - Present in some pedons
Value - 6 or 7 dry and 4 or 5 moist
Chroma - 1 or 2 moist
Texture - very fine sandy loam, ashy very fine sandy loam, ashy loam, ashy silt loam, or silt loam
Clay content - 8 to 18 percent
Bulk density - 1.10 to 1.45 g/cc
Reaction - 5.6 to 7.3

2E/Btb and 2Btb/E horizons
E part
Value - 5 to 7 dry and 4 to 6 moist
Chroma - 2 or 3 dry and 2 to 4 moist
Texture - silt loam
Clay content - 8 to 18 percent

B part
Value - 5 or 6 dry and 3 to 5 moist
Texture - silt loam or silty clay loam
Clay content - 18 to 35 percent
Rock fragments - 0 to 20 percent gravel, 0 to 15 percent cobbles, 0 to 20 percent total rock fragment content
Bulk density - 1.10 to 1.45 g/cc
Reaction - 5.6 to 7.3

2Btb horizon
Hue - 10YR or 7.5YR
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 3 to 6 dry,3 or 4 moist
Texture - silt loam, silty clay loam, or clay loam
Clay content - 25 to 35 percent
Rock fragments - 0 to 18 percent gravel, 10 to 25 percent cobbles, 10 to 30 percent total rock fragment content
Bulk density - 1.20 to 1.40 g/cc
Reaction - 5.6 to 7.3

COMPETING SERIES: These are the Brodeer, Chesley(T), Cranberry, Disalto(T), Dworshak, and Scand series.

Brodeer soils: do not have buried horizons, do not have albic materials or glossic horizons; are formed in colluvium and residuum from metamorphic rocks with a mantle of volcanic ash.

Chesley(T) soils: are deep to a paralithic contact; have 3BC and 3C horizons; are formed in loess and material from fine grained quartzite or siltites of the Belt Supergroup with a volcanic ash mantle.

Cranberry soils: have 3Btb horizons, do not have albic materials or glossic horizons, are formed in loess over basalt residuum with a volcanic ash mantle.

Disalto(T) soils: have 3BC and 3C horizons, do not have albic materials or glossic horizons, are formed in loess over material from quartzite and phyllite with a volcanic ash mantle.

Dworshak soils: have 3Bt horizons with >15 percent metamorphic rock fragments, are formed in loess over residuum from metamorphic rock with a mantle of volcanic ash.

Scand soils: do not have albic materials or glossic horizons, have 3Bt horizons with 30 to 50 percent mica content, are formed in loess over mica schist with a mantle of volcanic ash.

GEOGRAPHIC SETTING: Helmer soils are on hills and ridges. Slopes range from 3 to 60 percent. Elevations range from 3,000 to 5,000 feet. The soils formed in thick loess deposits that may be over basalt, and have a thick mantle of volcanic ash. The average annual precipitation is 35 to 53 inches and average annual air temperature is 43 to 45 degrees F. The frost-free season is 30 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Couse, Gwin and Klicker soils. Couse soils are on plateaus and structural benches. They have a thick dark surface and only minor amounts of volcanic ash. They are moderately well drained. Gwin soils are on plateaus, ridges, foothills and canyons. They are shallow to bedrock, have more than 35 percent rock fragments and have a mesic temperature regime. Klicker soils are on mountains, plateaus, canyons and structural benches. They are moderately deep to bedrock, and have more than 35 percent rock fragments.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; medium to very rapid runoff; moderately high saturated hydraulic conductivity

USE AND VEGETATION: These soils are used for timber production, livestock grazing, wildlife habitat, and recreation. A few areas are used for hay and pasture, and home sites. Potential natural vegetation is mainly grand fir, western larch, Douglas-fir, ponderosa pine and lodgepole pine, with and understory of heartleaf arnica, kinnikinnik, elk sedge, pinegrass, peavine and common snowberry.

DISTRIBUTION AND EXTENT: Eastern Washington. The series is moderately extensive. MLRA 43C.

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

SERIES ESTABLISHED: Latah County, Idaho, 1915.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Andic soil properties - the zone from 5 to 58cm (A, Bw1 and Bw2 horizons)

Ochric epipedon - the zone from the soil surface to 10cm (Oi, Oe and A horizons)

Cambic horizon - the zone from 10 to 58cm (Bw1 and Bw2 horizons)

Argillic horizon - the zone from 85 to 115cm (2Btb/E and 2Btb horizons)

Albic materials - the zone from 58 to 115cm (2E, 2E/Btb and 2Btb/E horizons)

Glossic feature - the zone from 60 to 115cm (2E/Btb and 2Btb/E horizons)

Particle-size control section - the zone from 5 to 105cm (A,Bw1, Bw2, 2E, 2E/Btb and part of 2Btb/E horizons)

Helmer series has been replaced throughout its former extent in northern Idaho and generally correlates to the Threebear series. The type location was moved to Walla Walla County. This is the last survey area where the Helmer series is in use. The series concept has been modified to match the concept used in the Walla Walla County soil survey. The original concept of Helmer included a fragipan at 14 to 20 inches from the soil surface. Further investigation is needed to characterize the series in MLRA 43C.

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National Cooperative Soil Survey
U.S.A.