LOCATION LEMAH WATentative Series
TAXONOMIC CLASS: Ashy-skeletal, amorphic Typic Vitricryands
TYPICAL PEDON: Lemah extremely stony ashy sandy loam under a coniferous forest on a 61 percent northeast-facing slope at an elevation of 2,800 feet. The soil was dry when described. (Colors are for dry soil unless otherwise stated.)
0e--0 to 0.5 inches; partially decomposed forest litter. (0 to 1 inch thick)
A--0.5 to 3 inches; grayish brown (10YR 5/2); extremely stony ashy sandy loam (volcanic ash from Mt. St. Helens Y), very dark grayish brown (10YR 3/2) moist; single grain; loose; nonsticky and nonplastic; common very fine and fine roots; 10 percent gravel, 20 percent cobbles and 15 surface stones; moderately acid (pH 5.6); abrupt wavy boundary. (2 to 6 inches thick)
Bw1--3 to 9 inches; yellowish brown (10YR 5/6); very cobbly ashy sandy loam, dark yellowish brown (10YR 4/6) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic, weakly smeary; common very fine, fine, and few medium roots; 15 percent gravel, 30 percent cobbles, and 5 percent stones; NaF pH 12.0; moderately acid (pH 5.6); clear wavy boundary. (5 to 8 inches thick)
Bw2--9 to 21 inches; yellowish brown (10YR 5/4) very cobbly ashy sandy loam, dark yellowish brown (10YR 3/6) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; weakly smeary; common very fine and fine roots; 20 percent gravel, 35 percent cobbles, and 5 percent stones; NaF pH 12.0; moderately acid (pH 5.6); gradual wavy boundary. (7 to 13 inches thick)
BC--21 to 37 inches; light yellowish brown (10YR 6/4); extremely cobbly ashy sandy loam, dark yellowish brown (10YR 3/4) moist, weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic, weakly smeary; common very fine and fine roots; 30 percent gravel, 35 percent cobbles, and 5 percent stones; NaF pH 12.0; moderately acid (pH 6.0); clear wavy boundary. (5 to 16 inches thick)
C--37 to 60 inches; light yellowish brown (2.5Y 6/4), extremely cobbly ashy sandy loam; olive brown (2.5Y 4/4) moist; single grain; loose; nonsticky and nonplastic; few very fine roots; 40 percent gravel and 30 percent cobbles, NaF pH 12.0; moderately acid (pH 6.0).
TYPE LOCATION: Kittitas County, Washington; about 3 miles northwest of Salmon la Sac along the Waptus River Trail, 150 feet east and 2,100 feet north of the southwest corner sec. 32 T. 23 N., R. 14 .
RANGE IN CHARACTERISTICS: The average annual soil temperature ranges from 44 to 46 degrees F. The soils are usually moist but are dry in all parts of the moisture control section for 30 to 45 consecutive days during summer and fall. Solum thickness ranges from 26 to 40 inches. The particle-size control section has 30 to 60 percent volcanic glass, acid oxalate extractable Al plus Fe of 2.0 to 3.0 percent, 15-bar moisture of 10 to 12 percent, and a moist bulk density of 0.85 to 1.10 g/cc; dominated by rock fragments of gabbro, diabase, and serpentized Teanaway basalt origin.
The A horizon has a chroma of 2 or 3 moist. Soil reaction is moderately acid or slightly acid.
The Bw horizon has value of 5 or 6 dry, 3 or 4 moist, and chroma of 4 or 6 moist. Texture is very cobbly or extremely cobbly ashy sandy loam and averages 20 to 40 percent gravel, 25 to 35 percent cobbles, and 0 to 5 percent stones.
The C horizon has hue of 10YR or 2.5Y, value of 6 or 7 dry. It averages 20 to 40 percent gravel, 30 to 50 percent cobbles, and 0 to 5 percent stones.
COMPETING SERIES: These are the Domerie (T), Douthit, Esmeralda, Jimek (T), and Sunnotch series.
Domerie soils - 40 to 60 inches to lithic bedrock (phyllite); pscs dominated with channer and flagstone rock fragments.
Douthit soils - 10 to 20 inches to glacial till; solum depth of 10 to 20 inches.
Esmeralda soils - mean annual soil temperature of 40 to 42 degrees F.; spodic horizon 6 to 11 inches thick and within upper part of pscs.
Jimek soils - 20 to 40 inches to lithic bedrock (rhyolite); mean annual soil temperature of 39 to 43 degrees F.
Sunnotch soils - mean annual soil temperature of 39 to 43 degrees F.; pscs has 60 to 90 percent volcanic glass and 5 to 35 percent cinders.
The Longjohn series is in a similar glassy mineralogy and has 4 to 8 percent 15-bar moisture.
GEOGRAPHIC SETTING: Lemah soils are on mountain side slopes and have slopes of 60 to 90 percent. Elevation ranges from 2,700 to 4,000 feet. The soils developed in colluvium from hard Swauk sandstone mixed with volcanic ash. Rock fragments are angular light gray (5Y 7/1) fresh face quartz sandstone with a pale yellow (2.5Y 7/4) weathering rhine. It can barely be chipped by a rock hammer. The soils are in a marine influenced climate with cool, dry summers and cool, wet winters. The mean annual precipitation is 50 to 80 inches. The mean January temperature is about 26 degrees F, and the mean July temperature is about 61 degrees F. The mean annual temperature is about 43 degrees F. The growing season at 28 degrees F. is 130 to 170 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Polallie soils. The Polallie soils are 20 to 40 inches to a lithic contact and are on mountain side slopes.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is medium to rapid. Permeability is rapid.
USE AND VEGETATION: These soils are used for timber production, wildlife habitat, and watershed. Vegetation is Douglas-fir, mountain hemlock, western hemlock, western white pine and lodgepole pine with an understory of Oregon-grape, pachystima, huckleberry, princes pine, and pyrola.
DISTRIBUTION AND EXTENT: East slopes of the Cascade Mountains in northwestern Kittitas County; MLRA 3. This series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Kittitas County, Washington, l981.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
ochric epipedon - from the mineral surface to 3 inches
cambic horizon - from 3 to 21 inches
andic soil properties - from 0.5 to 60 inches and estimated from similar soils
pscs - from 0.5 to 40.5 inches