LOCATION LENZ ID+WA
Established Series
Rev. PMH/RWL/RJS
10/2016
LENZ SERIES
The Lenz series consists of moderately deep, well-drained soils formed in material weathered from gneiss, schist, and granite, with small amounts of loess and volcanic ash in the upper part. These soils are on mountain and foothill side slopes. Slopes range from 3 to 65 percent. The mean annual precipitation is about 28 inches and mean annual temperature is about 47 degrees F.
TAXONOMIC CLASS: Loamy-skeletal, isotic, mesic Vitrandic Haploxerolls
TYPICAL PEDON: Lenz ashy loam - on a southwest-facing slope of 42 percent, forested, at 3,800 feet elevation. (Colors are for dry soil unless otherwise stated. When described the soil was slightly moist.)
A--0 to 7 inches; dark brown (10YR 3/3) ashy loam, very dark brown (10YR 2/2) moist; moderate medium and coarse granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine, fine, medium and few coarse roots; many very fine and fine interstitial pores; 5 percent fine gravel; slightly acid (pH 6.4); clear wavy boundary. (7 to 10 inches thick)
BA--7 to 12 inches; brown (10YR 5/3) ashy loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure parting to moderate fine and medium granular; soft, very friable; slightly sticky and slightly plastic; many very fine and fine, common medium, and few coarse roots; many very fine and fine interstitial pores; 10 percent fine gravel; slightly acid (pH 6.2); clear wavy boundary. (0 to 8 inches thick)
Bt--12 to 23 inches; light yellowish brown (10YR 6/4) very gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine, few medium and coarse roots; common very fine and fine tubular and interstitial pores; few faint clay films in pores; 25 percent gravel and 10 percent cobbles; slightly acid (pH 6.3); clear wavy boundary. (5 to 17 inches thick)
C--23 to 36 inches; light yellowish brown (10YR 6/4) extremely stony sandy loam, dark yellowish brown (10YR 4/4) moist; single grain; loose; few very fine and fine roots; common fine interstitial and few fine tubular pores; 75 percent stones; moderately acid (pH 6.0); gradual wavy boundary. (5 to 14 inches thick)
R--36 inches; fractured granite bedrock with few fines in cracks.
TYPE LOCATION: Kootenai County, Idaho; about 1,000 feet east from junction of main Mica Peak road with Idaho State Forest Road M30; 20 feet above the road; about 2,000 feet east and 650 feet north of the southwest corner, section 28, T. 50 N., R. 5 W. Latitude - 47 degrees, 38 minutes, 44 seconds North; Longitude - 116 degrees, 58 minutes, 17.5 seconds West. NAD 83. USGS topographic quadrangle - Post Falls, ID.
RANGE IN CHARACTERISTICS:
Depth to bedrock (lithic contact) - 20 to 40 inches
Moisture control section (6 to 24 inches)
moist - November to July (60 to 90 consecutive days)
dry - July to October
Mean annual soil temperature - 47 to 50 degrees F
Particle-size control section - average 8 to 12 percent clay
Base saturation - 50 to 75 percent in some or all parts of the soil above 30 inches or lithic contact
Volcanic ash influence - 10 to 18 inches
Estimated properties of ash influenced layer:
Volcanic glass content - 5 to 25 percent
Acid oxalate Al + 1/2Fe - 0.4 to 1.0 percent
Moist bulk density - 1.0 to 1.2 g/cc
15-bar water retention - 5 to 10 percent (air-dried)
Surface stoniness - 0 to 3 percent
Reaction (soil profile) - neutral to moderately acid
A horizon
Value - 3 to 5 dry, 2 or 3 moist
Chroma- 1 to 3, dry or moist
Texture - ashy loam or ashy sandy loam, and some pedons are gravelly, very gravelly, stony, or very stony
Clay content - 8 to 20 percent
Rock fragments - 5 to 50 percent
Bt or Bw horizon
Hue - 10YR or 7.5YR
Value - 5 to 7 dry, 3 to 5 moist
Chroma - 3 or 4, dry or moist
Texture - very gravelly sandy loam, very gravelly ashy sandy loam, very gravelly loam, very cobbly sandy loam, very stony sandy loam, very stony loam, extremely cobbly sandy loam, or extremely cobbly loam
Clay content - 6 to 20 percent
Rock fragments - 35 to 75 percent
C horizon
Value - 5 to 7 dry, 3 to 5 moist
Chroma - 3 or 4, dry or moist
Texture - very gravelly, extremely gravelly, very cobbly, extremely cobbly, or extremely stony sandy loam
Clay content - 4 to 10 percent
Rock fragments - 40 to 80 percent
An O horizon is present in some pedons.
COMPETING SERIES: These are the
Borgeau,
Emily,
Garrison,
Louiecreek,
Opportunity,
Raisio,
Sinlahekin,
Speigle,
Vanbrunt, and
Whitestone series. Borgeau, Emily, Garrison, Louiecreek, Opportunity, Sinlahekin, Speigle, and Whitestone soils are more than 40 inches to bedrock. Raisio soils are dominated by 35 to 80 percent channers and flagstones. Vanbrunt soils have less than 8 percent clay and do not have stones in the particle-size control section
GEOGRAPHIC SETTING: Lenz soils are on southeast to southwest-facing mountain and foothill side slopes at elevations of 1,700 to 4,000 feet. The slopes range from 3 to 65 percent. The soils formed in colluvium and residuum weathered from granite, gneiss, or schist, with small amounts of loess and volcanic ash mixed in the upper part of the profile. The mean annual temperature ranges from 46 to 49 degrees F. The mean annual precipitation ranges from 18 to 35 inches. The frost-free season is 90 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Ardtoo,
Kruse,
Molly,
Schumacher,
Skalan,
Spokane, and
Ulricher soils. Ardtoo soils have a frigid soil temperature regime, are over 40 inches to bedrock and are on back slopes of mountains. Molly and Ulricher, soils have ochric epipedons, are not skeletal and are on back slopes of mountains. Kruse and Skalan soils have argillic horizons, ochric epipedons and are on footslopes of mountains. Schumacher soils have argillic horizons and are on footslopes of mountains. Spokane soils are coarse-loamy and are on back slopes of mountains.
DRAINAGE AND PERMEABILITY: Well-drained. Runoff is medium to very rapid. Saturated hydraulic conductivity is moderately high in the upper part of and high in the lower part.
USE AND VEGETATION: These soils are used mainly for grazeable woodland, wildlife habitat, recreation, and watershed. Potential natural vegetation is mainly Douglas-fir and ponderosa pine with an understory of common snowberry, mallow ninebark, creambush oceanspray, pine reedgrass, and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: Northern Idaho and eastern Washington; MLRA 43A. These soils are moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Kootenai County, Idaho, 1976.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Mollic epipedon - the zone from 0 to 12 inches (A and BA horizons)
Cambic horizon - the zone from 12 to 23 inches (Bt horizon)
Vitrandic feature - the zone from 0 to 12 inches (A and BA horizons)
Ultic feature - the zone from 10 to 30 inches having a base saturation (sum) of less than 75 percent in one or more horizons
Lithic contact - the zone beginning at 36 inches (R)
Particle-size control section - the zone from 10 to 36 inches
Classification revised 11/01 based on assumed ash influence of the surface and the associated soils in Kootenai and Spokane counties currently classified as Vitrandic subgroups.
Lenz soils should be further investigated to determine typical mineralogy (isotic vs. mixed).
National Cooperative Soil Survey
U.S.A.