LOCATION WIDMER ORTentative Series
TAXONOMIC CLASS: Fine, smectitic, mesic Typic Argixerolls
TYPICAL PEDON: Widmer stony loam--on a 4 percent slope at an elevation of 4,220 feet--rangeland. (Colors are for dry soil unless otherwise noted. The soil was dry throughout when it was described on September 16, 1998.)
A--0 to 3 inches; brown (10YR 5/3) stony loam, dark brown (10YR 3/3) moist; weak medium platy structure parting to moderate medium granular; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and few fine roots; common fine and common medium vesicular pores; 10 percent pebbles, 5 percent cobbles, and 7 percent stones; slightly alkaline (pH 7.4); abrupt smooth boundary. (2 to 3 inches thick)
Bt1--3 to 8 inches; grayish brown (10YR 5/2) very cobbly clay loam, very dark grayish brown (10YR 3/2) moist; moderate medium and coarse subangular blocky structure parting to strong medium granular; soft, very friable, slightly sticky and slightly plastic; common very fine, common fine, and few medium roots; common fine and common medium tubular pores; common faint clay films on faces of peds; 15 percent pebbles, 15 percent cobbles and 5 percent stones; slightly alkaline (pH 7.5); clear smooth boundary. (4 to 9 inches thick)
Bt2--8 to 12 inches; brown (10YR 5/3) cobbly clay loam, dark brown (10YR 3/3) moist; moderate medium prismatic structure parting to moderate medium and coarse subangular blocky; slightly hard, friable, slightly sticky and moderately plastic; few very fine, common fine, and few medium roots; common fine and common medium tubular pores; common faint clay films on faces of peds; 10 percent pebbles and 10 percent cobbles; slightly alkaline (pH 7.5); abrupt smooth boundary. (3 to 12 inches thick)
Bt3--12 to 18 inches; light brown (7.5YR 6/3) clay, dark brown (7.5YR 3/4) moist; weak medium prismatic structure parting to moderate medium angular blocky; hard, firm, moderately sticky and moderately plastic; few very fine, few fine, and few medium roots; few very fine and few fine tubular pores; common distinct clay films on faces of peds; slightly alkaline (pH 7.6); gradual smooth boundary. (5 to 10 inches thick)
CBt--18 to 31 inches; pink (7.5YR 7/3) very paragravelly loam, brown (7.5YR 4/4) moist; massive with rock structure; slightly hard, firm, slightly sticky and slightly plastic; few very fine and few fine roots; few very fine and few fine interstitial pores; few faint clay films on pararock fragments; 50 percent parapebbles of weathered vesicular basalt; slightly alkaline (pH 7.8); clear smooth boundary. (6 to 14 inches thick)
Cr--31 to 41 inches; pink (7.5YR 7/4) weathered vesicular basalt, brown (7.5YR 5/4) moist; clear smooth boundary. (8 to 14 inches thick)
R--41 inches; hard vesicular basalt.
TYPE LOCATION: Klamath County, Oregon; in the Willow Valley chaining about 0.75 mile northeast of Malone Dam and 0.3 miles east of the East Langell Valley Road; 2,200 feet north and 850 feet east of the southwest corner of section 17, T. 41 S., R. 14 E.; USGS Langell Valley 7.5 minute topographic quadrangle; 42 degrees 0 minutes 44 seconds north latitude and 121 degrees 12 minutes 33 seconds west longitude, NAD 27.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually moist in winter and spring and dry in summer and fall; xeric moisture regime that borders on aridic.
Mean annual soil temperature - 48 to 50 degrees F.
Mean summer soil temperature - 60 to 62 degrees F.
Mollic epipedon thickness - 7 to 14 inches, includes the Bt1 and Bt2 horizons and may include part of the Bt3 horizon when the upper 7 inches of soil is mixed.
Argillic horizon thickness - 12 to 22 inches.
Depth to base of argillic horizon - 16 to 30 inches.
Depth to bedrock - 20 to 40 inches to a paralithic contact. The paralithic material below the contact is weathered basalt. Hard basalt bedrock is typically within 60 inches.
Particle-size control section - Clay content: 35 to 45 percent; Rock fragments: 5 to 20 percent, mainly pebbles and cobbles. Lithology of fragments is basalt.
Other features - Some pedons have A2 horizons.
A horizon - Value: 5 or 6 dry, 2 or 3 moist; A dry value of 6 is only in some pedons and the upper 7 inches when mixed has a dry value of 5.
Chroma: 2 or 3 dry and moist.
Clay content: 20 to 27 percent.
Rock fragments: 15 to 30 percent.
Reaction: Neutral or slightly alkaline.
Organic matter content: 2 to 4 percent.
Bt1 horizon - Hue: 10YR or 7.5YR.
Value: 5 or 6 dry; A dry value of 6 is only in some pedons and the upper 7 inches when mixed has a dry value of 5.
Chroma: 2 or 3, dry or moist.
Textures: Cobbly clay loam, very cobbly clay loam, or cobbly clay.
Clay content: 35 to 45 percent.
Rock fragments: 15 to 40 percent.
Reaction: Neutral or slightly alkaline.
Organic matter content: 1 to 3 percent.
Bt2 horizon - Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 3 or 4 moist; Dry values of 6 and moist values of 4 are only in some pedons and the upper 7 inches when mixed has a dry value of 5 and moist value of 3.
Chroma: 3 or 4 dry.
Textures: Clay loam, clay, cobbly clay loam, or cobbly clay.
Clay content: 35 to 50 percent.
Rock fragments: 0 to 25 percent.
Organic matter content: 1 to 3 percent.
Bt3 horizon - Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 3 or 4, dry or moist.
Textures: Clay or cobbly clay.
Clay content: 45 to 55 percent.
Rock fragments: 0 to 20 percent.
Reaction: Slightly alkaline or moderately alkaline.
Organic matter content: 1 or 2 percent.
CBt horizon - Value: 7 or 8 dry, 4 through 6 moist.
Chroma: 3 through 6, dry or moist.
Reaction: Slightly alkaline or moderately alkaline.
Pararock fragments: 35 to 60 percent paragravel of weathered basalt.
COMPETING SERIES: These are the Cranegulch (T), Daphnedale, Keating, Maple Hollow, Midvale, and Ramo series. Cranegulch, Maple Hollow, Midvale, and Ramo soils are very deep. Daphnedale soils have paralithic material of tuff in the series control section and do not have horizons formed in residuum containing pararock fragments of weathered basalt. Keating soils are moderately deep to lithic contacts.
GEOGRAPHIC SETTING: Widmer soils are on plateaus. They typically occur on summit positions. These soils formed in residuum derived from basalt. Slopes are 2 to 10 percent. Elevations range from 4,140 to 4,400 feet. The climate is characterized by cold, wet winters and warm, dry summers. The mean annual precipitation is 13 to 15 inches. The mean annual temperature is 46 to 48 degrees F., mean January temperature is 27 to 30 degrees F., and the mean July temperature is 58 to 62 degrees F. The frost-free period is 60 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Lorella, Notchcorral, Wonser, and Woolencanyon soils. Lorella soils are clayey-skeletal and shallow to lithic contacts. Notchcorral soils are fine, moderately deep to thick duripans over bedrock, and have argillic horizons with abrupt textural change. Wonser soils are clayey and shallow to thin duripans over bedrock. Woolencanyon soils have are clayey, shallow to thin duripans over bedrock, and have argillic horizons with abrupt textural change.
DRAINAGE AND PERMEABILITY: Well drained; high surface runoff; slow permeability.
USE AND VEGETATION: Widmer soils are used for livestock grazing, wildlife habitat, and recreation. The native vegetation is western juniper, bluebunch wheatgrass, Idaho fescue, antelope bitterbrush, and basin big sagebrush.
DISTRIBUTION AND EXTENT: Southcentral Oregon. These soils are not extensive. MLRA 21.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES PROPOSED: Klamath County (Gerber Block of Fremont National Forest Area), Oregon 1998. The name is coined.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 12 inches (A1, Bt1, and Bt2 horizons).
Argillic horizon - The zone from 3 to 18 inches (Bt1, Bt2, and Bt3 horizons).
Paralithic contact - The boundary at 31 inches to underlying soft, weathered bedrock (Cr layer).
Particle-size control section - The zone from 3 to 18 inches (Bt1, Bt2, and Bt3 horizons).