LOCATION DINZER OREstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic Typic Haplocryods
TYPICAL PEDON: Dinzer stony fine sandy loam, forested. (Colors are for moist soil unless otherwise noted.)
01--3 1/2 to 1 1/2 inches; needles, leaves, twigs, cones, etc.
02--1 1/2 inches to 0; black (10YR 2/1) and very dark brown (10YR 2/2) amorphous organic matter; many roots; abrupt wavy boundary.
A2--0 to 1/4 inch; dark gray (10YR 4/1) stony fine sandy loam, gray (10YR 6/1) dry; variegated with some dark grayish brown (10YR 4/2); massive; soft, very friable, nonsticky and nonplastic; strongly acid (pH 5.1); abrupt irregular boundary. (0 to 1/2 inch thick)
B2ir--1/4 to 8 inches; dark brown (7.5YR 3/4) stony fine sandy loam, brown (7.5YR 5/4) dry; weak very fine and fine subangular blocky structure; soft, very friable, nonsticky and slightly plastic; many roots; many very fine and fine irregular pores; 40 percent pebbles, cobbles and stones; medium acid (pH 5.8); gradual wavy boundary. (4 to 12 inches thick)
B3ir--8 to 16 inches; brown (7.5YR 4/4) cobbly fine sandy loam, yellowish brown (10YR 5/4) dry; weak very fine and fine subangular blocky structure; soft, very friable, nonsticky and slightly plastic; many roots; many very fine and fine irregular pores; 40 percent rock fragments; medium acid (pH 5.8); clear wavy boundary. (4 to 12 inches thick)
C--16 to 40 inches; dark yellowish brown (10YR 4/4) very cobbly fine sandy loam, yellowish brown (10YR 5/4) dry; massive; soft, friable, nonsticky and slightly plastic; common roots; many very fine and fine irregular pores; 60 percent rock fragments; medium acid (pH 5.6).
TYPE LOCATION: Clackmas County, Oregon; along the new Abbott Road, 1/4 mile east of the junction with the old Abbott Road; NE1/4 SW1/4 section 35, T. 45 S., R. 8 E., W.M.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 40 to 47 degrees F. The mean summer soil temperature is less than 47 degrees F. with an 0 horizon. The soils have an udic moisture regime but have a short dry period of less than 45 consecutive days during the late summer. Depth to bedrock is 60 inches or more. The 10 to 40 inch control section is fine sandy loam or sandy loam and averages less than 10 percent clay and 35 to 70 percent rock fragments, dominantly cobblestones. The thickness of the solum ranges from 12 to 24 inches.
The A2 horizon has value of 3 or 4 moist, 5 through 7 dry and chroma of 1 or 2 moist and dry and is intermittent in occurrence.
The B2ir horizon has value of 3 or 4 moist, 5 through 7 dry and chroma of 3 or 4 moist and dry. It is friable or very friable.
The C horizon has hue of 10YR or 7.5YR, value of 5 or 6 dry and chroma of 3 or 4 moist and dry. Rock fragments commonly increase with increasing depth.
COMPETING SERIES: These are the Evaro, Homestead, Lastance, Mt. Hood and Tenex series. Evaro, Homestead and Tenex soils have drier moisture regimes than udic. Also, Evaro soils have A2 horizons 5 to 15 inches thick and have slightly acid to mildly alkaline C horizons and Homestead soils have a thin loess mantle. Lastance soils have continuous A2 horizons up to 3 inches thick, upper Bir horizons with hue of 5YR or 2.5YR and firm consistence. Mt. Hood soils have continuous A2 horizons up to 4 inches thick and highly variegated Bir horizons with hue of 10YR through 5YR.
GEOGRAPHIC SETTING: Dinzer soils are on ridges and hillsides in glaciated valleys of the Cascade Mountains at elevations of 3,000 to 5,000 feet. Slope gradients range from 5 to 60 percent. The soils formed in glacial till weathered mostly from andesitic and basaltic rocks of Pleistocene and Pliocene age. The climate is humid and cool. The mean annual precipitation ranges from 55 to 90 inches. The mean annual temperature is 40 to 45 degrees F., the average January temperature is 29 degrees F., and the average July temperature is 57 degrees F. The frost-free season is less than 50 days. GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Lastance soils and the Oneonta soils. Oneonta soils have umbric epipedons and lack spodic horizons.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderately rapid permeability.
USE AND VEGETATION: Timber production, recreation and wildlife. Vegetation is Douglas-fir, western hemlock, mountain hemlock, noble fir, silver fir, western white pine, huckleberry, rhododendron and beargrass.
DISTRIBUTION AND EXTENT: Cascade Mountains of northern Oregon. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Clackamas County, Oregon (Bull Run-Sandy Area), 1968.
ADDITIONAL DATA: Characterization data for one pedon (FS63-Oreg-048-9, 1-4) by Oregon State University. Unpublished.
NSTH 17, RECLASSIFICATION ONLY, 3/95