LOCATION TUMALO OREstablished Series
TAXONOMIC CLASS: Ashy, glassy, mesic Duric Vitritorrands
TYPICAL PEDON: Tumalo ashy sandy loam - rangeland, on a 1 percent slope at 3300 feet elevation. (When described (6/30/86), the soil was dry throughout. Colors are for dry soil unless otherwise noted.)
A1-- 0 to 3 inches; dark grayish brown (10YR 4/2) ashy sandy loam, very dark brown (10YR 2/2) moist; weak fine granular structure; slightly hard, friable, nonsticky and nonplastic; many very fine and fine roots; many very fine and fine interstitial pores; 10 percent gravel; neutral (pH 7.0); clear smooth boundary.
A2-- 3 to 10 inches; grayish brown (10YR 5/2) ashy sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common very fine and fine roots; common very fine and fine interstitial pores; 10 percent gravel; neutral (pH 7.2); clear smooth boundary. (Combined thickness of the A horizon is 7 to 14 inches)
AB-- 10 to 18 inches; grayish brown (10YR 5/2) ashy sandy loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common very fine and fine roots; common very fine and fine interstitial pores; 10 percent gravel; slightly alkaline (pH 7.4); abrupt smooth boundary. (5 to 10 inches thick)
Bw-- 18 to 32 inches; pale brown (10YR 6/3) very gravelly ashy sandy loam, dark brown (10YR 3/3) moist; moderate medium and coarse subangular blocky structure; hard, friable, nonsticky and nonplastic; common very fine and fine, few medium roots; common very fine and fine interstitial pores; 35 percent gravel; slightly alkaline (pH 7.4); abrupt wavy boundary. (8 to 20 inches thick)
2Bkqm-- 32 to 44 inches; very pale brown (10YR 7/4) duripan, indurated; very hard; laminar capping on surface and in fractures over strongly cemented gravel; strongly effervescent; moderately alkaline (pH 8.4); abrupt wavy boundary.
3C-- 44 to 90 inches; black (10YR 2/1) and very pale brown (10YR 7/3) extremely gravelly sand, black (10YR 2/1) and pale brown (10YR 6/3) moist; single grain; loose, nonsticky and nonplastic; 70 percent gravel; neutral (pH 7.2).
TYPE LOCATION: Deschutes County, Oregon; 1600 feet north and 900 feet east of the SW corner of section 30, T. 16 S., R. 12 E. (Latitude 44 degrees, 9 minutes, 00 seconds N, Longitude 121 degrees, 20 minutes, 30 seconds W)
RANGE IN CHARACTERISTICS: These soils are usually dry and are dry in all parts of the soil moisture control section for 120 to 150 days (cumulative). The mean annual soil temperature is 48 to 52 degrees F. Depth to the indurated duripan is 20 to 40 inches. Depth to bedrock is greater than 60 inches. The pumice content (0.5 to 2.0 mm.) of the solum ranges from 20 to 60 percent. The solum contains 50 to 80 percent glass and glass-coated aggregate, a phosphate retention of 25 to 60 percent, acid oxalate extractable aluminum plus one-half the acid oxalate iron of 0.4 to 0.6 percent and a 15-bar water content of 5 to 12 percent on both dried and undried samples. The mollic epipedon is 7 to 14 inches thick. The solum contains 5 to 10 percent clay and 55 to 75 percent sand.
The A horizon has value of 4 or 5 dry, 2 or 3 moist, and chroma of 1 or 2 dry and moist. It is sandy loam and contains 0 to 10 percent gravel and 0 to 15 percent cobbles and stones. Total rock fragment content is 0 to 15 percent.
The Bw horizon has value of 5 or 6 dry, 3 or 4 moist and chroma of 2 or 3 dry and moist. It is gravelly or very gravelly sandy loam, and contains 15 to 40 percent gravel. It is neutral or slightly alkaline.
The 2Bkqm horizon is indurated throughout. It is moderately alkaline.
The 3C horizon is extremely gravelly or very gravelly sand or coarse sand and contains 35 to 70 percent gravel.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Tumalo soils are on nearly level outwash plains at 3,000 to 4,000 feet elevation. Slopes are 0 to 8 percent. The soils formed in volcanic ash over glacial outwash. The climate is characterized by cool, moist winters and hot, dry summers. The mean annual precipitation is 10 to 12 inches. The mean annual temperature is 47 to 52 degrees F. The frost-free period is 70 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Clinefalls and the Plainview soils. They are on outwash plains and lack a duripan above 40 inches.
DRAINAGE AND PERMEABILITY: Well drained; moderately rapid to the duripan and very slow through it.
USE AND VEGETATION: These soils are used for irrigated crops, pasture, and livestock grazing. Potential native vegetation is western juniper, antelope bitterbrush, mountain big sagebrush, antelope bitterbrush, Idaho fescue, and needleandthread.
DISTRIBUTION AND EXTENT: Deschutes Basin of central Oregon; MLRA 10. The series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Deschutes County (Upper Deschutes River Area), Oregon, 1992.
REMARKS: The series was reclassified in 1992 from coarse-loamy, mixed, mesic Durixerollic Camborthids to ashy, mesic Duric Vitritorrands based on andic soil properties analysis.
mollic epipedon - from the soil surface to 10 inches (A1 and A2 horizons). The organic matter content is less then 1 percent in the AB horizon.
cambic horizon - from 18 to 32 inches (Bw horizon)
indurated duripan - from 32 to 44 inches.
andic soil properties - the zone from 0 to 32 inches has a phosphate retention of 58 percent, acid oxalate extractable aluminum plus one-half the acid oxalate iron of 0.47, 0.38, and 0.57 for the A2, AB, and Bw horizons, glass and glass-coated aggregate of 76, 66, and 62 percent for the same horizons and 15-bar water content of 7.0 on both moist and dry samples.
ADDITIONAL DATA: Laboratory data from the series type location, S86OR-017-006.