LOCATION MARKSCREEK ORTentative Series
TAXONOMIC CLASS: Coarse-loamy over sandy or sandy-skeletal, mixed, superactive, frigid Cumulic Haploxerolls
TYPICAL PEDON: Markscreek loam, on a 2 percent slope, pasture. (Colors are for moist soil unless otherwise noted.)
A1--0 to 9 inches; very dark brown (10YR 2/2) loam, dark gray (10YR 4/1) dry; weak thin platy structure parting to weak fine granular; soft, friable, slightly sticky and slightly plastic; many very fine and fine roots; many fine interstitial pores; neutral (pH 6.6); clear smooth boundary.
A2--9 to 16 inches; very dark grayish brown (10YR 3/2) loam, grayish brown (10YR 5/2) dry; weak very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; many fine interstitial pores; neutral (pH 6.8); clear wavy boundary. (Combined thickness of the A horizon is 10 to 25 inches)
AC--16 to 24 inches; very dark grayish brown (10YR 3/2) loam, grayish brown (10YR 5/2) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; common fine tubular pores; neutral (pH 7.0); abrupt smooth boundary. (5 to 15 inches thick)
2C--24 to 60 inches; very dark grayish brown (10YR 3/2) very gravelly sand, grayish brown (10YR 5/2) dry; single grain; loose, nonsticky and nonplastic; few very fine and fine roots; 40 percent gravel and 10 percent cobbles; neutral (pH 7.0).
TYPE LOCATION: Crook County, Oregon; 2,000 feet east and 300 feet north of the SW corner of section 13, T.14 S, R.18 E.
RANGE IN CHARACTERISTICS: These soils are usually moist but are dry in the moisture control section for 80 to 100 days following the summer solstice. The mean annual soil temperature ranges from 42 to 47 degrees F. Depth to bedrock is greater than 60 inches. Depth to the 2C horizon is 20 to 40 inches. The mollic epipedon ranges from 20 to 40 inches thick. The weighted average clay content in the upper part of the particle-size control section is 10 to 18 percent.
The A1 horizon has value of 2 or 3 moist, 3 or 4 dry, and chroma of 1 or 2 moist and dry. It contains 0 to 30 percent gravel.
The A2 and AC horizons have value of 2 or 3 moist, 4 or 5 dry, and chroma of 2 or 3 moist and dry. It is loam, silt loam and very fine sandy loam and contains 0 to 15 percent gravel.
The 2C horizon has value of 2 or 3 moist, 4 or 5 dry, and chroma of 2 or 3 moist and dry. It is loamy sand or sand and contains 20 to 40 percent gravel and 10 to 35 percent cobbles.
COMPETING SERIES: Theses are the Boesel and Josset series. Boesel soils are dry for 60 to 75 consecutive days, have 14 to 18 inches of precipitation , are moderately well drained and are derived from glacial outwash. Josset soils are calcareous throughout, slightly to moderately alkaline, and they are moderately well drained with a water table at 30 to 40 inches from January to June.
GEOGRAPHIC SETTING: Markscreek soils are on low terraces at elevations of 3,600 to 4,000 feet. Slopes range from 0 to 3 percent. These soils formed in mixed alluvium. The climate is characterized by cold, wet winters and hot, dry summers. The mean annual precipitation is 12 to 16 inches, the mean annual temperature is 40 to 44 degrees F, and the frost-free period is 70 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These include Gerow, Hankins, Luckybutte, and Yawkey soils. Gerow soils are fine-loamy and somewhat poorly drained. Hankins soils are fine and are on adjacent south-facing sideslopes. Luckybutte soils are on floodplains, are fine-loamy over sandy or sandy-skeletal and are very poorly drained. Yawkey soils are clayey-skeletal and are on adjacent south-facing sideslopes.
DRAINAGE AND PERMEABILITY: Well drained; permeability is moderate over very rapid.
USE AND VEGETATION: This soil is used mainly for pasture. Native vegetation is basin wildrye, and basin big sagebrush.
DISTRIBUTION AND EXTENT: Central Oregon. This series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Crook County, Oregon, 2000.
REMARKS:
Mollic epipedon - the zone from the surface to a depth of 24
Cumulic feature - a mollic epipedon that is 24 inches thick and an irregular decrease in organic carbon with increasing depth based on the nature of the parent material.
Contrasting particle-size- occurring at 24 inches.
This pedon was the type location for the Veazie soil in the Prineville Area, Oregon Soil Survey, issued 2/66. The area mapped as Veazie in the Prineville survey is now considered to be frigid. The Veazie type location is moved to Union County, Oregon.