LOCATION HESSLAN OR
Established Series
Rev. DFA/GLG/AON
01/2023
HESSLAN SERIES
The Hesslan series consists of moderately deep, well drained soils that formed in loess, ash and colluvium weathered from sedimentary bedrock. These soils are on uplands and have slopes of 5 to 70 percent. The mean annual precipitation is about 17 inches and the mean annual air temperature is about 47 degrees F.
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Typic Haploxerolls
TYPICAL PEDON: Hesslan stony loam, rangeland. (Colors are for moist soil unless otherwise noted.)
A1--0 to 3 inches; very dark grayish brown (10YR 3/2) stony loam, grayish brown (10YR 5/2) dry; weak medium platy structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine tubular pores; 5 percent gravel, 5 percent cobbles and 5 percent stones; neutral (pH 6.6); abrupt smooth boundary. (2 to 6 inches thick)
A2--3 to 9 inches; very dark grayish brown (10YR 3/2) stony loam, grayish brown (10YR 5/2) dry; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine tubular pores; 5 percent gravel, 5 percent cobbles, and 5 percent stones; neutral (pH 6.6); abrupt smooth boundary. (5 to 9 inches thick)
Bw1--9 to 18 inches; dark brown (10YR 3/3) loam, brown (10YR 5/3) dry; weak medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine tubular pores; 5 percent gravel and 5 percent cobbles; neutral (pH 6.6); clear smooth boundary. (0 to 12 inches thick)
Bw2--18 to 23 inches; brown (10YR 4/3) cobbly loam, pale brown (10YR 6/3) dry; weak medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine tubular pores; 10 percent gravel and 10 percent cobbles; neutral (pH 6.6); abrupt wavy boundary. (4 to 15 inches thick)
2Cr--23 to 30 inches; brown (10YR 5/3) semiconsolidated sandstone; extremely hard.
TYPE LOCATION: Wasco County, Oregon; about 500 feet north of county road in the NW1/4 SW1/4 SE1/4 section 1, T.1S., R.12E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 47 to 51 degrees F. The soil are usually moist, but are dry each year for 60 to 80 consecutive days between depths of 8 and 24 inches within the 4 month period following the summer solstice. Thickness of the solum and depth to paralithic contact range from 20 to 40 inches. Rock fragments range from 5 to 20 percent in the A horizons and 5 to 30 percent in the B horizons. Surface stones range from 5 to 20 percent. The mollic epipedon is 7 to 15 inches thick.
The A horizon has value of 4 or 5 dry, 2 or 3 moist and chroma of 2 or 3 moist and dry. It is stony loam or cobbly loam.
The B horizon has value of 5 or 6 dry, 3 or 4 moist, and chroma of 2 or 3 moist and dry. It is loam or cobbly loam with 10 to 18 percent clay and more than 15 percent coarser than very fine sand. This horizon has weak or moderate medium or fine subangular blocky structure.
COMPETING SERIES: These are the
Anders,
Battleplain,
Chenoweth,
Cleverly,
Conconully,
Duart, Juliaetta,
Knutsen,
Laidlaw,
Newbon,
Owhi,
Phoebe,
Uhlig, and
Wato series. Anders soils have a lithic contact at depths of 20 to 40 inches. Battleplain, Chenoweth, Cleverly, Conconully, Juliaetta, Knutsen, Laidlaw, Newbon, Owhi, Phoebe, Uhlig and Wato soils lack a paralithic or lithic contact above depth of 40 inches. Also, Battleplain, Jnutsen, Laidlaw and Phoebe soils are moderately coarse textured. Durart soils dominantly are silt loam, have less than 5 percent rock fragments and are dry for 80 to 90 days.
GEOGRAPHIC SETTING: Hesslan soils are on south-facing slopes at elevations of 500 to 3,500 feet. Slopes are 5 to 70 percent. These soils formed in colluvium weathered from sedimentary bedrock mixed with loess and volcanic ash. The climate is semiarid with a mean annual precipitation of 14 to 20 inches. The mean annual temperature is about 45 to 49 degrees F.; the mean winter temperature is about 37 degrees F.; and the mean summer temperature is about 60 degrees F. The frost-free season is 100 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Chenoweth,
Cherryhill,
Frailey,
Skyline, and
Wamic soils. Chenoweth and Cherryhill soils have less steep slopes, are fine, loamy, and are deeper than 40 inches to bedrock. Frailey soils are 40 to 60 inches deep to bedrock. Skyline soils are less than 20 inches deep to semiconsolidated sandstone. Wamic soils commonly have less steep slopes, lack mollic epipedons and rock fragments, and have very hard or extremely hard 2C horizons at depths of 24 to 36 inches.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; moderate permeability.
USE AND VEGETATION: Range. Present vegetation is cheatgrass, bluebunch wheatgrass, balsamroot, bitterbrush, oak, and pine.
DISTRIBUTION AND EXTENT: Uplands of north central Oregon. The series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Wasco County, Oregon, 1975.
REMARKS: Diagnostic horizons and other features:
Mollic epipedon from 0 to 18 inches
Cambic horizon from 9 to 23 inches
National Cooperative Soil Survey
U.S.A.