LOCATION IMBLER OREstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Pachic Haploxerolls
TYPICAL PEDON: Imbler fine sandy loam, cultivated. (Colors are for moist soil unless otherwise noted.)
Ap--0 to 7 inches; very dark brown (10YR 2/2) fine sandy loam, dark gray (10YR 4/1) dry; weak medium granular structure; soft, very friable; many very fine roots; many very fine and fine irregular pores; neutral (pH 6.6); abrupt smooth boundary. (5 to 7 inches thick)
A12--7 to 14 inches; very dark grayish brown (10YR 3/2) fine sandy loam, dark gray (10YR 4/1) dry; weak coarse prismatic structure parting to weak medium subangular blocky; soft, very friable; many very fine roots; many very fine and fine irregular pores; neutral (pH 6.8); clear smooth boundary. (6 to 10 inches thick)
AC--14 to 30 inches; dark brown (10YR 3/3) fine sandy loam, dark brown (10YR 4/3) dry; weak coarse prismatic and weak medium subangular blocky structure; soft, very friable; many very fine roots; many very fine and fine irregular pores; neutral (pH 6.8); diffuse wavy boundary. (15 to 20 inches thick)
C--30 to 100 inches; dark brown (10YR 4/3) loamy fine sand, brown (10YR 5/30 dry; single grained; loose; common very fine root to 72 inches and few roots below; many very fine irregular pores; neutral (pH 7.0).
TYPE LOCATION: Union County, Oregon; about 1,280 feet north and 1,400 feet east of SW section corner SE1/4 SW1/4 section 20, T.1S., R.38E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 47 to 53 degrees F. The mean summer soil temperature at a depth of 20 inches is 63 to 68 degrees F. These soils are usually moist, but are dry for 60 to 80 consecutive days in all parts between depths of 8 to 24 inches following the summer solstice. Depth to contrasting textures is more than 40 inches. The mollic epipedon is 20 to 36 inches thick. The soil has less than 30 percent medium and coarser sand in the particle size control section.
The A horizon has value of 2 or 3 moist, 3 or 4 dry and chroma of 1 or 2 moist and dry.
The AC horizon has chroma of 2 or 3 moist and dry. It is fine sandy loam or sandy loam. In some pedons, this is a B horizon.
The C horizon has value of 3 or 4 moist and chroma of 2 or 3 moist. It is loamy fine sand or fine sandy loam.
COMPETING SERIES: These are the Central Point, Edmundston, Oak Glen, Ritter, Stevens and Uhlig series. Central Point soils have a mean annual soil temperature of 52 to 56 degrees F., have a hard or very hard B horizon and have more than 30 percent medium and coarser sand in the particle size control section. Edmundston soils have a paralithic contact at a depth of 40 to 60 inches, have mean annual soil temperature at 52 to 59 degrees F., and are dry from about June to November. Oak Glen soils commonly are gravelly, slightly acid or medium acid, and have a mean annual soil temperature of about 54 to 59 degrees F. Ritter soils dominantly are loam in the 10 to 40 inch control section and are mildly alkaline in the lower part of the B horizon. Stevens soils are gravelly and hard in the lower part of the control section, are mildly alkaline or moderately alkaline and are calcareous at a depth of 25 to 40 inches. Uhlig soils have a silt loam or loam A horizon and a loam B horizon with the upper part loess and ash.
GEOGRAPHIC SETTING: Imbler soils are on undulating valley terraces at elevations of 2,600 to 2,800 feet and have slopes of 1 to 5 percent. The soils formed in eolian material weathered mainly from basalt and andesite. The climate is subhumid with warm dry summers and cool moist winters. The mean annual precipitation is 16 to 24 inches. The mean annual temperature is 47 to 51 degrees F. The average January temperature is 31 degrees F. The average summer temperature is 65 to 69 degrees F. The frost free period is 120 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Alicel and Palouse soils. Alicel soils are fine, loamy. Palouse soils are fine, silty.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderately rapid permeability.
USE AND VEGETATION: Imbler soils are used primarily for small grains, alfalfa, green peas, and grass seed production under dryland farming and irrigation. Native vegetation dominantly is threadleaf sedge, giant wildrye and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: Grande Ronde Valley of eastern Oregon. Series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Union County, Oregon, 1978.