LOCATION LOGDELL OREstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Lithic Ultic Haploxerolls
TYPICAL PEDON: Logdell extremely channery ashy loam - rangeland, on a 68 percent slope at an elevation of 3,800 feet. (Colors are for moist soil unless otherwise noted. When described on June 27, 1974, the soil was dry throughout.)
A--0 to 8 inches; very dark brown (10YR 2/2) extremely channery ashy loam, very dark grayish brown (10YR 3/2) dry; weak fine granular structure; soft, friable, slightly sticky and slightly plastic; many very fine, few fine and medium roots; many very fine pores; 50 percent angular shale channers and 10 percent flagstones; neutral (pH 6.6); clear wavy boundary. (4 to 12 inches thick)
R--8 inches; dark gray (N 4/) highly fractured shale.
TYPE LOCATION: Grant County, Oregon; about 5 miles southwest of the town of Mt. Vernon; SW1/4 SW1/4 section 12, T. 14 S., R. 29 E. (Latitude 44 degrees, 21 minutes, and 58 seconds N. and Longitude 119 degrees, 11 minutes, and 29 seconds W.)
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 42 to 47 degrees F. These soils are usually moist but are dry in the control section for 60 to 80 consecutive days during the four-month period following the summer solstice. The solum is slightly acid or neutral. Depth to fractured shale ranges from 4 to 12 inches. The solum has glass content of 10 to 30 percent. Acid oxalate extractable aluminum plus one-half the iron is 0.3 to 0.7 percent.
The A horizon has 10YR hue but ranges to 7.5YR. It has value of 2 or 3 moist, 3 or 4 dry and chroma of 2 or 3. It is ashy loam with 18 to 27 percent clay. It has 35 to 70 percent shale fragments with 0 to 10 percent flagstones and 35 to 60 percent channers. Base saturation by sum is 65 to 75 percent.
The R horizon is fractured shale. Some fines are in fractures and voids in upper few inches only.
COMPETING SERIES: This is the Laycock series. Laycock soils are deeper than 12 inches to bedrock.
GEOGRAPHIC SETTING: Logdell soils are on hillsides. Elevations are 3,500 to 5,500 feet on north slopes but can range up to 6,600 feet on south slopes. Slopes are 15 to 75 percent. They were dominantly formed in shaly colluvium and residuum weathered from finely fractured shale interbedded in places with sandstone and graywacke. Less common are Logdell soils formed in highly fractured, flaggy and channery rhyolite. The climate is characterized by cold, wet winters and hot, dry summers. The mean annual precipitation is 17 to 22 inches. The mean annual temperature is 40 to 45 degrees F., the mean July temperature is about 63 degrees F., and the mean January temperature is about 25 degrees F. The frost-free period is 30 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hankins, McGarr, Piersonte and Tolo soils and the competing Laycock soils. Hankins soils have a clayey argillic horizon. McGarr soils are fine-loamy and 20 to 40 inches deep to a lithic contact. Piersonte soils are deep. Tolo soils are deep and are ashy over loamy.
DRAINAGE AND PERMEABILITY: Well-drained; slow to rapid runoff; moderate permeability.
USE AND VEGETATION: Livestock grazing and wildlife habitat. The native vegetation is mainly mountain-mahogany, snowbrush, Idaho fescue and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: Principally in southern Grant County, Oregon. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Grant County, Oregon, 1975.
REMARKS: Diagnostic horizons and features in this pedon include:
Mollic epipedon - from 0 to 8 inches (A horizon).
Lithic contact - 8 inches (R).
ADDITIONAL DATA: s97or-023-024.