LOCATION AVERLANDE OREstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic, mesic Lithic Hapludults
TYPICAL PEDON: Averlande gravelly loam, woodland. On a 5 percent southwest-facing slope at an elevation of 1,960 feet. (When described on May 10, 1985, the soil was moist throughout. Colors are for moist soil unless otherwise noted.)
Oi--0 to 1 inch; partially decomposed needles, leaves, twigs, and woody materials.
A--1 to 4 inches; dark brown (7.5YR 4/4) gravelly loam, light brown (7.5YR 6/4) dry; moderate very fine subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; many fine and very fine roots; many fine irregular pores; 25 percent gravel; very strongly acid (pH 4.8); clear smooth boundary. (2 to 4 inches thick)
BAt--4 to 8 inches; yellowish red (5YR 5/6) gravelly loam, reddish yellow (7.5YR 6/6) dry; moderate very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and very fine roots; many very fine continuous tubular pores; few faint clay films on ped faces and in pores; 25 percent gravel; very strongly acid (pH 4.8); clear smooth boundary. (0 to 8 inches thick)
Bt--8 to 15 inches; red (2.5YR 5/6) very gravelly clay loam, reddish yellow (5YR 6/6) dry; moderate very fine subangular blocky structure; slightly hard, friable, sticky and plastic; common fine and very fine roots; many very fine continuous tubular pores; common distinct clay films on ped faces and in pores; 50 percent gravel and 10 percent cobbles; very strongly acid (pH 4.6); gradual wavy boundary. (7 to 9 inches thick)
R--15 inches; partially weathered metavolcanic rock.
TYPE LOCATION: Curry County, Oregon; located about 2,250 feet north and 1,600 feet west of the southeast corner of section 10, T. 40 S., R. 13 W.; W.M.(Latitude 42 degrees, 07 minutes, 35 seconds N; Longitude 124 degrees, 13 minutes, 34 seconds W.)
RANGE IN CHARACTERISTICS: The soils are usually moist and are dry less than 45 consecutive days between 4 and 12 inches in the four months following the summer solstice. The mean annual soil temperature is about 47 to 54 degrees F. The particle-size control section has 25 to 35 percent clay and 35 to 85 percent rock fragments. Depth to bedrock and solum thickness is 10 to 20 inches.
The A and BAt horizons have hue of 7.5YR or 5YR, value of 4 to 6 moist and dry and chroma of 4 to 6 moist and dry. It is gravelly loam with 15 to 25 percent clay. It has 15 to 25 percent gravel and 0 to 10 percent cobbles.
The Bt horizon has hue of 5YR or 2.5YR, value of 5 or 6 moist and dry and chroma of 4 to 6 moist and dry. It is very gravelly clay loam, extremely gravelly clay loam, or very gravelly silty clay loam with 27 to 35 percent clay. It has 35 to 70 percent gravel and 0 to 15 percent cobbles.
COMPETING SERIES: This is the Taumsauk series. Taumsauk soils have a mean annual soil temperature greater than 54 degrees F.
GEOGRAPHIC SETTING: Averlande soils are on stable to metastable ridgetops and stable benches of mountains. The soils formed in colluvium and residuum from metasedimentary or metavolcanic rock types of the Dothan Formation. Slopes are 0 to 30 percent. Elevations are 400 to 3,000 feet. The climate is characterized by warm wet winters and hot moist summers. The mean annual precipitation is 90 to 130 inches. The mean annual temperature is 45 to 53 degrees F. The frost-free period is 120 to 210 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bravo, Cassiday, Colepoint, Crutchfield, Fritsland, Grouslous, Hazelcamp, and Skookumhouse soils. All of these soils occur on broad ridgetops, benches, or side slopes of mountains. Bravo, Cassiday, Crutchfield, and Hazelcamp soils are 20 to 40 inches deep to bedrock. Colepoint, Fritsland, and Skookumhouse soils are 40 to 60 inches deep to bedrock. Grouslous soils lack an argillic horizon.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: These soils are used mainly for woodland, wildlife habitat, watershed, and recreation. Vegetation is Douglas fir, tanoak, Pacific madrone, canyon live oak, salal, hairy manzanita, evergreen huckleberry, Pacific rhododendron, cascade Oregongrape, western brackenfern, western hazel, western swordfern, and common beargrass.
DISTRIBUTION AND EXTENT: Mountainous areas of southwestern Oregon; MLRA 1. The series is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Curry County, Oregon, 1995. The name is coined.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Argillic horizon - from 8 to 15 inches (Bt horizon)
Particle-size control section - from 8 to 15 inches (Bt horizon) with 43 percent rock fragments and 28 percent clay calculated as a weighted average.
All diagnostic horizons and features are measured from the to of the first mineral horizon.