LOCATION CAMPFOUR OR

Established Series
Rev. DRJ/TDT
01/2023

CAMPFOUR SERIES

The Campfour series consists of deep, well drained soils that formed in residuum and colluvium weathered from andesite or basalt. Campfour soils are on plateaus and hillslopes and have slopes of 1 to 35 percent. The mean annual temperature is about 48 degrees F, and the mean anuual precipitation is about 23 inches.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Pachic Ultic Argixerolls

TYPICAL PEDON: Campfour loam, forested. (Colors are for moist soil unless otherwise noted.)

O--1 inch to 0; partially decomposed needles and twigs.

A--0 to 5 inches; dark reddish brown (5YR 3/2) loam, reddish brown (5YR 4/3) dry; strong very fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and common fine, medium, and coarse roots; many very fine irregular pores; 9 percent gravel and 5 percent cobbles; moderately acid (pH 5.8); clear smooth boundary. (2 to 12 inches thick)

AB--5 to 21 inches; dark reddish brown (5YR 3/3) loam, reddish brown (5YR 4/4) dry; moderate very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and common fine, medium, and coarse roots; many very fine tubular pores; 9 percent gravel and 5 percent cobbles; moderately acid (pH 5.6); clear wavy boundary. (0 to 16 inches thick)

Bt1--21 to 50 inches; dark reddish brown (5YR 3/3) clay loam, reddish brown (5YR 4/4) dry; moderate very fine and fine angular blocky structure; hard, firm, sticky and plastic; common very fine and few fine, medium, and coarse roots; common very fine tubular pores; common thin clay films on ped faces and in pores; 10 percent gravel; moderately acid (pH 5.6); gradual wavy boundary. (10 to 30 inches thick)

Bt2--50 to 60 inches; dark reddish brown (5YR 3/4) gravelly clay loam, reddish brown (5YR 4/4) dry; moderate very fine and fine angular blocky structure; hard, firm, sticky and plastic; few very fine, fine, and medium roots; common very fine tubular pores; common thin clay films on ped faces and in pores; 15 percent gravel; moderately acid (pH 5.6).

TYPE LOCATION: Klamath County, Oregon; approximately 800 feet south and 1,500 feet east of the northwest corner of sec. 1, T. 41 S., R. 5 E., W.M.

RANGE IN CHARACTERISTICS: These soils are usually moist but are dry in the moisture control section for 80 to 100 consecutive days in the four months that follow the summer solstice. The
mean annual soil temperature is 47 to 52 degrees F. The mollic epipedon is 20 to 40 inches thick and includes the upper part of the argillic horizon. Depth to bedrock is greater than 60 inches. The soil has a base saturation of 60 to 90 percent in the A and AB horizons and 50 to 75 percent throughout the Bt horizon. The particle-size control section averages 27 to 35 percent clay, 5 to 30 percent gravel, and 0 to 10 percent cobbles.

The A horizon has hue of 7.5YR, 5YR or 2.5YR, moist and dry,
value of 2 or 3 moist, and chroma of 2 or 3 moist, and 3 or 4
dry. It has 0 to 15 percent gravel and 0 to 5 percent cobbles.
It is moderately acid to slightly acid.

The Bt horizon has hue of 5YR or 2.5YR moist and 7.5YR through
2.5YR dry, and chroma of 3 or 4 moist and dry. It has 27 to 35 percent clay, 5 to 30 percent gravel, and 0 to 10 percent
cobbles. It is clay loam, gravelly clay loam, or cobbly clay
loam. It is strongly acid to slightly acid.

COMPETING SERIES: These are the Aptos, Elmore, Nisene, and Paragon series. Aptos and Paragon soils are 20 to 40 inches to a paralithic contact. Elmore soils lack an O horizon are dry for 45 to 70 consecutive days and have hue of 10YR and 7.5YR in the Bt. Nisene soils have a mean annual soil temperature of 56 to 58 degrees F and have hue of 10YR or 7.5YR in the Bt.

GEOGRAPHIC SETTING: Campfour soils are on plateaus and hillslopes at elevations of 3,000 to 4,400 feet. These soils formed in residuum and colluvium derived from basalt and andesite with small amounts of volcanic ash in the upper part. The mean annual precipitation is 20 to 25 inches. The mean annual temperature is 45 to 51 degrees F. The frost-free period is 100 to 130 days. Slopes range from 1 to 35 percent.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the McMullin, Paragon, Randcore, Shoat, and Skookum soils. McMullin and Randcore soils are less than 20 inches to bedrock. Paragon and
Shoat soils have bedrock at depths of 20 to 40 inches. Skookum soils are clayey-skeletal.

DRAINAGE AND PERMEABILITY: Well drained; slow to moderate runoff; moderately slow permeability.

USE AND VEGETATION: These soils are used for timber production and livestock grazing. Native vegetation includes an overstory of ponderosa pine and Douglas fir. Also included in varying
amounts are incense cedar, sugar pine, California black oak, and Oregon white oak. Understory includes western fescue, tall Oregon grape, snowberry, prostrate ceanothus, and Pacific serviceberry.

DISTRIBUTION AND EXTENT: Southwestern Oregon. The series is inextensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES ESTABLISHED: Jackson County Area, Oregon (Klamath County part), 1988.

REMARKS: Diagnostic horizons and features:

- Mollic epipedon - 0 to 30; assume organic carbon is less than
0.6 percent from 30 to 50 inches and color is derived from parent material.

- Assume base saturation of greater than 50 percent throughout profile and less than 75 percent throughout argillic horizon.

- Argillic horizon - 21 to 60 inches.

The superactive cation exchange activity class was added in 03/2003 to the taxonomic classification by the National Soil Survey Center on request of the Reno MLRA office, without review of the soil series property data. The remainder of this document has not been updated.

ADDITIONAL DATA: Pedon was sampled for; organic carbon, base saturation, particle-size and mineralogy. Sample depths; 0-5, 5-21, 21-30, 30-50 inches.

National Cooperative Soil Survey
U.S.A.