Established Series


The Warrenton series consists of deep, very poorly drained soils that formed in sand. Warrenton soils are on long narrow interdunal areas and have slopes of 0 to 3 percent. The mean annual precipitation is about 85 inches. The mean annual temperature is about 50 degrees F.

TAXONOMIC CLASS: Sandy, mixed, isomesic Typic Humaquepts

TYPICAL PEDON: Warrenton loamy fine sand, brush and trees. (Colors are for moist soils unless otherwise noted.)

0--3 inches to 0; black (N 2/) muck, twigs, roots, needles, leaves, etc.

A--0 to 11 inches; black (N 2/) loamy fine sand; many fine and medium prominent dark reddish brown (5YR 3/4) and reddish brown (5YR 4/4) mottles and softly cemented lining along root channels; massive; friable, nonsticky and nonplastic; common fine roots; many very fine pores; strongly acid (pH 5.2); abrupt smooth boundary. (10 to 15 inches thick)

Cg1--11 to 22 inches; very dark gray (2.5Y 3/) loamy fine sand; many fine, medium and large prominent dark reddish brown (5YR 3/4), reddish brown (5YR 4/4) and yellowish red (5YR 4/6) mottles and splotches; massive; friable, nonsticky and nonplastic; few fine roots; many very fine pores; strongly acid (pH 4.8); abrupt smooth boundary. (10 to 25 inches thick)

Cg2--22 to 60 inches; very dark gray (2.5Y 3/) fine sand; few fine and medium prominent reddish brown (5YR 3/4) mottles; single grained; very strongly acid (pH 4.8).

TYPE LOCATION: Clatsop County, Oregon; 100 yards up private driveway along the second swale east of U.S. Highway 101 on Dellmoor Road; SE1/4 SW1/4 section 27, T.7N., R.10W.

RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 49 to 53 degrees F. The difference between the mean winter and mean summer soil temperature is 5 to 9 degrees F. The soil is always moist and is saturated for about 6 to 8 months. The umbric epipedon is 10 to 15 inches thick. The particle size control section has 5 to 10 percent clay and 80 percent or more sand coarser than very fine sand.

The A horizon has hue of 10YR through 5Y, value of 2, chroma of 0 through 2. It has 4 to 10 organic matter. It is massive or very weak subangular blocky structure. In the natural state, the A horizon is overlain by 1 to 4 inches of an 0 horizon. It is strongly or very strongly acid.

The Cg horizon has hue of 5Y through 10YR, value of 3 or 4 and chroma of neutral through 2. Prominent mottles have hue of 5 YR or 7.5YR, value of 3 or 4, and chroma of 4 through 6. It is loamy fine sand or fine sand. It is massive or single grained. It is extremely or very strongly acid.

COMPETING SERIES: There are no other soils in this family. The Heceta series has an ochric epipedon.

GEOGRAPHIC SETTING: The Warrenton soils are primarily in long narrow interdunal areas but may also be on broad level areas between dunes. They have formed in sand and are at elevations of 10 to 20 feet. The climate has a warm moist summer and a warm wet winter. Many summer days have fog or low cloud cover during the mornings. The mean annual precipitation is 70 to 100 inches. The mean July temperature is 59 degrees F.; the mean January temperature is 38 degrees F.; and the mean annual temperature is 50 degrees F. The frost free season is 175 to 260 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Brallier, Coquille, Depoe, Gearhart, Netarts, Waldport and Yaquina series. The Brallier soils have organic material to over 60 inches. Coquille soils are in the fine, silty family. Depoe, Netarts and Yaquina soils have a spodic horizon. Gearhart soils are somewhat excessively drained and on dunes.

DRAINAGE AND PERMEABILITY: Very poorly drained; slow to ponded runoff; rapid permeability. The water table is 1 to 2 feet below the surface during the summer and up to 1 foot above the surface during the winter.

USE AND VEGETATION: Primarily permanent pasture with some blueberries and cranberries. Native vegetation consists of willow, red alder, sitka spruce, western red cedar, tussocks, skunk cabbage and sawgrass rush.

DISTRIBUTION AND EXTENT: Along the middle and north Oregon coast. The series is inextensive.


SERIES ESTABLISHED: Clatsop County, Oregon, 1938.

National Cooperative Soil Survey
U. S. A.