These soils formed in material weathered from siltstone and very fine grained sandstone. Elevation ranges from near sea level to 1,100 feet. They occur in a coastal marine climate with cool, wet winters and cool, dry summers. The annual precipitation ranges from 80 to 120 inches. These are the competing Ilwaco , Knappton , Lebam , Narel , Swem , Vesta , and Willapa soils.
Principal uses are timber production, watershed, wildlife habitat, and recreation.
The major tree species are western hemlock and Douglas fir, with scattered Sitka spruce, western red cedar, and red alder. Understory species are salal, oxalis, swordfern, brachenfern, salmonberry, blackberry, red elderberry, and vine maple. Within 20 miles of the Pacific Ocean in southwestern Washington and possibly northwestern Oregon. The series is moderately extensive. Pacific County, Washington, 1978.