LOCATION AHL WAEstablished Series
TAXONOMIC CLASS: Medial-skeletal, mixed, mesic Typic Haploxerands
TYPICAL PEDON: Ahl very gravelly loam, forested. (Colors are for moist soil unless otherwise noted.)
O1--3 to 1 inches; needles, leaves, twigs, bark, moss, wood fragments.
O2--1 inch to 0; decomposing organic litter.
B21ir--0 to 3 inches; dark reddish brown (5YR 3/4) very gravelly loam, reddish brown (2.5YR 5/4) dry; weak fine and very fine granular structure; soft, very friable, slightly sticky, plastic; smeary; many fine, medium, and large roots; 55 percent angular basalt gravel; moderately acid (pH 5.8); clear wavy boundary. (2 to 6 inches thick)
B22ir--3 to 20 inches; dark red (2.5YR 3/6) very gravelly loam, reddish brown (2.5YR 5/4) dry; weak fine granular and subangular blocky structure; soft, very friable, slightly sticky, plastic; smeary; many fine, medium, and large roots; 55 percent angular basalt and 5 percent rounded gravel; moderately acid (pH 6.0); gradual wavy boundary. (10 to 18 inches thick)
B3--20 to 30 inches; reddish brown (5YR 4/4) very gravelly loam, light reddish brown (5YR 6/4) dry; massive; soft, friable, nonsticky, nonplastic; smeary; common fine roots; 70 percent angular basalt gravel; slightly acid (pH 6.4); gradual wavy boundary. (10 to 18 inches thick)
C--30 to 38 inches; 90 percent fractured basalt bedrock. Material in voids is reddish brown (5YR 4/4) very gravelly loam, light reddish brown (5YR 6/4) dry; massive; slightly acid (pH 6.4); gradual wavy boundary. (4 to 12 inches thick)
R--38 inches; basalt bedrock.
TYPE LOCATION: Jefferson County, Washington; 1.2 miles south of U. S. Highway 101, along the Mt. Walker Road, and 15 feet east of road; SE1/4 NW1/4 SE1/4 sec. 34, T.27N., R.2W.
RANGE IN CHARACTERISTICS: The mean annual soil temperature at 20 inches is 47 degrees to about 50 degrees F. These soils are usually moist and are not dry in all parts between 8 and 24 inches for as much as 60 consecutive days or in some part for as much as 90 cumulative days. The soils are moderately acid to slightly acid. The solum is 20 to 36 inches thick. Depth to consolidated basalt bedrock is 24 to 40 inches. Content of coarse fragments in the control section is 50 to 90 percent. The Bir horizon has hue of 2.5YR or 5YR, value of 2 through 4 moist, and chroma of 2 through 4 moist. The B3 horizon has hue of 2.5YR or 5YR, value and chroma of 4 through 6 moist. It is gravelly loam or very gravelly loam. The C horizon contains more than 80 percent fractured basalt bedrock, with voids filled with material similar to that of the B3 horizons.
COMPETING SERIES: These are the Alderwood, Beausite, Cathcart, Dabob, Everett, Hoodsport, Klaus, Olete, Sinclair, Stetson, and Whidbey series. Alderwood, Dabob, Hoodsport, Sinclair, and Whidbey soils have paralithic or lithic contacts within 40 inches. Beausite soils have gravelly sandy loam or very gravelly sandy loam control sections. Cathcart soils have 18 to 35 percent clay in the control section and contain less than 50 percent coarse fragments in some part of the control section. Everett soils have 10YR or 7.5YR hue in the B horizon. Klaus soils have coarse apparent field textures. Olete soils have solums thinner than 20 inches.
GEOGRAPHIC SETTING: Ahl soils occur on steep to very steep mountainous topography at elevations of 800 to about 3,000 feet. These soils formed in colluvial material from basalt. They occur in a mild, cool marine climate having an annual precipitation of 50 to 100 inches, most of which falls as rain during the fall, winter, and spring months; mean annual temperature is about 49 degrees F.; the average summer temperature is about 60 degrees F.; the average winter temperature is about 36 degrees F.; and the frost-free period is 160 to 190 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Grove, and Triton soils and the competing Hoodsport soils. Grove soils have coarse-textured control sections. Triton soils have a strongly cemented pan at depths of 12 to 20 inches.
DRAINAGE AND PERMEABILITY: Well-drained; medium or rapid runoff; moderate permeability.
USE AND VEGETATION: Woodland and watershed. Dominant vegetation is Douglas-fir, western redcedar, vine maple, rhododendron, huckleberry, salal, and Oregon grape.
DISTRIBUTION AND EXTENT: Northwestern Washington. Series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Jefferson County, Washington, 1971.
REMARKS: This draft is a reformat only of a 1971 description. The classification is tentative. Soils in the area forming from basalt have failed to meet chemical criteria for spodisols. These soils are probably Andic Dystrochrepts or Entic Dystrandepts. The soils at elevations above about 1,800 feet probably have a "frigid" temperature regime.
Classification only changed 4/94 because of recent amendments to Soil Taxonomy. The range of this soil appears to be both in the Xeric and Udic soil moisture regimes (3/24/94).