LOCATION HONEYGROVE OREstablished Series
TAXONOMIC CLASS: Fine, mixed, active, mesic Typic Palehumults
TYPICAL PEDON: Honeygrove paragravelly silty clay loam, woodland, on a 15 percent south facing slope at an elevation of 1,270 feet. (Colors are for moist soil unless otherwise noted. When described on July 10, 2001 the soil was moist throughout.)
Oi--0 to 2 inches; slightly decomposed plant material; abrupt smooth boundary.
A--2 to 6 inches; dark brown (7.5YR 3/3) paragravelly silty clay loam, brown (7.5YR 4/3) dry; weak fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine and fine irregular pores; few faint discontinuous clay films along surfaces of pores and few faint patchy clay films in root channels; common fine black (7.5YR 2.5/1) iron-manganese nodules, spherical in matrix, moderately cemented; 5 percent gravel; 25 percent paragravel; strongly acid (pH 5.2); NaF (pH>9.5); abrupt smooth boundary. (4 to 8 inches thick)
BAt--6 to 17 inches; dark brown (7.5YR 3/4) silty clay loam, brown (7.5YR 4/4) dry; moderate fine and medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; common fine and medium, and few very fine and coarse roots; common fine and medium, and few very fine and coarse tubular pores; common faint clay films on ped faces, along surface of pores, and in root channels; common fine black (7.5YR 2.5/1) iron-manganese nodules, spherical in the matrix, moderately cemented; 2 percent gravel; 10 percent paragravel; very strongly acid (pH 5.0); NaF (pH>9.5); clear smooth boundary. (0 to 12 inches thick)
Bt1--17 to 31 inches; dark reddish brown (5YR 3/4) silty clay, reddish brown (5YR 4/4) dry; moderate fine and medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common fine, and few medium and coarse roots; few fine and medium tubular pores; common distinct clay films on ped faces, along surfaces of pores, and in root channels; common fine black (7.5YR 2.5/1) iron-manganese nodules, spherical in the matrix, moderately cemented; 2 percent gravel; 5 percent paragravel; very strongly acid (pH 4.8); NaF (pH>9.5); clear smooth boundary.
Bt2--31 to 43 inches; dark reddish brown (5YR 3/4) silty clay, reddish brown (5YR 4/4) dry; strong medium subangular blocky structure; hard, very firm, moderately sticky and moderately plastic; few fine and medium roots; few fine and medium tubular pores; common prominent clay films on ped faces, along surfaces of pores, and in root channels; 1 percent gravel; 2 percent paragravel; very strongly acid (pH 4.8); NaF (pH>9.5); gradual smooth boundary.
Bt3--43 to 56 inches; dark reddish brown (5YR 3/4) silty clay, yellowish red (5YR 4/6) dry; strong medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few fine, medium, coarse roots; few fine, medium, and coarse tubular pores; many prominent clay films on ped faces, along surfaces of pores, and in root channels; 5 percent paragravel; very strongly acid (pH 4.8); NaF (pH>9.5); gradual smooth boundary.
Bt4--56 to 75 inches; yellowish red (5YR 4/6) paragravelly silty clay, yellowish red (5YR 5/6) dry; moderate medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few medium tubular pores; many prominent clay films on ped faces, along surfaces of pores, and in root channels; 25 percent paragravel; very strongly acid (pH 4.8); NaF (pH>9.5); abrupt wavy boundary. (Combined Bt horizon is 40 to 90 inches thick)
Crt--75 to 85 inches; moderately cemented siltstone bedrock, fractured at intervals of 18 to less than 39 inches; many distinct clay films coat pararock fragments.
TYPE LOCATION: Benton County, Oregon; about 2,310 feet south and 1,320 feet east of the northwest corner of section 1, T. 12S., R. 7W. (Latitude 44 degrees, 33 minutes, 28 seconds N.; Longitude 123 degrees, 29 minutes, 24 seconds W.; Wren, OR 7.5 minute USGS Quad; NAD 1983)
RANGE IN CHARACTERISTICS: The mean annual soil temperature is typically 47 to 55 degrees F., and ranges to 57 degrees F. in the more southern reaches of the Cascade and Coast Ranges in Oregon. The soil is usually moist and is dry between depths of 4 and 12 inches for less than 45 consecutive days in the four-month period following the summer solstice in most years. The particle-size control section is 45 to 60 percent clay with 0 to 20 percent total rock fragments and 0 to 35 percent pararock fragments. The thickness of the solum and depth to bedrock is greater than 60 inches. Reaction is slightly acid to very strongly acid.
The A horizon has hue of 5YR or 7.5YR, value of 2 or 3 moist, 3 to 5 dry and chroma of 2 to 4 moist and dry. Texture is silty clay loam, paragravelly silty clay loam, clay loam, or gravelly clay loam averaging 27 to 40 percent clay. It has 0 to 30 percent gravel and 0 to 25 percent paragravel. The surface layer may have weakly smeary or moderately smeary consistence when the soil is derived from igneous parent materials.
The Bt horizon has hue of 2.5YR or 5YR, value of 3 to 5 moist, 4 to 7 dry, and chroma of 4 to 6 moist and dry. Texture is clay, gravelly clay, paragravelly clay, silty clay, paragravelly silty clay or gravelly silty clay with 45 to 60 percent clay. It has 0 to 25 percent gravel and 0 to 10 percent cobbles. Pararock fragments are generally few, but range to 25 percent in the Bt horizon and up to 50 percent below 4 feet in BCt horizon.
The BCt horizon, if present, is clay, silty clay, or gravelly clay with 50 to 60 percent clay. It has color similar to the Bt horizon.
COMPETING SERIES: This is the Edson series and the Orford series in a similar family. Edson soils have channer and flagstone-shaped rock fragments in the particle-size control section. Orford soils have hue of 7.5YR or 10YR and 35 to 45 percent clay in the particle-size control section and are in an isotic mineralogy family class.
GEOGRAPHIC SETTING: Honeygrove soils occur on summits, foot slopes, and toe slopes of mountains. Elevations are 200 to 3,000 feet. Where these soils are mapped in the Oregon Coast Range elevations are typically 200 to 1,800 feet and reach heights of 3,000 feet in the more southern portion of the range in SW Oregon. Where these soils are mapped in the Oregon Cascade Range the typical elevations are 700 to 2,400 feet, and range up to 2,700 feet in the most southern geographic extent of the series in the Cascades. Slopes are 0 to 75 percent. The soils formed in clayey colluvium and residuum derived dominantly from sandstone and siltstone but basalt and tuffaceous rocks are also included. The climate is characterized by warm wet winters and hot moist summers. The mean annual precipitation is dominantly 55 to 90 inches but ranges to 130 inches in the more southern reaches of the Coast Range within Oregon. The mean January temperature is 37 degrees F. and the mean July temperature is 63 degrees F. The mean annual temperature is 45 to 55 degrees F. The frost-free season is 100 to 240 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Apt, Bohannon, Digger, McDuff, Peavine, Preacher, Remote, Shivigny, and Umpcoos soils. All of these soils occur on mountains. Bohannon, Digger, Preacher, Remote and Umpcoos soils have less than 35 percent clay in the particle-size control section and have a solum less than 40 inches thick. Apt and McDuff soils have hues of 10YR or 7.5YR in the particle-size control section. McDuff and Peavine soils are 20 to 40 inches to bedrock. Shivigny soils are clayey-skeletal.
DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability.
USE AND VEGETATION: The soils are used mostly for timber production, recreation, wildlife habitat and watersheds with minor acreage used for pasture, hay, Christmas trees, and small grains. The potential native vegetation is Douglas fir, bigleaf maple, red alder, western hazel, vine maple, Pacific dogwood, western brackenfern, salal, western swordfern, cascade Oregongrape, creambush oceanspray, and baldhip rose. Minor amounts of western hemlock and western redcedar may also be present in some areas.
DISTRIBUTION AND EXTENT: Coast Range and western slopes of the Cascade Range, Oregon; MLRA 1, 3. The series is extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Benton, County, Oregon, 1970. The name is taken from Honeygrove Creek, in the Alsea Valley of western Benton County, Oregon.
REMARKS: Diagnostic horizons and features of this pedon include:
Ochric epipedon - moist chroma of 4 at 6 inches (BAt horizon)
Argillic horizon - from 17 to 75 inches (Bt1, Bt2, Bt3, Bt4 horizons)
Pale feature - percentage of clay does not decrease from its maximum amount by 20 percent or more within a depth of 60 inches from the mineral soil surface
Depths to diagnostic horizons and features are measured from the top of the first mineral layer.
The original series type location for the Honeygrove series was established in the initial soil survey of the Alsea Area, Oregon (published 1973). The modal concept was represented with a clay surface texture. Adjacent survey areas using the Honeygrove series recognized a silty clay loam surface texture as the representative pedon. Over 150,000 acres of the Honeygrove series have been mapped with a silty clay loam surface texture, while only about 12,000 acres were recognized as having a clay surface texture in addition to being located only in the outdated Alsea Area, Oregon survey. With the recent update mapping of Benton County, Oregon Soil Survey, the typical pedon for this soil has been relocated to a more representative site based on further field observations and documentation to reflect a modal concept having a silty clay loam surface texture, mixed mineralogy class, and an active CEC activity class.